Soft Matter Nanotechnology Lab at CNR-NANO and University of Salento, Italy

The Soft Matter Nanotechnology Lab is led by Prof. Dario Pisignano at the Department of Mathematics and Physics “Ennio De Giorgi” of the Uni-versity of Salento and at the National Nanotechnology Laboratory of the Na-noscience Institute of CNR, in Lecce, Italy. Prof. Dario Pisignano is currently a faculty member (Associate Professor) at the University. The group’s primary research area concerns the application of micro- and nanotechnologies to soft matter, polymers, fluids and biomole-cules through highly interdisciplinary programs. The group aims to develop efficient technologies and methods in which organic materials and poly-mers can be patterned at the micro- to nanoscale, thus making them usable within devices for optoelectronics or biotechnology, without deteriorating the materials functional properties. The group’s research interests span from the fundamental physical properties of realized nanomaterials to technological applications. Soft lithographies1,2 and electrospinning3,4 to produce function-al polymer nanofibers1,3,4,5 are among the techniques most widely developed and applied. Realized devices include organic lasers6, nanogenerators based on energy harvesting5, and novel and optimized lab-on-chip architectures. In particular, polymer nanofibers are excellent building blocks for a wide variety of devices and for scaffolds for tissue engineering, so are currently at the focus of the group’s interests and also in the framework of a broad set of

international collaborations in Europe and USA. Prof. Pisignano also recently authored the book “Polymer Nanofi-bers” published by the Royal Society of Chemistry in their Nanoscience & Nan-otechnology Series (2013).

Some of the the group’s most recent research interests/projects include:

  The use of polymer nanofibers for building optimal scaffolds for tissue engineering of microvascular, renal and neuronal cells, including stem cells. Polymer nanofibers can be functionalized by extracellular matrix proteins or inorganic nanocrystals to enhance achievable bio-functionality. Other areas of applications of nanofi-ber-based scaffolds and membranes include catalysis and filtration.

  The development of innovative device platforms, such as electrically-tunable distributed feedback lasers based on organics, microfluidics for polymer particles synthesis and bacterial de-tection, nanofiber-based piezotronics and electronics.

NANO-JETS, coordinated by Prof. Pisignano is an Ideas-Starting Grant funded by the European Research Council, and targets the application of light-emitting polymer nanofibers in new lasers. The project aims to tackle the still unsolved issues of the electro-spinning process in terms of product control by means of the parameters affecting the dynamics of electrified jets.

There are currently Post-doc and PhD openings in all the research areas

above. Visit the NANOJETS project’s website to read more about their re-search.

www.nanojets.eu

1. L . Persano, A . Camposeo, F. Di Benedetto, R . Stabi le , A . M . Laera , E . P iscopie l lo , L . Tapfer, D. P is ignano, “CdS -polymer nanocomposites and l ight- emit t ing f ibers by in - s i tu e lec tron -beam synthesis and l i thography”, Advanced Mater ia ls , 5320 -5326, 24 (2012).

2 . S . C . Laza, M . Polo , A . A . R . Neves , R . Cingolani , A . Camposeo, D. P is ignano, “Two -photon cont inuous f low l i thography”, Advanced Mater ia ls , 1304–1308, 24 (2012).

3. Camposeo, I . Greenfe ld , F. Tantuss i , S . Pagl iara , M . Mof fa , F. Fuso, M . A l legr ini , E . Zussman, D. P is ignano, “Local mechanical proper t ies of e lec-trospun f ibers corre late to their internal nanostructure”, Nano Let ters , in press , DOI: 10.1021/nl4033439 (2013).

4. L . Persano, A . Camposeo, C . Tekmen, D. P is ignano, “ Industr ia l upscal ing of e lec trospinning and appl icat ions of polymer nanof ibers : a rev iew“, Macro -molecular Mater ia ls & Engineer ing , 504 -520, 5 (2013).

5. L . Persano, C . Dagdev iren, Y. Su, Y. Zhang , S . G irardo, D. P is ignano, Y. Huang , J . A . Rogers , “High per formance piezoelec tr ic dev ices based on al igned arrays of nanof ibers of poly[(v iny l idenef luor ide - co - tr i f luoroeth -y lene]”, Nature Communicat ions , 1633, 4 (2013)

6. Camposeo, P. Del Carro, L . Persano, D. P is ignano, “E lec tr ical l y tunable organic distr ibuted feedback lasers embedding nonl inear opt ical molecules”, Advanced Mater ia ls , OP221-OP225, 24 (2012).

Marquee goes here

SPECIAL FEATURELAST CALL FOR 2014 CALENDAR IMAGES SUBMISSION DEADLINE NOVEMBER 30TH 2013

The 2013 Calendar Competition image submission deadline is November 30th, 2013. In the following first two weeks of December the SoftMatterWorld team will face the difficult challenge of selecting the best 12 images to be be featured in the 2nd annual Soft Matter World Calendar.

We welcome all soft matter related art : whether it be computer simulated models or vibrantly colored microscopy images. This even includes artistic interpretations of soft matter science! Just remember the motto of the SMW Gallery : where soft matter science meets art.

Submit your image now to feature your research and artistic talents around the world. To submit an image visit the gallery at:

www.softmatterworld.org/gallery/

With only one month remaining we want to encourage our users to print out this special feature page and help spread the word by giving it to col-leagues, advisors and students.

3November 2013, Issue #58 2012/2013 Sof tmatterworld.org

Fig 3: The values of k-gamma distribution for the three experimental granule models (Square is monodisperse cuboidal, “X” is mon-odisperse brick-shape, and “+” is bidisperse cuboidal). The dotted line represents the control spherical granule packing.

Surfactant sculpting of biologically inspired hierarchical surfacesMelanie L. Morris, Lance M. Baird, Asmi Panigrahi, Michael C. Gross, Ryan M. Deacon and Jason J. Benkoski. Soft Matter, 2013, 9, 9857

Biological materials are hierarchical-ly organized. Man-made counterparts tend to be much simpler and are often out performed by naturally occurring materials. Imitating designs found in nature may lead to improvements in current soft material design.

Researchers at Johns Hopkins Uni-versity built on previous work they have done in nanoparticle self-assembly and devised a method of creating complex three-dimensional structures through the use of surfactant molecules in a single step. Called Fossilized Liquid As-

sembly (FLA), the method uses a bipha-sic oil and water system that is solidified by UV light. Surfactants were mixed with polydimethysiloxane-diacrylate (PDMS-DA) and applied to a glass slide. When submerged in water, the surfactants self-assembled into pores, bumps, and other surface structures. Additional features nucleated on the surfaces of these new surfaces, forming more complex arrangements. When UV light was applied, generation of new features ceased and the structure was set in place. These structures mim-

icked biological hierarchical surfaces. As seen in (Fig 2a), structures such as lung alveoli were imitated.

The group analyzed several factors that influenced the assembly. The longer the time allowed before application of the UV, the more pores and bumps nucleated. The group also found that viscosity controlled variation in the sizes of the bumps and pores. In addition, the authors state that the most important variable for assembly is the surfactant concentration. The concentration was observed to alter the structural motif entirely, rather than merely cause changes within a motif. Changing the concentration allowed them to create different structures via the same process using the same materials (Fig 2b-d).

The authors have simplified the creation of biologically inspired hier-archical structures. Rather than using successive stages and crosslinking, this method uses a single step that can be controlled by adjusting several vari-ables, potentially providing more ef-ficient mechanisms for artificial tissue generation.

The full article can be found here.

-Michael Lane

Structural Evolution of Cuboidal Granular MediaRobert F. Shepherd, Jacinta C. Conrad, Tapan Sabuwala, Gustavo G. Gioia and Jennifer A. Lewis

The packing properties of sand, com-prised of random assortments of gran-ules, as well as purely spherical granules have been previously investigated in some detail. However in this new paper, Jennifer A. Lewis of Frederick Seitz Ma-terial Research Laboratory, University of Illinois and her team worked with mono-disperse cuboidal, monodisperse brick-shaped and bidisperse cuboidal gran-

ules (Fig 3) to determine if these types of granules pack more efficiently than spherical granules. The granules used were formed from silica microspheres. A photocurable colloid-hydrogel sus-pension was used to create different shapes using stop-flow lithography. Granule size varied based on the shape. Each of the sampled shapes were agi-tated for varying times by horizontal

Figure 2a: SEM micrographs of various surface types and superf icially similar biological tissues. Figure 2b-d: SEM micrographs showing surface motifs at different concentrations of C12E4.

4November 2013, Issue #58 2012/2013 Sof tmatterworld.org

shaking in tubes. The k-gamma distribu-tion, which is the probability of distribu-tion that maximizes entropy, and the Voronoi minimum, representing the lowest possible space between each particle, were both calculated.

The team found that the brick-shaped and bidisperse cuboid k-gamma distributions and Voronoi minima behaved similarly, in that they took up less volume than both the monodisperse cuboidal and spherical shaped granules. On the other hand, the monodisperse cuboid took the most volume initially, but eventually with enough agitation the k-gamma distribution matched that of the

spherical shaped granules (Fig 3a-c). In industry, it is possible that the more compact-efficient granules comprised of brick-shaped or bidispersal cuboid granules may be adopted where

spherical granules are used, such as in shape folding molds or dies.

-Marcus Rice

Figure 3a-c: Scanning electron micrographs of the three experimental granule models used. Mon-dodisperse cuboidal (scalebar 150 μm), monodisperse brick-shaped (scalebar 500 μm) and bidisperse cuboidal (scalebar 50μm). Bidisperse cuboidal has two sets of identical shapes in two sizes. In the top left corner of each is the respective Voronoi volume outline (red) for the subset of granules shown (blue).

British Liquid Crystal Society Annual Winter Workshop this JanuaryThe British Liquid Crystal Society

(BLCS) will be holding its annual Win-ter Workshop this January at the Uni-versity of Hull, January 6th through 8th 2014. The (BLCS) Winter Workshop has been successfully operating annu-ally for many years now, and the basic aim is to introduce the various areas of liquid crystals to those researchers who are new to the field. Most people new to the field are recent post-grad-uate research students, but there are

many post-doctoral research fellows who may have been working in other areas and are new to liquid crystals.

The topics covered include but are not limited to:

  General Introduction to Liquid Crystals

  Synthesis of Liquid Crystals   Liquid Crystal Dendrimers and Poly-

mers   Lyotropic Liquid Crystals   Identification of Liquid Crystals

Registration is open on the conference website. For more information contact Dr. Mike Hird.

We hope you enjoy broWsing and come back soon

Linda S. HirSt & adam P. OSSOwSki

Join the Mailing List!