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C H E M I S T R Y &

B I O C H E M

Graduate Studies

I S T R Y

GRADUATE STUDIES

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The Georgia Institute of Tech-nology is located in the heartof midtown Atlanta, a modern,vibrant city with a tradition ofcivic pride and diversity.Founded in 1885, the primarygoal of the Institute is to pro-vide superlative education for itsstudents through instruction andresearch. The current enrollmentof approximately 17,000 stu-dents represents every state andmore than 120 countries.The School of Chemistry and

Biochemistry provides an excep-tional environment for graduatetraining. The School has anexcellent balance of establishedsenior faculty and energetic jun-ior faculty with a broad set ofresearch programs. Graduateand undergraduate students,postdoctoral associates, researchscientists, and staff all contri-bute to a dynamic atmospherefor cutting-edge research.With a strong foundation in

traditional areas of physical,organic, inorganic, analytical,polymer, and biological chem-istry, the School has particularstrengths in the chemistry ofnew materials, biomolecularstructure and function,

nanoscience, theoretical chem-istry, and environmental chem-istry. Collaborations with theSchools of Chemical and Bio-molecular Engineering, Earthand Atmospheric Sciences,Biology, Materials Science andEngineering, Civil Engineering,Biomedical Engineering, andPolymer, Textile, and FiberEngineering provide excitinginterdisciplinary opportunities.In addition, researchers use on-campus facilities provided by thecenters for microelectronics,manufacturing, polymers,and biotechnology.

Research is supported at ahigh level by federal agencies(National Science Foundation,National Institutes of Health,Department of Energy, Environ-mental Protection Agency,National Aeronautics and SpaceAdministration), private founda-tions, and industry. In addition,the School plays a major role inthe Center for Fundamental andApplied Evolution (FAME); theCenter for ComputationalMolecular Science and Tech-nology (CCMST), the LaserDynamics Laboratory (LDL), theCenter for Drug Design,

Development and DeliveryFocuses (CD4), the Center forOrganic Photonics and Elec-tronics (COPE), the Institute forBioengineering and Bioscience(IB2), the Signals in the SeaNSF-IGERT initiative, and theMaterials and Devices forInformation TechnologyResearch NSF Science andTechnology Center (STC).

c h e m i s t r y a n d b i o c h e m i s t r y1GT

www.chemistry.gatech.edu

Table of ContentsChemistry and Biochemistry at Georgia Tech . . . . . . . . . . . 1

Research Facilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Graduate Degree Requirements andFinancial Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

Research Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Polymer Chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Physical Chemistry: Single Molecules, Surfaces,Nanoparticles, and Biophysics . . . . . . . . . . . . . . . . . . . . . . 8

Biochemistry, Molecular Biophysics,and Drug Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Inorganic Chemistry: Bioinorganic Chemistryand Inorganic Materials . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Computational and Theoretical Chemistry . . . . . . . . . . 18

Analytical Chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Organic Chemistry: Bioorganic Chemistry and New Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Nanochemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Environmental Chemistry and SustainableTechnologies: Energy, Biorenewable Resources,and “Green” Chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . 28

The Faculty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Atlanta: Showpiece of the South . . . . . . . . . . . . . . . . . . . . . 32

Chemistry and Biochemistry at Georgia Tech

Research FacilitiesSchool of Chemistry and Biochemistry research facilities are con-centrated in the Molecular and Materials Science and EngineeringBuilding (opened in 2006), the Institute for Bioengineering andBiosciences (opened in 1999), the Environmental Science andTechnology Building (opened in 2002), and the Boggs Building.Research laboratories contain a vast array of state-of-the-artinstrumentation including scanning probe microscopes, high-fieldNMR spectrometers (solution, solid state, and imaging), X-ray dif-fractometers (large molecule, small molecule, and powder), anultra-fast laser spectroscopy facility, mass spectrometers (electro-spray, quadrupole, sector MS interfaced to gas and liquid chro-matography, MS/MS and ICP/MS, TOF, and MALDI).

Facilities for biochemistry include equipment for prokaryotic andeukaryotic protein overproduction, protein and DNA sequencing,peptide and DNA synthesis, scintillation counting, ultracentrifuga-tion, and gel and capillary electrophoresis.

For analysis of materials, thermal analysis equipment (TGA, DSC)is located within Boggs, while electron microscopes (SEM, TEM),surface analysis equipment (ESCA), and equipment for mechani-cal analysis (instron, DMA) are readily accessed in adjacent build-ings. In addition, several groups make use of synchrotron X-rayand neutron scattering facilities located at Brookhaven, Argonne,and Oak Ridge National Laboratories. Three-dimensional micro-and nanofabrication equipment includes two dual-beam FIB/SEMinstruments comprising the Focused Ion Beam Service Center.

Other instrumentation within the Boggs Building includes acomplete range of electrochemical equipment and spectrometers(FT-IR, NIR, UV/vis, CD/ORD, MCD, AA, ESR, and fluorimeters).Essentially, any chromatographic purification or characterizationcan be accomplished by techniques such as HPLC, FPLC,GPC, GC, ion chromatography, and centrifugal partition chromatography. In addition to numerous high-end computerworkstations, the School of Chemistry and Biochemistry has a 58-processor Pentium 4/Operton cluster and a 154-processorIntel EM64T cluster networked with a high-speed Infiniband interconnect for parallel computations.

Financial Support for Graduate StudiesThe usual form of financial aid for first-year students is the teaching assist-antship. A vast majority of students beyond the first year are appointed asresearch assistants. The stipends for research assistants are the same as forteaching assistants (2007–2008: $20,250). Teaching and research assis-tants receive full tuition waivers. Additional fellowships are made avail-able with the generous support of individual sponsors and industrial collabo-rators. For example, the President’s Fellowship is a prestigious award thatsupplements the stipend by $5,500 per year for up to four years. Other pro-grams include Cherry Emerson Fellowships, GAANN Fellowships in Chemistryand Biochemistry, GAANN Fellowships in Polymer Science and Engineering,and IGERT Fellowships for the Signals in the Sea program.

Graduate DegreeRequirementsStudents working toward a PhD must complete five graduate-level

classes. Students typically join research groups by the end of the first

semester. In the second year, students present a seminar and com-

plete the PhD candidacy examination consisting of an original

research proposal and preliminary description of progress in the

research laboratory. A series of literature examinations is administered

in the first year to enhance the student’s mastery of the chemical liter-

ature in the major area. The most important requirement for the doc-

toral degree is the ability to carry out independent research as

demonstrated by the completion of published work.

The School of Chemistry and Biochemistry participates in the

Bioinformatics and Paper Science and Engineering multidisciplinary

degree programs, and in the Nanoscience and Technology

certificate program.


Application InformationApplications for graduate admission can be obtained by writing to:

Graduate CoordinatorSchool of Chemistry and BiochemistryGeorgia Institute of TechnologyAtlanta, Georgia 30332-0400

You may request an application by e-mailing [email protected] or via the Web at www.chemistry.gatech.edu.

Applications are accepted throughout the year. Most students begin study in

the fall semester. An application consists of: an information page, official tran-

scripts, and letters of recommendation. Applicants must submit scores for the

GRE general examination. Applications from international students must be

accompanied by a TOEFL score. Most applications are received and consid-

ered between November and February. Competition for fellowships and

stipend supplements is intense, and especially qualified students are encour-

aged to apply early.


Ford Environmental Science and Technology Building

Molecular and Materials Science and Engineering Building (slated to open in 2006)

Polymer Chemistry


Students, faculty, and staff with expertise in traditional disci-

plines all contribute to a highly collaborative and interdiscipli-

nary research program. During the first year of graduate studies,

students complete coursework in one of the traditional areas of

chemistry and biochemistry. However, research projects, while

rooted in traditional chemistry, often involve students in collabo-

rations with an array of other scientists and engineers. As such,

the students’ depth of fundamental chemical principles becomes

augmented by exposure to a breadth of additional concepts.

Such a combination of skills often results in the creation of a

fertile and creative environment for achievement of research

goals. Thus, students frequently expand beyond the reaches of

chemistry subjects and embrace additional areas for the suc-

cessful execution of a specific project.

■ Polymer Chemistry,pages 5-7

■ Physical Chemistry: Single Molecules, Surfaces,Nanoparticles, and Biophysics,pages 8-10

■ Biochemistry, Molecular Biophysics, and Drug Design,pages 12-15

■ Inorganic Chemistry: Bioinorganic Chemistry and Inorganic Materials,pages 16-17

■ Computational and Theoretical Chemistry,pages 18-19

■ Analytical Chemistry,pages 20-21

■ Organic Chemistry: Bioorganic Chemistry and New Materials,pages 22-24

■ Nanochemistry,pages 25-27

■ Environmental Chemistry and Sustainable Technologies: Energy, Biorenewable Resources,and “Green” Chemistry,pages 28-29


ResearchPrograms

Research in polymer chemistry covers a broad set of ini-

tiatives, from the synthesis of new monomers to the

development of new theories for polymerization dynam-

ics. Materials of interest include polymers for microelec-

tronics, packaging, fibers, membranes, and electro-optical

devices. Researchers make use of a large inventory of

shared instrumentation, including facilities for solid-state

nuclear magnetic resonance, thermal analysis, gel perme-

ation chromatography, and X-ray diffraction. The research

is highly collaborative, with close ties to other academic

laboratories and with industrial partners.

Self-assembled CopolymersPROFESSOR M. WECK

Highly functionalized copolymers have important applications, rangingfrom biologically active and electro-optical materials to materials withnovel morphologies or elastomeric properties. Efforts are directed towarddevelopment of new methodologies for the synthesis of copolymers usingself-assembly based on noncovalent interactions. An orthogonal self-assembly approach based on ionic interactions, metal coordination, andhydrogen bonding is used to functionalize “universal” polymeric back-bones that have been synthesized by radical polymerization and ring-opening metathesis polymerization. The syntheses of photorefractive poly-mers, light-emitting diode materials, biologically active polymers, andcross-linked networks are investigated using this methodology.

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Polyphilic Fluoroalkyl Conjugated PolymersPROFESSOR D. COLLARD

Alkyl, perfluoroalkyl, and aromatic segments of molecules often segregatein solid-state structures. Substitution of conjugated polyarylenes (e.g.,polythiophene, polyphenylene) with alkyl and perfluoroalkyl groups pro-vides materials that form highly ordered and oriented solid-state struc-tures and liquid crystalline phases, which can be processed in environ-mentally benign CO2. These materials have a broad range of potentialapplications such as use in sensors, displays, optical communication,and microelectronics.

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Poly(paraphenyleneethynylene)s (PPE) and Related PolymersPROFESSOR U. BUNZ

The synthesis of conjugated polymers is an important field in organicmaterials. New synthetic approaches to PPE have been developed thatfurnish these polymers in quantitative yields and with a high degree ofpolymerization. Almost all aromatic diiodides can be transformed intoPPE-type materials if acetylene gas is used as a reagent in the presenceof a very small amount of a Pd-catalyst. The polymers are used in semi-conductor devices and for spectroscopic studies.


Polymers for Microelectronics and PhotovoltaicsPROFESSOR L . TOLBERT

The increasing demand by the electronics industry for high-temperature,low-dielectric, stable thin films places increasing demands on polymer sci-ence for the development of new materials and new processing methods.Diamond-like films and high-carbon polymers are being synthesized, withparticular attention to uses in nanolithography, to develop low-cost, sol-ventless processing methods to prepare ultra-high resolution films andmasks. Conducting polymers are being investigated for makingorganic/inorganic hybrid photovoltaic cells.

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NMR Studies of Fluids in Porous MediaPROFESSOR H. BECKHAM

Uptake and loss of fluids are among the most important functions ofporous substrates, impacting both their manufacture as well as end-useapplications. Nuclear magnetic resonance (NMR) is the basis of a particu-larly powerful suite of techniques with which to examine water (and otherfluids) inside anisotropic porous media. A variety of NMR methods (imag-ing, diffusion, spectroscopy) are being used to extract a deeper under-standing of the interactions of water with porous substrates.

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Biogenic and Bioresponsive Conjugated PolymersPROFESSOR U. BUNZ

Sensing of pathogens and biological toxins such as anthrax and ricin hastaken on an increased urgency. These types of toxins bind strongly to mul-tivalent biological sugar displays. These biological sugar displays can bemimicked in conjunction with sugar-substituted conjugated polymers.These “bio-PPEs” show a change of emission when exposed to toxinmodels. The goal of this project is to optimize binding of PPEs to sugar-binding proteins and develop a dipstick test for ricin and related toxins.

Threaded and Cyclic MacromoleculesPROFESSOR H. BECKHAM

Rotaxanated polymers consist of cyclic molecules threaded onto linearpolymer segments. These topological copolymers combine the characteris-tics of the two components in ways that yield bulk properties that are dif-ferent from analogous block or graft copolymers. The molecular dynamics,phase structures, and bulk properties of these materials are being exam-ined using a variety of physical techniques.

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Polymer Bonding Materials for Low-cost Chip PackagingPROFESSOR C. P. WONG

Novel reworkable, fast-curing, high-performance materials are beingdeveloped to reduce processing time and material costs to make comp-uter chip packages for wireless, global positioning, PCs, and informationappliances. Current epoxy-based materials take so long to process thatthey become a bottleneck for high-volume production. The new materialsare novel polymers that do not exhibit the drawbacks of conventionalmaterials, such as high viscosity, long cure time, short shelf life, and sus-ceptibility to moisture. Furthermore, syntheses and processes of ultra-high-k and high Q nanocomposites for embedded capacitors and induc-tors, and self-assembled monolayer nanomaterials for high-currentdensity, electrically conductive adhesives are under investigation.

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Bubble Array Formation of Conjugated PolymersPROFESSORS M. SRINIVASARAO AND U. BUNZ

Development of dynamic methods to template organic materials is impor-tant to access microstructures that are useful as photonic bandgap mate-rials, self-cleaning surfaces, and self-colored materials. The breath figuremethod provides rapid access to such microstructures: warm, moist air isblown over a dilute solution of a polymer in a volatile solvent and, as thesolvent cools due to evaporation, water droplets condense onto the sur-face of the solvent. These droplets organize and form a highly ordered,hexagonally ordered array. Once all of the droplets have evaporated, a“fossil” of the water droplets is preserved in the polymer as a hexa-gonally ordered bubble array.

Fundamentals of Colloidal AssemblyPROFESSOR L . A. LYON

The use of colloidal particles and assemblies is ubiquitous amongst suchindustries as food, cosmetics, and paint, and has far reaching potentialin such areas as optics, electronics, and the development of medicaldevices. This research project focuses on the fundamental behaviors ofsoft microgel particles as they assemble to form colloidal crystals andglasses. New colloidal phases are being designed and investigated bytuning both the repulsive and attractive portions of the particle interac-tion potentials, both in terms of the mechanics (softness) and chemicalmoieties (Coulombic repulsion, hydrogen bonding).

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Oligopeptides as Building Blocks in Molecular TectonicsPROFESSOR M. WECK

Nanoporous materials containing interconnected microscopic cavities areof outstanding importance in industry and everyday life. Applicationsrange from filtration, extraction, and drug delivery systems to membraneseparators. The development of a new methodology to use peptide struc-tures in metal coordination/hydrogen bonding-based self-assembly toyield biomaterials and superlattices is a major area of interest. Coord-ination of palladium-functionalized compounds to pyridine-functionalizedamino acid residues facilitates the self-assembly of peptide chains intosuperstructures, such as transmembrane pores.

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New Surfaces and Functionalized Poly(lactide)s for Tissue EngineeringPROFESSORS D. COLLARD AND M. WECK

Advances in tissue engineering rely on cells retaining their function whenadsorbed on non-natural substrates. New polymer films are being devel-oped that resist nonspecific adhesion, while promoting assembly offibronectin so as to mimic natural extracellular matrices. Biorenewablepolymers such as poly(lactic acid) are promising precursors for futurematerials but a lack of chemical diversity of currently available polymerslimits their potential applications. The aim of this initiative is to developnovel synthetic strategies toward functionalized polylactides to overcomethese limitations.

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Molecularly Imprinted Polymers (MIPs)PROFESSOR B. MIZAIKOFF

Molecularly imprinted polymers (MIPs) are synthesized in such a way thata target analyte serves as a template for a copolymerization process tocreate synthetic receptor sites within a scaffolding material. Biologicallyinspired (biomimetic) recognition is widely engineered into syntheticmaterials by mimicking motifs found in nature. The synthesis of receptorsites capable of selective binding with comparable efficiency to substrate-enzyme or antibody-antigen interactions is a main goal of molecularimprinting. Current research orchestrates a range of analytical methods(NMR, FT-IR, ITC, BET, HPLC, SPE) to characterize the polymerizationprocesses and binding properties to provide the fundamental analyticalbasis for the rational design of new selective MIPs.

See also:

> Organic Electronics, page 24, Professors S. Marder, M. Weck, L. Tolbert, U. Bunz,and D. Collard

> Electronic Structure of Organic Semiconductors and Their Interfaces, page 18,Professors J.-L. Brédas, S. Marder, J. Perry, L. Tolbert, and M. Weck

> Dynamics of Electronic Processes in π−Conjugated Materials, page 19,Professor J.-L. Brédas

> Two-photon Chemistry, page 23, Professor S. Marder

> Nano-biocomposites, page 26, Professor A. Ragauskas

> Photoacids, Photobiology, and Photopolymerization, page 23, Professor L. Tolbert

> Immobilized Single-site Organometallic Catalysts, page 17, Professor C. Jones

> Bioanalysis with Bioresponsive Materials, page 20, Professor L. A. Lyon

> Designed Bio-interfaces, page 26, Professors L. A. Lyon, M. Weck, and A. Garcia




The experimental physical chemistry program at Georgia

Tech has particular strengths in nanostructures, surface

and interfacial science, and biophysical chemistry.

Facilities include those for single molecule spectroscopy,

imaging, molecular and electron beam techniques, and

the Laser Dynamics Lab, which houses state-of-the-art

lasers and other time-resolved equipment. In addition,

there are strong collaborations with groups interested in

computational and theoretical physical chemistry

(see pages 17–18).

Fluorescence Imaging of Cellular Reaction DynamicsPROFESSOR C. PAYNE

Fluorescence microscopy reveals the subcellular location, concentration,and reaction rate of a range of chemical reactions that occur withincells. Reactions of interest are associated with the targeting, delivery,and catalysis of proteins for degradation. These systems pose a numberof physical and biological questions, including the mechanism of intracel-lular transport, kinetics of vesicle fusion, influence of the local environ-ment on a chemical reaction, and conversion of chemical energy intomechanical motion.

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Shape-dependent NanocatalysisPROFESSORS M. EL-SAYED AND Z. L . WANG

Transition metal nanoparticles are synthesized with different sizes andshapes (e.g. cubic, tetrahedral, truncated octahedral). Surface metalatoms of different particle shapes have different electronic structures andthus different catalytic properties. Studies focus on the catalytic propertiesof particles of different shapes for gaseous reactions and importantorganic reactions in aqueous solutions.

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Synthesis and Characterization of Nanocrystals and ArraysPROFESSOR R. WHETTEN

The motivation of research into nanocrystals stems from the need tounderstand both the natural phenomena involved and technologicalquestions concerning the ultimate limits on the miniaturization of solid-state devices. Research spans from synthesis to supercomputer-basedsimulations. Characterization is done by high-resolution electronmicroscopy; small- and large-angle X-ray powder diffraction; scanningprobe microscopy; X-ray photoelectron spectroscopy; optical and infraredspectroscopy; laser desorption; and matrix-assisted laser desorption ion-ization time-of-flight mass spectrometry.

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Single-molecule Orientational MicroscopyPROFESSOR R. DICKSON

The world’s only methods for determining true 3-D single-molecule orien-tations have been developed at Georgia Tech. Since each molecule inter-acts differently with its surroundings, great diversity is observed in molec-ular behaviors. For example, single molecules in polymeric matricesexhibit surprising rotational mobilities that are indicative of nanoscalepolymer dynamics. Such molecular orientational studies directly probebiological and materials systems to provide understandings oftheir dynamics.

Physical Chemistry:Single Molecules,Surfaces,Nanoparticles,and Biophysics

Nonlinear Optical Properties of Organic Photonic MaterialsPROFESSOR J. PERRY

Conjugated organic materials are of great interest in photonics as non-linear media for efficient optically switchable or tunable devices. Non-linear spectroscopic studies, including two-photon absorption, opticalpower limiting, nonlinear frequency conversion, and degenerate four-wave mixing experiments, are performed on conjugated organic mole-cules, oligomers, and polymers as part of an integrated program todevelop an understanding of the relationships between molecular struc-ture and optical properties. To this end, femtosecond laser-based nonlin-ear optical methods are utilized to examine the roles of the symmetryand degree of intramolecular charge transfer, electronic delocalization,and extended conjugation length in the strength and spectral depend-ence of the nonlinearities.

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Electron Transfer in EnzymesPROFESSOR B. BARRY

Long-distance electron transfer in proteins involves step-wise reactionsbetween pairs of redox-active prosthetic groups, which act as catalyticintermediates. These prosthetic groups include covalently and noncova-lently bound cofactors, such as heme, pheophytin, and chl, as well asamino acid side chains. An important long-term goal of this researchproject is to determine how electron transfer rates are influenced bychanges in the structure and environment of these redox intermediates.Electron transfer mechanisms that involve redox-active amino acids inenzymes and in model peptides are investigated using EPR and time-resolved vibrational spectroscopy and, in collaborative efforts, electronspin-echo envelope modulation (ESEEM) and density functional (DFT) cal-culations. In addition, electron transfer mechanisms that involve tetrapyr-role-derived cofactors are being investigated to elucidate the factorsresponsible for midpoint potential control in oxido-reductases.

Cold Molecular IonsPROFESSOR K. BROWN

The reaction dynamics of molecules at millikelvin temperatures exhibitinteresting quantum mechanical effects that are typically hidden by ther-mal averaging. To achieve these temperatures, molecular ions are cooledand analyzed by laser-induced interactions with ions in a multi-zone iontrap. This technique allows for the detection of weak molecular transi-tions by atomic fluorescence, which will be useful for fundamental stud-ies of chemical reactions.

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Femtosecond Dynamics of Semiconductor NanoparticlesPROFESSOR M. EL-SAYED

The properties of matter are determined by a characteristic length avail-able for electrons to undergo motion. If the dimensions of the materialare reduced to below this length, which is usually on the nanometerscale, its properties change and become sensitive to its size and shape.This fact makes nanoscale materials potentially important for future tech-nologies. The properties of these materials, such as semiconductor nano-particles, are studied by measurement of the femtosecond dynamics ofthe electrons and holes, surface trapping, and other relaxation processesas a function of size and shape.


Low-energy Electron Collisions with Complex TargetsPROFESSOR T. ORLANDO

There is great interest in scattering of low-energy (1-100ev) electrons bymolecular solids, surfaces, and interfaces. Quantum-resolved studies are performed on the dissociative electron attachment resonances on/in con-densed molecular solids and stimulated adsorption/dissociation of adsor-bates. The project concentrates on the question of how gas-phase conceptshave to be modified when trying to understand electron collisions with com-plex targets. Work is also under way to produce nano-structures by quan-tum-interference phenomena during low-energy electron scattering.

Oxide Surface ChemistryPROFESSOR T. ORLANDO

Analysis of interfacial metal-oxide reactions using ultra-high vacuum systemsequipped to carry out high-temperature electrochemical reactions allows forcharacterization of electrochemical processes involved in fuel cells and thenonthermal interfacial energy transfer processes leading to the production ofmolecular hydrogen. Reactions of hydrogen, water, and oxygen on metal-oxide surfaces (amorphous, crystalline, and polycrystalline samples) are stud-ied using chemically specific nanoscale imaging techniques based on non-thermal electron-stimulated desorption (ESD). The approach uses sensitivelaser detection schemes based on multi-photon ionization of the neutraldesorption products and can be used to examine the electronic and geomet-ric structures associated with surface defects and grain boundaries.

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Mechanisms of Solar-to-Electric Energy Conversion in NaturePROFESSOR M. EL-SAYED

There are two photosynthetic systems in nature: the chlorophyll-based sys-tem and a retinal-based system called bacteriorhodopsin (bR) present inHalobacterium Salinarium. The first is an electron pump, while bR is a solarproton pump. Upon light absorption, bR undergoes a photocycle and pumpsprotons from the cell interior to its membrane surface. Techniques such asultrafast time-resolved optical, Raman, and FTIR spectroscopy are used tounderstand the following: the mechanism and the role of the protein in theretinal photoisomerization; the role of metal cations in the proton pumpfunction; the molecular mechanism of the protons transport from the interiorto the surface of the bR cell; and the molecular mechanism(s) of the proteinmelting in this unusually thermally stable system.

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New Technologies for Live Cell ImagingPROFESSOR C. PAYNE

Fluorescence microscopy of living cells is limited by competition betweenemission from fluorescent probes and autofluorescence of the cell. Thedevelopment of optical techniques and probe delivery methods is needed toenable more quantitative cellular imaging. Optical methods include nanome-ter-level imaging, spectroscopic single-particle tracking, multiphoton totalinternal reflection, and zero-order waveguide imaging. New delivery meth-ods will introduce fluorescent probes into cells in a controlled manner.

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Two-photon 3-D Fluorescence Imaging of BiomolecularInteractionsPROFESSOR J. PERRY

Two-photon laser scanning fluorescence microscopy provides a means forreal-time imaging of cellular processes and the monitoring of biomolecularinteractions. Efficient two-photon excitable fluorescent probes are studiedfor ultrasensitive detection, sensing, and imaging in collaboration with theMarder and Fahrni groups. The enhancement of two-photon absorption byintermolecular interactions, coupling of dyes and metal nanoparticles, andthe effects of local field and environmental effects are examined. In collabo-ration with Victor Hruby’s group at the University of Arizona, real-time two-photon imaging is used to monitor the rates of peptide drug uptake bytransfected cell lines expressing human G-protein coupled receptors to rap-idly characterize the biological activity of the drug.

Nonthermal Processes at Biological Interfaces andDevelopment of Laser-based Mass Spectrometry TechniquesPROFESSOR T. ORLANDO

The inelastic scattering of low-energy electrons leads to DNA damage byformation and decay of localized scattering resonances. Thus, low-energy,electron-initiated damage of DNA is under investigation, both theoreticallyand experimentally. The theoretical approach uses scattering theory, whilethe experimental approach uses low-energy electron scattering and ultra-high vacuum systems equipped with novel liquid dosers and vacuum ultravi-olet (VUV) lasers. This experimental approach is also used to investigate themechanisms of surface-enhanced laser desorption/ionization mass spectrom-etry (SELDI MS) and to develop novel analytical techniques for metabolitemapping in biological samples.

See also:

> Planetary and Environmental Surface Science, page 29, Professor T. Orlando

> Magnetic Nanoparticles, page 17, Professor Z. J. Zhang

> Optical Properties of Individual Nanoparticles, page 25, R. Dickson

> Nanopatterning and Enhanced Film Growth Using Low-Energy Electrons,page 25, Professor T. Orlando

> Multi-photon 3-D Micro- and Nano-fabrication, page 25, Professor J. Perry

> New Properties of Noble Metal Nanoparticles, page 25, Professor M. El-Sayed

> Bubble Array Formation of Conjugated Polymers, page 6,Professors M. Srinivasarao and U. Bunz

> Post-translational Modifications in Membrane Proteins, page 12,Professor B. Barry

> Oxygen Production in Plant Photosynthesis, page 14, Professor B. Barry

> Quantum Simulations of Molecules and Materials, page 18, Professor K. Brown

> Atmospheric Chemical Kinetics and Photochemistry, page 28, Professor P. Wine

> Fundamentals of Colloidal Assembly, page 7, Professor L. A. Lyon



Structural Elucidation of Nucleic Acid and Protease ComplexesPROFESSOR L . WILLIAMS

The 3-D structures of nucleic acids are modulated and deformed bysequence, covalent damage, and the presence of proteins, other nucleicacids, intercalators, groove binders, and ions. Structural elucidation byX-ray crystallography provides detailed structural information. A seriesof bis-intercalators (ditercalinium, flexi-di, WP631, and D232) andmono-intercalators (photo-cleaver) bound to DNA fragments are studied.Other research focuses on understanding the structure of serine proteaseenzymes and enzyme-inhibitor complexes. Structural analysis of protease-inhibitor complexes provides critical information on the mechanisms ofscission and inhibition, and for design of new inhibitors.

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Engineering Nuclear Hormone ReceptorsPROFESSOR D. DOYLE

Nuclear hormone receptors control the expression of genes in response tosmall molecule hormones. In performing this activity, the receptors mustspecifically recognize small molecules, DNA, and other proteins. Theamino acids that recognize each of these substrates are varied, usinggenetic engineering techniques, until a receptor with novel recognition iscreated. The original and new receptors are studied using a variety of bio-physical techniques to elucidate the principles behind the new activity.This exercise provides both new knowledge for future protein engineeringand real materials for research and medical applications.

Protease InhibitorsPROFESSOR J. POWERS

Mechanism-based (or suicide) and transition-state inhibitors are designedand synthesized for proteolytic (protein degrading) enzymes of therapeuticimportance. Proteolytic enzymes under investigation include serine pro-teases that function in the killing of virally infected and tumor cells bynatural killer cells and cytotoxic T lymphocytes. Inhibitors for calpain, acysteine protease involved in neurodegeneration, have potential therapeu-tic utility for the treatment of stroke, Alzheimer’s disease, and peripheralneuropathy, and inhibitors for caspases and related cysteine proteaseshave potential for the treatment of Huntington’s disease, Parkinson’s dis-ease, amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS), spinalmuscular atrophy, inflammation, and cancer.

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Neuropeptide Processing and Molecular NeurochemistryPROFESSOR S. MAY

Research focuses on rational, molecular-based approaches to problemsin neurochemistry, with particular emphasis on the post-translationalprocessing of biologically active peptides. Novel compounds capable ofacting as suicide substrates and transition-state analogs toward specifictarget enzymes are designed and synthesized, and used in enzymologicalinvestigations, in cellular-level studies in the tissue-culture laboratory,and in pharmacological experiments. Coupled with this work, bothchemical and physical techniques are used to investigate the structure,reactivity, and detailed stereochemistry of enzymes involved in the bio-synthesis and metabolism of neuropeptides, peptide hormones, andother neurotransmitters.

An understanding of the structure of biological macro-

molecules (DNA, RNA, proteins, carbohydrates) is impor-

tant in determining their function and in the design of

new medicinal agents. Research focuses on structural

analysis of nucleic acids, protease-inhibitor complexes,

high-resolution fluorescent probe technologies, recombi-

nant DNA techniques, X-ray diffraction, nuclear magnetic

resonance, and scanning probe microscopy. These tools,

together with organic synthesis, enzymology, and funda-

mental studies in bioorganic and bioinorganic chemistry,

are applied to the development of new pharmaceuticals

for the treatment of cancer, AIDS, heart disease,

Alzheimer’s disease, hypertension, and drug abuse.

Understanding and Controlling Nucleic Acid AssemblyPROFESSOR N. HUD

Elucidation of the chemical and physical principles that govern nucleicacid assembly and the development of novel ways to control this assem-bly in vitro are vital to provide an understanding of the structure andfunction of DNA and RNA. A variety of biophysical and biochemical tech-niques are employed, including electron microscopy (TEM), nuclear mag-netic resonance (NMR), circular dichroism (CD), dynamic light scattering(DLS), and recombinant DNA technology. Research projects include thedevelopment of new methods for controlling DNA condensation for theimprovement of artificial gene delivery, development of an artificial self-replicating system capable of evolution, and investigations into the originof life and the RNA world.

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Post-translational Modifications in Membrane ProteinsPROFESSOR B. BARRY

Amino acid side chains in proteins can be modified during or after thesynthesis of the protein. The modified amino acid may have unique reac-tivity or may provide a cellular signal. There is little known about suchmodifications in photosynthetic enzymes. Mass spectrometry and peptidemapping are used to identify interesting, modified amino acids in a pho-tosynthetic membrane protein, photosystem II. A subset of these modi-fied amino acids is located at the active site for water oxidation and mayplay a role in the structure and function of the enzyme. Other photosys-tem II modifications may be important in signaling for the turnover ordegradation of the enzyme inside the cell.

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Oligonucleotide-Small Molecule InteractionsPROFESSOR A. OYELERE

Despite the chemical similarities between RNA and DNA, and their directrole in gene expression, little is known about the extent to which RNAserves as targets for oligonucleotide reactive agents. The primary goal ofthis study is to elucidate a set of rules that govern the reactivity of RNAtoward nucleic acid-modifying agents to provide new insights into thebiological consequences of these modifications.

Biochemistry,MolecularBiophysics,and DrugDesign



Biosynthetic EngineeringPROFESSOR W. KELLY

Resistance to antibacterial chemotherapies demands constant discoveryand development of new therapeutic agents. A substantial fraction ofantimicrobial natural products are biosynthesized by either non-ribosomalpeptide synthetases or polyketide synthases, which are multi-modular andoften multi-enzyme complexes. Evidence continues to mount supportingthat these enzyme classes are amenable to biosynthetic engineering in aneffort to generate designer metabolites, and the application of thisapproach to generate novel antibacterial agents is being examined.

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Biomineralization PROFESSORS N. KRÖGER AND N. POULSEN

Unicellular microalgae such as diatoms, radiolaria, and cocolithophoreshave the remarkable ability to produce nanopatterned inorganic structuresmade of SiO2 or CaCO3 (biominerals). This remarkable control over forma-tion and 3-D assembly of a mineral under ambient conditions by farexceeds the capabilities of human technology. State-of-the-art biochemi-cal and molecular genetic techniques are employed to identify themolecular and cellular machineries of these fascinating biomineral-ization processes.

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Protein Folding and Ligand BindingPROFESSOR R. HERNANDEZ

Minimalist lattice and off-lattice models provide insight into the foldingbehavior of proteins without suffering high computational costs. MonteCarlo simulations of designed minimalist proteins are studied to providean understanding of the connection between protein structure anddynamics. This, in turn, is being used to analyze the behavior of all-atomdynamics in small peptides. In addition, computational techniques usefulfor analyzing and predicting a binding partner to a particular agent arebeing developed.

See also:

> Bioorganic Chemistry of Polyketide and Nonribosomal PeptideAntibiotics, page 22, Professor W. Kelly

> Fluorescence Imaging of Cellular Reaction Dynamics, page 8,Professor C. Payne

> Nonthermal Processes at Biological Interfaces and Development of Laser-based Mass Spectrometry Techniques,page 10, Professor T. Orlando

> Fundamental Forces of Molecular Recognition, page 19,Professor C. D. Sherrill

> Bio-organometallic Catalysts, page 22, Professor C. Fahrni

> Chemical Ecology and Chemical Communication, page 23,Professor J. Kubanek

> DNA–Photochemistry and Charge Transport, page 23,Professor G. Schuster

> Novel Synthesis of Biofuels and Biochemicals, page 29,Professor A. Ragauskas

> Biogenic and Bioresponsive Conjugated Polymers, page 6,Professor U. Bunz

> Nano-biocomposites, page 26, Professor A. Ragauskas

> Mass Spectrometry and Proteomics, page 20,Professor F. Fernandez

> Nanomechanics of Nucleic Acids and Proteins, page 27,Professor L. Bottomley

> Fluorescence Probes for Intracellular Storage, Trafficking, and Homeostasis of Trace Elements, page 16, Professor C. Fahrni

> Multifunctional Scanning Nanoprobes, page 26,Professors B. Mizaikoff and C. Kranz

> Bio-enabled Syntheses of Functional Inorganic Materials,page 17, Professor N. Kröger

> Biotechnological Approaches for Production of New Materials,page 29, Professor S. May

> Biocatalysis, page 29, Professor A. Bommarius

> Electron Transfer in Enzymes, page 9, Professor B. Barry

> Design of Novel DNA-intercalating Topoisomerase Inhibitors as Antitumor and Anti-infective Agents, page 22,Professor A. Oyelere

Computational Structural BiologyPROFESSOR S. HARVEY

A variety of computer modeling methods, including molecular graphicsand molecular mechanics (molecular dynamics, Monte Carlo, etc.), areused to investigate structure-function relationships in biological macro-molecules. Systems of interest range from individual biological macromol-ecules up to very large assemblies. Specifically, major efforts are made onhigh-density lipoproteins, the packaging of RNA and DNA viral genomes,the ribosome and its interactions with tRNAs and various cofactors, andalgorithm development. Most of this work involves close collaborationwith experimentalists, and students supplement their theoretical and com-putational work by doing experiments in collaborators’ laboratories.

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Oxygen Production in Plant PhotosynthesisPROFESSOR B. BARRY

Oxygenic photosynthesis is essential in the maintenance of life on earth.This type of photosynthesis requires the concerted action of two reactioncenters that convert light energy into a transmembrane charge separa-tion. One of these reaction centers, photosystem II (PS II), catalyzes theoxidation of water and the production of molecular oxygen. PS II consistsboth of integral membrane-spanning subunits and extrinsic subunits. Theextrinsic subunit manganese-stabilizing protein (MSP) prevents loss ofmanganese from the active site and is required for optimal rates of oxy-gen evolution. Vibrational spectroscopy is used to obtain detailed infor-mation about structural changes occurring during oxygen production.

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Molecular Basis of Selenium’s Role in Human Healthand DiseasePROFESSOR S. MAY

The biochemistry and pharmacology of selenium are subjects of intenseinterest because of strong evidence that a deficiency of this trace nutrientplays a key role in diseases as diverse as cancer, heart disease, arthritis,and AIDS. Structure-level information is obtained regarding the selenium-containing metabolites formed in normal and diseased human fluids andtissues. Advanced separation and mass spectral techniques are utilized in

collaboration with the U.S. Centers for Disease Control and Preventionand several medical schools. In addition, novel selenium-based anti-hyper-tensive agents have been developed that protect DNA against damagecaused by oxidants generated during cellular metabolism. Both aspects ofthis project provide significant new information regarding the biochemicallink between selenium metabolism and human health and disease.

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Organized Nucleic AcidsPROFESSOR N. HUD

RNA and DNA form a number of fascinating higher order structures. NMRspectroscopy is used to determine the structure of nucleic acid moleculesand assemblies, along with their cation-binding sites in the solution state.Electron microscopy is used to study the condensation of DNA into nano-meter-scale particles.

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The Role of ATP in Cystic FibrosisPROFESSORS B. MIZAIKOFF AND C. KRANZ

Abnormalities in ATP release are expected to play a major role in thepathophysiology of cystic fibrosis (CF), a polyexocrinopathy characterizedby altered secretion of chloride by airway epithelia, pancreas, intestine,and sweat ducts. The activation of the CF transmembrane conductanceregulator is associated with the release of ATP into the extracellular envi-ronment. A fundamental goal of research in this area is the laterallyresolved detection of transmitter molecules at cellular surfaces with hightemporal and spatial resolution using bifunctional scanning probes. Thisconcept is based on microfabricating an electroactive area into AFM tips,and is expanding to the integration of amperometric nanobiosensors intoAFM probes, with the aim of quantitatively imaging ATP release events ata single cell level.



Magnetic NanoparticlesPROFESSOR Z. J. ZHANG

Research focuses on the synthesis and characterization of nanoparticles ofmagnetic metal oxides such as ferrites, with an emphasis on chemicalcontrol of magnetic properties. The goal is to understand the novel prop-erties of magnetic nanoparticles at the atomic level, and toward this end,an interdisciplinary approach has been developed that combines chemicalsynthesis, transmission electron microscopy, X-ray and neutron diffraction,Mössbauer spectroscopy, and magneto-optical measurements to systemat-ically elucidate the relationships between magnetic properties and chemi-cal composition/structure.

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Synthetic and Mechanistic Inorganic ChemistryPROFESSOR E. K. BAREFIELD

Attempts to elucidate the chemical mechanisms of gas generation (H2,N2O, N2, NH3) in nuclear waste storage tanks have led to the realizationthat much is still unknown about the solution chemistry of nitrogenoxyanions, especially in highly basic media. These gases result from nitriteion oxidation of metal chelating agents present in the waste. Aluminum(III), which is also a waste constituent, catalyzes gas production mostlikely through the formation of an aluminum nitrite species, and inferentialevidence suggests that NO is generated as an intermediate. Attempts aremade to prepare examples of aluminum nitrite for studies of their react-ivity. Although NO is well characterized in the gas phase, very little isknown about its behavior in solution. Efforts are under way to synthesizeprecursors to NO that will allow the study of its chemical behavior undercontrolled conditions.

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Immobilized Single-Site Organometallic CatalystsPROFESSOR C. JONES

New approaches are being developed for the design of single-site metalcomplex catalysts on silica surfaces. A variety of transition metal complexcatalysts (Ti-, Zr-, Hf-, Fe-, Ru-, Pd-, Cu-, Co-, or Zn-based) have beenimmobilized on silica and polymer supports and utilized for the synthesisof polymers, chiral pharmaceutical intermediates, and other organic prod-ucts. This research sits at the interface of chemistry and chemical engi-neering and involves synthetic organic and organometallic chemistry,materials characterization, and catalysis.

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Application of Synchrotron X-ray MethodsPROFESSOR A. WILKINSON

The extremely high intensity and high-energy X-ray beams that are avail-able from synchrotrons provide unique opportunities for examining mate-rials. They can be used to penetrate bulk samples and sample cells, andthey are so intense that reactions can be followed in real time. Methodsfor the in-situ, real-time examination of cement hydration under oil wellconditions (up to 1000 bar and 250 ºC) are being developed and used incollaboration with an industrial partner.

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Design and Synthesis of Transition Metal Catalyst SupportsPROFESSORS M. WECK, C. JONES, AND C. D. SHERRILL

A large number of materials ranging from polymers to nanoparticles andnanoporous silica are being evaluated as supports for transition metalcomplex catalysts in this joint experimental/theoretical project. In particu-lar, catalysts for carbon-carbon bond formations and epoxidations are

evaluated due to their importance in small-molecule catalysis and thepharmaceutical industry. By comparing the catalytic activity and selectivityof a specific catalyst on different supports, a detailed understanding of themetal complex/support interface can be obtained and structure/functionrelationships between supports and catalysts can be developed.

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ThermoelectricsPROFESSOR A. WILKINSON

There is considerable interest in developing new materials that mightallow the replacement of refrigeration technology with efficient all-solid-state devices. Thermoelectric devices can be used to provide power from atemperature difference or to produce a temperature difference when sup-plied with electrical power. Clathrate semiconductors with 3-D frameworksof Si, Ge, or Sn and species such as Cs, Rb, K, Na, Sr, or Eu rattling insidecavities in the framework are attractive thermoelectric materials. The disor-der associated with the rattling has a big impact on their properties. Theoccurrence and importance of disorder in clathrate thermoelectric materi-als are examined in collaboration with researchers at Argonne NationalLaboratory and the University of Southern Florida.

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Bio-enabled Syntheses of Functional Inorganic MaterialsPROFESSOR N. KRÖGER

Direct syntheses of functional organic-inorganic hybrid materials are oftenrestricted by incompatible conditions required to form the desired organicand ceramic phases. Novel methods are being developed based on themechanisms of biological mineral formation (biomineralization) to solvethis problem. Projects include the design of recombinant proteins with invitro mineral-forming activities, and the genetic engineering of diatomsthat produce functional SiO2-based structures.

See also:

> Bio-organometallic Catalysts, page 22, Professor C. Fahrni

> Photoinduced Multielectron Chemistry for Solar Fuels Production, page 29,Professor J. Soper

> Biomineralization, page 15, Professors N. Kröger and N. Poulsen

Research programs in inorganic chemistry include

dynamic efforts in the preparation and examination of

new materials, development of analytical methods for

the characterization of materials, bioinorganic chemistry,

and mechanistic inorganic chemistry. Facilities include

well-equipped synthetic laboratories, high-field solution

and solid-state NMR capabilities, Mössbauer and ESR

spectrometers, a SQUID magnetometer, and modern

X-ray fluorescence and diffraction equipment, electron

microscopes, and microfabrication facilities. In addition,

neutron and synchrotron X-ray instrumentation is used

extensively at several national laboratories.

Bioinspired Designs for Small-molecule ActivationPROFESSOR J. SOPER

Biological multielectron chemistry provides the inspiration for develop-ment of new classes of multielectron reactions by coupling redox activityat first-row metal ions to redox transformations at “non-innocent”charge-localized ligands. Non-innocent transition metal complexes thatcan store multiple redox equivalents in ligand-based electron reservoirsare being developed for small-molecule functionalization, including:1) novel electrophilic C-H activation and biomimetic O2 reduction;and 2) controlled radical processes for low-barrier X-H bond-makingand bond-breaking.

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New Materials with Negative Thermal ExpansionPROFESSOR A. WILKINSON

Controlling thermal expansion is important. For example, 1) the bondingof materials with widely differing thermal expansion coefficients leads tointerfacial stresses on heating or cooling; and 2) rapid temperaturechanges can lead to the failure of materials with large thermal expansioncoefficients. Although most materials expand when heated (positiveexpansion), there are some that display zero or negative thermal expan-sion. Compounds displaying negative thermal expansion are preparedusing low-temperature methods, and their properties examined.

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Fluorescence Probes for Intracellular Storage, Trafficking,and Homeostasis of Trace ElementsPROFESSOR C. FAHRNI

Metal-specific fluorescent sensors are important tools in probing the roleof transition metals in cellular biology. Research includes the develop-ment of zinc-selective fluorescent sensors for two-photon excitationmicroscopy (TPEM) to study the dynamics of labile zinc pools in cell cul-tures and tissues. Furthermore, fluorescence probes are developed for thedetailed mechanistic investigation of copper storage and trafficking. Theintracellular topography of labile metal pools is explored using thesecation-selective sensors in combination with immunofluorescence tech-niques. The underlying homeostatic mechanisms are studied by confocaland multiphoton fluorescence microscopy as well as by synchrotron X-rayfluorescence microscopy (at the Argonne National Laboratory).

InorganicChemistry:BioinorganicChemistryand InorganicMaterials


Far-From-Equilibrium Chemistry:Swelling and Driven ColloidsPROFESSOR R. HERNANDEZ

Despite the many successes of statistical mechanics in describing equilibri-um and near-equilibrium behavior, truly non-equilibrium chemical dynam-ics remain poorly characterized by theory or computation. For example,suspensions of driven colloids–with a shape that changes in size or orien-tation–lead to macroscopic materials with emergent properties and com-plex solubility. Such systems are not presently well understood becausethey involve several disparate time and length scales, but are increasinglybeing explored experimentally using optical microscopy on various nano-particle suspensions. These systems are studied using both moleculardynamics simulations and reduced-dimensional representations.

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Nonlinear Optical Properties of π-ConjugatedChromophoresPROFESSORS J. -L . BRÉDAS, S. MARDER, J. PERRY,AND C. FAHRNI

The ease with which π-electrons can delocalize upon application ofan electromagnetic field makes conjugated chromophores ideally suitedfor nonlinear optical (NLO) applications and their incorporation intophotonic or electro-optic devices. Computational methods are used toestablish structure-NLO property relationships and to design chromo-phores with enhanced second-order and/or third-order response. Majorefforts are currently devoted to the development of chromophores withhigh two-photon absorption cross sections (that is, with the ability ofabsorbing two photons simultaneously). The theoretical investigationsinvolve new conjugated systems with applications in all-optical signalprocessing, 3-D nanofabrication, data storage, or metal biosensing incellular environments.

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Far-From-Equilibrium Chemistry:Controlling Diffusion on SurfacesPROFESSOR R. HERNANDEZ

Can one control the motion of metal atoms “surfing” on a metallic surfaceand then anchor them at desired locations? Yes. An STM tip can literally beused to move atoms one at a time. But if one wishes to move many atomswith atomic precision to create a nanodevice, such a technique might bepainfully slow. An alternative approach is the modification of the surfaceproperties from a distance to encourage the diffusion of the absorbed mol-ecules into desired patterns. The possibility of this mechanism was firstseen in stochastic surfaces models. The current and future work is focusedon the analysis of molecular dynamics models of metal surfaces and thetheoretical characterization of their interaction with external sources.

_______________________________________________________

Modeling Photophysics and Photochemistry inBiological SystemsPROFESSORS C. FAHRNI AND J. -L . BRÉDAS

Recent advances make ab initio and semiempirical methods applicable tothe photochemistry and photophysics of biologically relevant molecules.Processes being studied include the excited state properties of various flu-orophores for the design of cation-selective sensors (used for confocal andmultiphoton imaging microscopy of labile zinc and copper pools inlive cells).

Fundamental Forces of Molecular RecognitionPROFESSOR C. D. SHERRILL

Noncovalent interactions govern molecular recognition and biomolecularstructure. These interactions are explored through very high-level quantummechanical methods. The first definitive work on the simplest prototype ofaromatic pi-pi interactions, the benzene dimer, has been presented, andinvestigations continue on how substituents tune pi-pi interactions.Additionally, benchmark-quality results are obtained for other types ofnoncovalent interactions. This work provides a better understanding ofsupramolecular chemistry and improved models for biomolecules.

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Dynamics of Electronic Processes in π-Conjugated MaterialsPROFESSOR J. -L . BRÉDAS

The operation of organics-based electronic devices requires the motion ofcharge carriers and/or excitations along and between molecules or poly-mer chains. The dynamics of these processes are a key aspect determiningthe efficiency of the devices; it can be described at the microscopic scaleby electron-transfer theory and energy-transfer theory. Theoretical studiesare aimed at developing electron/energy-transfer methodologies appropri-ate for π-con-jugated systems and applying them to materials of interestfor device applications. These studies also characterize electronic couplingand vibrational coupling in organic, mixed-valence systems.

See also:

> Organic Chemistry Using Phase Transfer Catalysis, Near Critical Water, and Supercritical CO2, page 28, Professors C. Liotta and C. Eckert

> Computational Structural Biology, page 14, Professor S. Harvey

> Protein Folding and Ligand Binding, page 19, Professor R. Hernandez

Programs in computational and theoretical chemistry emphasize the

development of new methods and applications to current problems:

nonlinear optical properties, polymerization dynamics, molecular

recognition, organic/metal interfaces, protein folding, bond-breaking

reactions, and charge transport in conjugated electronic materials.

These are highly complementary to a wide variety of experimental

programs described elsewhere. In addition to numerous high-end

computer workstations, the School of Chemistry and Biochemistry

has a 58-processor Pentium 4/Operton cluster and a 154-processor

Intel EM64T cluster networked with a high-speed Infiniband inter-

connect for parallel computations.

Quantum Simulations of Molecules and MaterialsPROFESSOR K. BROWN

Many materials exhibit low-temperature phase diagrams that are oftendominated by quantum effects. These quantum effects are studied bybuilding a quantum simulator composed of trapped atomic ions. A quan-tum simulator will be exponentially more efficient than a classical simula-tion, making it possible to rapidly calculate the quantum mechanicalproperties of magnetic materials, superconductors, and molecules.

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Bond-breaking Reactions, Diradicals, and Non-dynamical CorrelationPROFESSOR C. D. SHERRILL

Theoretical methods are being developed to treat systems featuring morethan one electron configuration, where electronic structure techniques(Hartree-Fock molecular orbital theory, many-body perturbation theory,density functional theory) can fail. Applications include studies of hydro-gen transfer reactions, the role of diradical intermediates formed by anti-cancer agents, and the description of potential energy surfaces.

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Electronic Structure of Organic Semiconductors and Their InterfacesPROFESSORS J. -L . BRÉDAS, S. MARDER, J. PERRY, L . TOLBERT,AND M. WECK

Organic semiconductors (π-conjugated molecules, oligomers, and polymermaterials) are increasingly used as active elements in new generations ofplastic electronic devices such as light-emitting diodes, solar cells, or field-effect transistors. Computational studies aim to: determine the geometricand electronic structure of organic semiconductors in the ground state, inthe charged state, and in the excited state; evaluate the nature of theirinterfaces with metal electrodes or other organic materials; and designnew materials with enhanced performance. Attention is also paid to thedescription of single molecules that could be used as electronic compo-nents (i.e., molecular electronics). The theoretical investigations arebacked by strong collaborations with experimentalists, in particular withthose within the Center for Organic Photonics and Electronics.

ComputationalandTheoreticalChemistry




Advanced Mid-infrared Optical Sensor SystemsPROFESSOR B. MIZAIKOFF

Mid-infrared sensor systems operating in the spectral window from 220µm are particularly attractive for optical sensing because molecule-specificinformation is provided by stimulation of ground vibrational modes. Oneaim of this project is to miniaturize the light source (e.g., quantum cas-cade lasers), waveguide (e.g., integrated planar structures or hollowwaveguides), and detector (e.g., quantum well devices) to develop inte-grated devices for the determination of organic compounds in the liquidand gas phases. Applications focus on environmental monitoring ofvolatile organic compounds in surface and ground waters, and methane inseawater (gas hydrates).

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Microcantilever Array-based BiosensorsPROFESSOR L . BOTTOMLEY

Biosensor devices based on the nanomechanical motion of microcan-tilevers are an emerging sensor platform. Molecular adsorption on amicrocantilever shifts its resonance frequency and induces bending. Highselectivity in response is achievable through the incorporation of biomole-cular recognition elements into thin-film coatings on the cantilever. Thegoal of this research is to develop plastic microcantilever-array technologyfor biosensing applications. The intrinsic advantages of thermoplasticarrays include low-cost, high-yield mass-production techniques and anease with which the mechanical properties of the cantilever can be tunedto meet its intended application. Current effort is directed to the develop-ment of plastic microcantilever-based enzymatic assays.

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Label-free Electrochemical DNA Hybridization AssayPROFESSORS J. JANATA AND M. JOSOWICZ

Polypyrrole with surface-immobilized DNA exhibits characteristic cyclicvoltammograms in an aqueous buffer. The shape of the voltammogramchanges dramatically upon hybridization with complementary DNA. Thedifference voltammogram then serves as the tool for recognition of thehybridization step. The implementation of this principle in large-scale(10 x 10) microfabricated arrays is being developed as a tool for the rapiddiagnosis of infectious diseases.

Magnetic Quartz Crystal MicrobalancePROFESSOR J. JANATA

When placed in a magnetic field gradient, the resonant frequency ofthe quartz crystal microbalance with paramagnetic materials depositedon it changes according to the magnetic field strength. This effect isexpected to lead to the development of new sensitive instruments forthe measurement of the magnetic susceptibilities of materials such asorganic semiconductors.

See also:

> New Technologies for Live Cell Imaging, page 10, Professor C. Payne

> Cold Molecular Ions, page 9, Professor K. Brown

> Multifunctional Scanning Nanoprobes, page 26, Professors B. Mizaikoff and C. Kranz


> Fundamentals of Colloidal Assembly, page 7, Professor L. A. Lyon

> Atmospheric Chemical Kinetics and Photochemistry, page 28,Professor P. Wine

> Scanning Electrochemical Microscopy for the Investigation of Complex Biogeochemical Processes, page 28, Professors B. Mizaikoff and C. Kranz

AnalyticalChemistry

Research in analytical chemistry at Georgia Tech includes

sensor development, mass spectrometry, chromato-

graphic and spectroscopic techniques, atmospheric chem-

istry, toxic waste disposal, and bioanalysis. The research

spans all aspects of method development, preparation

of functional materials, device fabrication, and electronic

signal processing. Collaborative studies involve pharma-

ceutical chemists, electrical and nuclear engineers, and

atmospheric scientists from academic institutions,

government, facilities, and industry.

Bioanalysis with Bioresponsive MaterialsPROFESSOR L . A. LYON

The design of materials that respond to specific biological cues is an areaof intense interest. For example, a new class of bioresponsive hydrogelparticles has been developed for applications in label-free biosensing andbioanalysis. These microstructures simultaneously act as the biosensor’sscaffolding/immobilization architecture, transducer, amplifier, and alsoallow for broad tunability of the analyte concentration to which the parti-cle is sensitive. The particles are exceedingly resistant to false signals dueto non-specific binding because the particles’ bioresponsivity is dependenton the reversible displacement of antigen-antibody interactions. Futurework will include using the bioresponsive particles in specially designedthin-film constructs in conjunction with other analytical techniques tomeasure bioresponsivity.

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Mass Spectrometry and ProteomicsPROFESSOR F. FERNANDEZ

Proteomics, the scientific field dedicated to understanding the localiza-tion, identity, function, and interactions of proteins in biological systems,holds great promise for studying the molecular basis of different types ofdiseases important both in the United States (cancer, Alzheimer’s, dia-betes), and in developing countries (malaria, dengue fever, etc.). Massspectrometry is one of the central techniques in proteomics. The develop-ment of creative ways of studying large molecules (e.g., proteins) andsmall molecules (lipids, metabolites, drugs) by mass spectrometry, with anemphasis on ambient, miniaturized ion sources and millisecond-scale ionseparations will provide new avenues for making fundamental discoverieson the origin and treatment of disease.

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Design of Materials for CHEMFETsPROFESSORS J. JANATA AND M. JOSOWICZ

Gels of organic semiconductors in ionic liquids are formulated as selectivelayers to optimize the performance of solid-state chemical sensors, suchas chemically sensitive field-effect transistors. Metal nanoclusters areincorporated into such gels to provide specific binding sites and the layersare then applied to solid state CHEMFET gas sensing arrays.



Arene-Arene InteractionsPROFESSOR D. COLLARD

The electronic structure of arenes and polyarylenes is a result of conjuga-tion along a molecule and the effect of molecular packing. Access to com-pounds in which aromatic systems are held atop one another affords theopportunity to explore the influence of packing on the electronic structureof conjugated polymers, an important class of materials for electronic andoptical applications. These studies make extensive use of organic synthe-sis, electrochemistry, and spectroscopic techniques (UV-vis-near IR,ESR, fluorescence).

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Chemical Ecology and Chemical CommunicationPROFESSOR J. KUBANEK

The ecological roles and consequences of plant and animal chemical sig-nals in aquatic environments are tested in the laboratory and at field sitesaround the world to understand the mechanisms of chemical communica-tion between living organisms. Ongoing projects include: 1) harmful algalbloom toxin; 2) sex attraction and mate recognition among zooplankton;3) receptor-binding mechanisms by which fish taste sponge chemicaldefenses; 4) discovery of novel natural products with pharmaceuticalpotential from aquatic organisms; 5) chemical defenses of tropical algaeagainst marine pathogens; and 6) freshwater community structures medi-ated by plant antifeedant compounds. This research involves multiple col-laborations as part of an Institute-wide Signals in the Sea program thatsupports interdisciplinary activities for graduate students in chemistry,biology, and engineering.

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DNA–Photochemistry and Charge TransportPROFESSOR G. SCHUSTER

DNA is a remarkable molecule with the ability to self-recognize andorganize, which could result in the development of new materials.Oxidation of DNA generates a radical cation, which can migrate over longdistances through the DNA until it is eventually trapped at a GG step.Trapping of the radical cation causes irreversible reactions that may leadto mutation if not repaired. The efficiency of radical cation transportthrough DNA is much higher than had been anticipated, and experimentsare designed and carried out to understand and explore this effect.

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Two-photon ChemistryPROFESSOR S. MARDER

Dyes that simultaneously absorb two photons enable one to excite mate-rials with very high spatial selectivity only at the focus of a laser beam.Molecules with donor-acceptor-donor (D-A-D) and acceptor-donor-accep-tor (A-D-A) structural motifs exhibit exceptionally large two-photonabsorptivities. Two-photon absorbing molecules and materials with addi-tional chemical and optical activity are now being designed and synthe-sized that can be used as sources of radicals and acids, as photo-depro-tecting groups, and for biological imaging and sensing.

Alkynylated HeterocyclesPROFESSOR U. BUNZ

Highly alkynylated heterocycles are made through the intermediacy of1,4-diethynyl-2,3,5,6-tetraaminobenzene synthons. While the tetraamineis very unstable, semi-protected derivatives can be handled with ease.These materials promise to be molecular n-type semiconductors and inter-esting in thin-film transistor and LED applications, as well as precursorsfor carbon-rich solid-state materials.

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Photoacids, Photobiology, and PhotopolymerizationPROFESSOR L . TOLBERT

Certain molecules become strong acids upon irradiation and can be usedto initiate a variety of reactions, including proton transfer and photopoly-merization. The dynamics of proton transfer can be examined by time-resolved spectroscopy to develop structure-activity relationships betweenparticular substitution patterns in a photoacid and the excited-stateactivity. A particular class of proteins is being examined that representsa unique example of natural photoacids.

Research programs in organic chemistry include initiatives

involving the synthesis of complex molecules, synthetic

methodology, and mechanistic physical organic chemistry.

Projects range from studies of organic photochemistry to

bioorganic and polymer chemistry. There are dynamic pro-

grams in the discovery of new medicinal agents and new

polymeric materials. Facilities include well-equipped labo-

ratories for synthesis, the College of Sciences’ high-field

NMR Center, and a variety of other spectrometers and

chromatographic facilities.

Bioorganic Chemistry of Polyketide and NonribosomalPeptide AntibioticsPROFESSOR W. KELLY

Biosynthesis of these two categories of natural products is subdivided intothree discrete phases: biogenesis of any unique monomeric precursors;assembly of the peptide/polyketide polymer; and the tailoring modifica-tions required to impart the product with its biological activity. Enzymesrequired for construction of core molecular scaffolds, via biosyntheticallyunusual intramolecular cyclizations, appearing in families of metaboliteswherein the biological activity of a specific molecule is dictated by itsunique peripheral modifications, are of particular interest.

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Design of Novel DNA-intercalating Topoisomerase Inhibitorsas Antitumor and Anti-infective AgentsPROFESSOR A. OYELERE

Anthracylines make up a common class of topoisomerase-targeting anti-cancer agents. Key examples presently in clinical use include doxorubicinand daunomycin. However, use of anthracyclines is limited by severe sideeffects including acute and systemic toxicity. (All anthracyclines are cardio-toxic.) The primary objective of this project is to develop a broad spectrumof next-generation anthracycline antitumor agents with lower toxicity. Thismakes use of strategies to identify new surrogates for the anthracyclineglycone moiety.

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Bio-organometallic CatalystsPROFESSOR C. FAHRNI

The distribution of metal ions in seawater can be directly correlated withtheir abundance in biological systems. Consequently, palladium, rhodium,iridium, and platinum are not found in any naturally occurring metallopro-teins. Nevertheless, these cations are excellent catalysts for a wide varietyof organometallic reactions. Research is focused on combining the richchemistry of platinum metals with the advantage of proteins to catalyzereactions with high regio- and stereo-selectivity. Novel bio-organometal-lic catalysts are developed by the redesign of structurally well-character-ized proteins.

Organic Chemistry:BioorganicChemistry and New Materials


See also:

> Protease Inhibitors, page 13, Professor J. Powers

> Electronic Structure of Organic Semiconductors and Their Interfaces,page 18, Professors J.-L. Brédas, S. Marder, J. Perry, L. Tolbert, and M. Weck

> Self-assembled Copolymers, page 5, Professor M. Weck

> Biosynthetic Engineering, page 15, Professor W. Kelly

> Polyphilic Fluoroalkyl Conjugated Polymers, page 5, Professor D. Collard

> Biogenic and Bioresponsive Conjugated Polymers, page 6,Professor U. Bunz

> Threaded and Cyclic Macromolecules, page 6, Professor H. Beckham


> Organic Chemistry Using Phase Transfer Catalysis, Near Critical Water, and Supercritical CO2, page 28, Professors C. Liotta and C. Eckert

> Novel Synthesis of Biofuels and Biochemicals, page 29,Professor A. Ragauskas

> Oligonucleotide-Small Molecule Interactions, page 12,Professor A. Oyelere

Long-Range Energy Transfer in BiomaterialsPROFESSOR A.RAGAUSKAS

Recent studies suggest that the compact, network polymer nature oflignin allows for efficient energy transfer. The photoexcitation is rapidlydistributed to other thermodynamically favored sites within the matrix.Although the fundamental photochemical principles associated with thisphenomena are well established for synthetic linear polymers, the funda-mental photochemistry for lignin chemistry is lacking because of the lackof appropriate model compounds. The goal of this program is to synthe-size a series of unique polyaromatic dendritic model compounds to testthe fundamental hypothesis that energy transfer occurs in lignin-like structures.

_______________________________________________________

Organic ElectronicsPROFESSORS S. MARDER, M. WECK, L . TOLBERT, U. BUNZ,AND D. COLLARD

There is currently much interest in organic electronics, i.e., the fabricationand study of electronic and optoelectronic devices such as light-emittingdiodes, photovoltaics, and phototransistors, based on readily processed,low-cost, organic molecular or polymeric materials. A key requirement forthe further development of this field, and for the stimulus to develop newtypes of devices, is the availability of materials with enhanced mobilitiesrelative to those presently available, approaching that of amorphous sili-con. Accordingly, research is focusing on understanding charge transportin: transition-metal organometallic compounds, photo-cross-linkable holeand electron transport polymers, discotic liquid crystalline materials, andligand-functionalized nanoparticles and composites.

Georgia Tech’s programs in nanoscience and technology

span initiatives in the Schools of Chemistry and Bio-

chemistry, Physics, and Materials Science and Engineer-

ing, as well as other engineering disciplines. Materials

under investigation include metals, semiconductors, and

organics for use in applications as diverse as electron

and photonic devices, catalysis, and bioassays.

New Properties of Noble Metal NanoparticlesPROFESSORS M. EL-SAYED AND Z. L . WANG

Due to their small size, noble metal nanoparticles have very strong sur-face plasmon absorption in the visible region that is sensitive to theirshape. This is due to the coherent oscillation of the free electrons acrossthe particles from one surface to the other. This electronic excitationimparts unusual properties such as an enhancement of the fluorescenceyield by a factor of over a million in gold nanorods, and efficient heatingof the rod, causing it to melt in ~30 ps by absorbing ~60 fJ of photonenergy. Studies are focused on understanding the unusual new propertiesin these nanoparticles and their assemblies.

_______________________________________________________

Optical Properties of Individual NanoparticlesPROFESSOR R. DICKSON

Unique brightly fluorescing, photoactivated nanoparticles are preparedand characterized. Much brighter and more robust than organic dye mol-ecules, these advanced nanomaterials are utilized both as optical memoryelements and as photoactivated biological labels.

_______________________________________________________

Nanopatterning and Enhanced Film Growth UsingLow-energy ElectronsPROFESSOR T. ORLANDO

New approaches to film growth using low-energy electron beam-enhanced deposition are being developed. The new techniques currentlyfocus on growth of semiconductor surfaces such as SiC and are part of alarger-scale effort to produce devices based on nanographitic systems.The diffraction and inelastic scattering of low-energy electrons areexploited to produce nanopatterns on surfaces. This technique, developedby the Orlando group, is called diffraction in electron-stimulated desorp-tion (DESD). Efforts are also under way to advance the theoreticaldescription of DESD and experimentally develop DESD as a novel methodfor obtaining holographic 3-D images of nanostructures with atomic-scale resolution.

_______________________________________________________

Multi-photon 3-D Micro- and NanofabricationPROFESSOR J. PERRY

Two-photon laser excitation of photoactive materials can be used tofabricate 3-D micro- and nanoscale structures from polymeric, metallic,and semiconductor materials. Such structures are being developed withthe goal of fabricating and integrating highly functional photonicmicrodevices such as 3-D optical circuits, switches and routing devices,waveguide couplers, and microlasers. Activities in this area include thedevelopment of photoactive materials, ultrafast laser-based patterning,modeling and fabricating structures, and characterization of the opticalproperties of fabricated microstructures. Extension of this research into3-D patterning of biocompatible or biologically active materials is beingpursued with the goal of providing new tools and capabilities for tissue engineering.

Nanochemistry



Nano-biocompositesPROFESSOR A. RAGAUSKAS

Rod-like nanostructures have been synthesized in the past few years fromseveral polysaccharides including cellulose, chitin, and xylan. Nanocellulosepossesses a variety of unique properties such as crystallinity. Nanocelluloseparticles form a liquid crystalline chiral nematic phase that has potentialapplications in the design of novel nonlinear optics and electronic displayunits. In addition, nanocellulose crystals can be incorporated into syntheticpolymers including polyvinyl alcohol (PVA), poly(butylacrylate) styrene,and polypropylene, and the resulting biocomposites exhibit substantialimprovements in physical performance. Efforts continue in the developmentof new nano-biocomposites that exhibit enhanced physical properties andunique ultrastructures.

_______________________________________________________

Designed Bio-interfacesPROFESSORS L . A. LYON, M. WECK, AND A. GARCIA

Responsive biomaterials, based on microgel bioconjugates’ having multipleorthogonal functionalities, can be attuned to specific applications includingcellular targeting, controlled drug delivery, and the reduction of inflamma-tory responses to implants. Functionalities may include non-biofoulingmaterials, cellular recognition molecules, and degradable crosslinks. Furtherresearch involves the cell-directed assembly of hydrogel nanoparticles pos-sessing specific antigens or surface receptors. These films are then used todirect the growth and adhesion of cells at the interface. Another goal is tostudy cell proliferation on a microgel surface in order to design templatesfor assembling polymeric films. This approach will allow us to design sub-strates for evolving materials based on a cell’s response to the underlyinghydrogel nanoparticles.

Multifunctional Scanning NanoprobesPROFESSOR B. MIZAIKOFF AND DR. C. KRANZ

Microfabrication using focused ion beam (FIB) technology enables the inte-gration of micro- and nano-electrodes into atomic force microscopy (AFM)cantilevers. The benefits of merging AFM with SECM include the direct cor-relation of structural information with chemical surface activity atnanoscale lateral resolution. This concept is expanded by chemical modifi-cation of the electroactive area leading to imaging nanobiosensors, scan-ning amalgam nanoelectrodes, and tip-integrate potentiometric nanoelec-trodes (e.g., the pH nanosensor). Moreover, the combination of integratedAFM/SECM technology with nearfield scanning optical microscopy (NSOM)and confocal imaging techniques provides new insights for the investiga-tion of complex biological systems, including the imaging of enzymeactivity and characterization of cellular signaling processes.

_______________________________________________________

Controlled Growth of Oxide NanostructuresPROFESSOR Z. L . WANG

Nanowire- and nanotube-based materials have been demonstrated asbuilding blocks for nanocircuits, nanosystems, and nano-optoelectronics.Controlled growth of aligned oxide nanowires is important for many tech-nological applications. This research focuses on our recent progress ingrowing aligned oxide nanostructures and the characterization of theirproperties for applications in sensors, electron field emission, light emitting,spintronics, and mechanics.

_______________________________________________________

Targeted Drug DeliveryPROFESSOR L . A. LYON

Anti-cancer drugs target any rapidly dividing cells in the body, leading toharsh side effects such as hair loss, nausea, and fatigue. It is important todevelop ways to avoid healthy cells, and deliver the drugs only to the can-cerous cells. Hydrogel nanoparticles have been developed that specificallytarget cancer cells. The extensive landscape of synthetic and structuralmodifications that can be made to these nanostructures makes thempotentially generalizable to a wide range of targeting applications.

Nanomechanics of Nucleic Acids and ProteinsPROFESSOR L . BOTTOMLEY

The atomic force microscope can be used to correlate the mechanical prop-erties of individual biomolecules with their structure. Probe tips chemicallyfunctionalized with molecular recognition elements enable contact withobjects at specific loci. For example, when a single 5’ (or 3’) biotinylatedDNA molecule, covalently anchored on the opposite end to a surface, isbrought into contact with a streptavidin-coated cantilever, retraction of thescanner enables the direct measure of the molecule’s elasticity. Systematicvariation of the nucleic acid orientation and sequence affords correlation ofthe mechanical properties with the structure. When this experiment is per-formed in the presence of DNA-binding drugs and/or proteins, informationabout how these agents impact DNA elasticity is obtained.

_______________________________________________________

Piezoelectric NanogeneratorsPROFESSOR Z. L . WANG

Innovative nanotechnologies allow for the conversion of mechanicalenergy (such as body movement, muscle stretching), vibration energy (suchas acoustic/ultrasonic wave), and hydraulic energy (such as body fluid andblood flow) into electrical energy that can be used to power nanodeviceswithout using a battery. This has a huge potential impact in the miniatur-ization of integrated nanosystems by reducing the size of the power gener-ator and improving its efficiency and power density.

_______________________________________________________

Nanomechanics of Carbon Nanotubes, Nanosprings,and NanocoilsPROFESSOR L . BOTTOMLEY

The mechanical properties of carbon-based nanomaterials can be correlatedwith their structure using the atomic force (AFM) and transmission electron(TEM) microscopes. Nano objects, grown by chemical vapor deposition, arecovalently attached to the AFM probe tip using an electrical dischargemethod. Monitoring AFM cantilever deflection, oscillation amplitude, andresonance during the cycled movement of the scanner enables a directmeasure of the mechanical response to compression. By judicious selectionof the surface chemistry of the substrate the nano object is brought intocontact with, buckling, slip-stick motion, and adhesion of the nano objectcan be observed and quantified. This information will aid in the design ofnext-generation composite materials comprised of carbon nanotubes dis-persed in a polymeric matrix.

See also:

> Two-photon Chemistry, page 23, Professor S. Marder

> Self-assembled Copolymers, page 5, Professor M. Weck

> Magnetic Nanoparticles, page 17, Professor Z. J. Zhang

> Synthesis and Characterization of Nanocrystals and Arrays, page 8,Professor R. Whetten





Photoinduced Multielectron Chemistry for SolarFuels ProductionPROFESSOR J. SOPER

Catalysts for the conversion of solar energy into chemical fuels must cou-ple photoinduced 1e- excitation to fuel-forming 2e- bond-making andbond-breaking redox reactions. New molecular designs are being devel-oped for such photocatalytic multielectron chemistry. Current efforts targetthe basic science of water oxidation in photoinduced O-O bond-formingreactions and multielectron proton-coupled electron transfer (PCET) forH2 production. Experimental studies of reaction mechanisms are aug-mented by computation to guide the design of new metal catalystsand ligand architectures.

_______________________________________________________

Energy and Fuels from Renewable ResourcesPROFESSORS C. JONES AND A. RAGAUSKAS

With the high cost of crude oil and instability of world energy supplies,the need for fuels and chemicals from renewable feeds has never beengreater. The United States has a large biomass resource that can betapped as a “green” CO2 neutral energy source. New methodologies forbiomass dissolution and catalytic conversion into fuels such as hydrogenand alkanes are being developed.

_______________________________________________________

Planetary and Environmental Surface SciencePROFESSOR T. ORLANDO

Low-temperature ice surfaces are ubiquitous in the universe, and the reac-tions that occur on these surfaces are very important in atmospheric andplanetary surface science. The detailed dynamics involved in the interactionof small molecules and radiation with ice are being investigated to addressfundamental questions regarding the uptake and ionization of acids andsalts on model ice and “aerosol” surfaces. The subsequent photochemistry ofthese complicated surfaces and interfaces is then examined using quantum-state-resolved laser schemes. The interaction of radiation with low-tempera-ture ices governs the formation of planetary atmospheres such as thoseobserved in the Jovian system, and stimulated reactions on or within low-temperature ice can lead to the formation of pre-biotic molecules. Theresearch uses state-of-the-art surface science techniques to helpastronomers and planetary scientists unravel complicated data from theGalileo and Cassini space missions._______________________________________________________

Novel Synthesis of Biofuels and BiochemicalsPROFESSOR A. RAGAUSKAS

Improved conversion of lignocellulosic biomass into biofuels is a high-prioritynational research goal that will enhance the nation’s environmental perform-ance and national security. New studies take advantage of recent advancesin ionic liquids to develop new chemical reactions that will convert renew-able biomass lignin into high-value chemical components including phenolderivatives, polycarboxylate, and/or lignin fragments for fuel additives.Employing modern oxidative chemistry, these studies are directed at investi-gating novel catalytic oxidative chemistry with polyoxygenated aromaticstructures in ionic liquids.

Biotechnological Approaches for Production ofNew MaterialsPROFESSOR S. MAY

Biotechnology is increasingly incorporated into many industrial processesthroughout the world and many materials of the future will be producedusing advanced biologically based approaches. Advanced enzyme technol-ogy approaches are used to achieve the efficient and controllable enzy-matic synthesis of materials outside of living cells. One approach focuseson cell-free biocatalytic processes to overcome the severe limitationsimposed on precursor monomers by cell permeability and cell toxicity.Two major thrusts are: 1) enzymatic production of chiral, biodegradablepolyesters that possess novel functionalities and unique material proper-ties; and 2) enzymatic production of chiral polyamides with novelmaterial properties.

_______________________________________________________

BiocatalysisPROFESSOR A. BOMMARIUS

Projects in biochemical engineering include studies of biocatalysis, bio-transformations, and enzyme stability. This research seeks to find noveland improved biocatalysts for efficient processes, often to provide com-plex, enantiomerically pure compounds important in the life-scienceindustries. The approach involves the evolution of an imperfect enzyme,which serves as a template, into different directions of desired activity.These directions are tested, and different directed evolution protocols arecompared in the laboratory. Novel catalysts are also sought, especiallyredox enzymes and racemases, primarily through sequence analogy withthe help of databases. The function of several annotated oxidases hasbeen demonstrated with this technique. Lastly, the kinetic stability ofthese proteins is investigated so as to predict stability as a function ofmedia components.

Research in environmental chemistry is an interdiscipli-

nary program including traditional areas of chemistry

(physical, organic, inorganic chemistry) with other areas

of science and engineering (biology, chemical engineer-

ing, and earth and atmospheric sciences) at Georgia

Tech. Combined with projects directed towards the

development of sustainable sources of energy and other

resources, this area presents tremendous opportunities

to develop solutions for profound challenges faced by

humankind that relate to the economy, health, and

national security.

Atmospheric Chemical Kinetics and PhotochemistryPROFESSOR P. WINE

Chemical change in the atmosphere is driven largely by reactions of pho-tochemically generated free radicals. A variety of optical and mass spec-trometric techniques are employed to study important atmospheric chem-ical processes. Results provide input into models of atmospheric transportand chemical transformation that are employed to understand importantsocietal issues such as global climate change, stratospheric ozone deple-tion, urban air quality, and acid precipitation. The studies also aid inestablishing free-radical thermochemistry, and for testing rate theoriesand ab methods applied to open-shell systems. Areas of emphasisinclude atmospheric sulfur oxidation, radical-catalyzed destruction ofozone, aerosol formation and growth, chemistry of the cold upper tropo-sphere, and elucidation of the role of weakly bound radical-moleculecomplexes in atmospheric chemistry.

_______________________________________________________

Scanning Electrochemical Microscopy for the Investigationof Complex Biogeochemical ProcessesPROFESSORS B. MIZAIKOFF AND C. KRANZ

Scanning electrochemical microscopy (SECM) provides information on(electro)chemical processes occurring at the solid/liquid, liquid/liquidinterface with lateral resolution in the sub-micrometer range suitable fornon-destructive investigations of biological systems, e.g., biocorrosionprocesses occurring at microbe-mineral interfaces. This procedure allowsfor the analysis of dissimilatory Fe(III) reduction (a central component ofbiogeochemical cycling of Fe, including weathering of Fe(III)-containingclays and minerals), biomineralization of Fe(II)-bearing minerals such asmagnetite, and dissolution processes at microbe/mineral interfaces. Thisinterdisciplinary project is a collaborative effort with T. DiChristina(Biology), M. Taillefert (EAS), A. Fedorov (ME), and P. Hesketh (ME).

_______________________________________________________

Organic Chemistry Using Phase Transfer Catalysis, NearCritical Water, and Supercritical CO2

PROFESSORS C. L IOTTA AND C. ECKERTOne of the aims of “green chemistry” is to use environmentally benignchemicals to perform syntheses and other processes. At high tempera-tures and under pressure, carbon dioxide and water take on unique sol-vating powers that facilitate a number of processes that are not possiblein other media. The solvents are inexpensive, safe, and easy to remove.Phase transfer catalysts facilitate reactions between reagents in differentphases (solid-liquid or two-immiscible liquids). The mechanisms andapplications of this catalysis are investigated in order to develop mecha-nistic and computer models (in a collaboration with Professor R.Hernandez) for these heterogeneous processes.

EnvironmentalChemistry andSustainableTechnologies:Energy,BiorenewableResources,and “Green”Chemistry

See also:

> Oxygen Production in Plant Photosynthesis, page 14, Professor B. Barry

> Electron Transfer in Enzymes, page 9, Professor B. Barry

E. Kent Barefield Professor – Inorganic ChemistryAssociate Dean 404.894.3300 [email protected]

Bridgette BarryProfessor – [email protected]

Haskell W. BeckhamProfessor – Polymer [email protected]

Andreas BommariusProfessor – Biochemical [email protected]

Lawrence A. Bottomley Professor – Analytical Chemistry404.894.4014 [email protected]

Jean-Luc Brédas Professor – Computational

Physical ChemistryChair in Molecular Design and

Eminent [email protected]

Ken BrownAssistant Professor –

Physical [email protected]

Uwe BunzProfessor – Organic and

Polymer [email protected]

David M. CollardProfessor – Organic and

Polymer ChemistryAssociate Chair404.894.4026 [email protected]

Robert M. DicksonProfessor – Physical [email protected]

Donald F. DoyleAssociate Professor –

[email protected]

Charles A. EckertJ. Erskine Love Jr. Institute

Professor – Chemical Engineering

Director, Separations Center404.854.9344 [email protected]

Mostafa A. El-SayedJulius Brown Chair –

Physical ChemistryRegents’ Professor; Director,

Laser Dynamics [email protected]

Christoph J. FahrniAssociate Professor –

Bioinorganic and Organic Chemistry

[email protected]

Facundo FernandezAssistant Professor –

Analytical [email protected]

Steven HarveyProfessor and Georgia Research Alliance Eminent Scholar – Structural Biology

[email protected]

Rigoberto HernandezAssociate Professor – Computational Physical Chemistry

[email protected]

Nicholas HudAssociate Professor – Biochemistry

[email protected]

Jiri (Art) JanataProfessor and Eminent Scholar – Analytical Chemistry

[email protected]

Christopher W. JonesAssociate Professor – Chemical Engineering

[email protected]

Wendy Kelly Assistant Professor – Biochemistry404.385.1154 [email protected]

Nils Kröger Assistant Professor – Biochemistry404.894.4228 [email protected]

Julia KubanekAssistant Professor – Biological Chemistry

[email protected]

Charles L. LiottaRegents’ Professor – Organic Chemistry

Vice Provost for Research/Dean of Graduate Studies

[email protected]

L. Andrew LyonAssociate Professor –


Seth MarderProfessor – Organic [email protected]

Sheldon W. MayRegents’ Professor –

Biochemistry [email protected]

Alfred MerrillProfessor and Smithgall Chair

of Biology – [email protected]

Boris MizaikoffAssociate Professor –


Thomas M. OrlandoProfessor – Physical and

Analytical ChemistrySchool Chair

[email protected]

Adegboyega (Yomi) OyelereAssistant Professor –

[email protected]

Christine PayneAssistant Professor –

Physical [email protected]

Joseph PerryProfessor – Physical [email protected]

James C. PowersRegents’ Professor –

Biochemistry and Organic Chemistry

[email protected]

Arthur Ragauskas Associate Professor –

Paper [email protected]

William S. Rees Jr.Professor – Inorganic and

Materials [email protected]

Gary B. SchusterVasser Woolley Chair –

Organic ChemistryDean, College of [email protected]

C. David SherrillAssociate Professor –

Theoretical Physical Chemistry

[email protected]

Jake SoperAssistant Professor –

Inorganic Chemistry404.894.4022 [email protected]

Mohan SrinivasaraoAssociate Professor –

Polymer Chemistry404.894.9348 [email protected]

Laren M. TolbertProfessor – Organic [email protected]

Zhong Lin WangRegents’ Professor – Physical

ChemistryDirector, Center for Nano-

structure Characterization and Fabrication

[email protected]

Marcus WeckAssociate Professor – Organic

and Polymer [email protected]

Robert L. WhettenProfessor – Physical [email protected]

Angus P. WilkinsonProfessor – Inorganic [email protected]

Loren D. WilliamsProfessor – [email protected]

Paul H. WineProfessor – Physical [email protected]

C. P. WongProfessor – Material and

Polymer Chemistry404.894.8391 [email protected]

Z. John ZhangProfessor – Inorganic [email protected]

Information about the research interests of individual faculty may be found atwww.chemistry.gatech.edu.

The Faculty Descriptions of research programs appear on pages 4-229.



P

Chemistry and Biochemistry Buildings

Molecular Science and Engineering Building

(2006)

Ford EnvironmentalScience and

Technology Building

Petit Institute for Bioengineering and

Bioscience

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Tech Trolley, part of the campus shuttle system Legendary Yellow Jacket football

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Phone: Cameron Tyson, 404-894-8227E-mail: [email protected]

Brand new Campus Recreation Center

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Institute Communications & Public Affairs • T0725300

An equal education and employment opportunity institution


Atlanta: Showpiece of the SouthAtlanta is the nation’s southeastern hub of culture, science, technology,

education, medicine, and commerce. The city lies among the rolling

hills of northwestern Georgia at an altitude of 1,050 feet. It enjoys

mild winters, yet its altitude protects it from extreme heat. With a mod-

erate cost of living and a diverse population, the city offers numerous

dining and social establishments, summer festivals, and sporting

events.

Atlanta, home of the Martin Luther King Jr. Center for Nonviolent

Social Change, The Carter Center, and the U.S. Centers for Disease

Control and Prevention, consistently ranks among America’s most liv-

able cities. Peachtree Street, Atlanta’s central thoroughfare, originates

downtown and proceeds through the rich nightlife of the Midtown and

Buckhead neighborhoods. The Woodruff Memorial Arts Center houses

a concert hall, the Alliance Theater, and an arts college. The High

Museum of Art hosts exhibits of national and international significance

and maintains an outstanding permanent collection. The Fox Theatre, a

downtown landmark, regularly features Broadway road shows. The

Atlanta Symphony Orchestra and Chorus perform more than 100 con-

certs each season. Musical productions are performed in a diverse

array of clubs and concert halls throughout the city.

Outdoor activities abound in and around Atlanta. A drive of just a

few hours allows you to enjoy the Smokey Mountain National Park,

beaches on the Georgia and Florida coasts, and the Okeefenokee

Swamp National Park. Closer to home, Atlanta boasts the

Chattahoochee National Forest, Lake Lanier, and Lake

Allatoona, which host numerous water activities as well as

quiet retreats. Other sites of interest include the Underground

Atlanta shopping district, Zoo Atlanta, the Botanical Gardens,

and superb golf courses. Piedmont Park, located in Midtown

Atlanta, is one of America’s most prized urban parks.

Sports activity is constant in Atlanta, as the city hosts

numerous track and field, bicycle, and motor-sport competi-

tions. The 50,000-seat Turner Field is home to Braves base-

ball, while the Falcons NFL team plays in the Georgia Dome.

Basketball’s Hawks and the NHL’s Thrashers play in the nearby

Philips Arena.

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