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V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsDrug support and release systems, Ghent University, Department of Textiles

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Drug support and release systems

V.A. Nierstrasz and L. Van Langenhove

Department of Textiles, Ghent University,Technologiepark 907, 9052 Zwijnaarde (Gent)Belgium

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsDrug support and release systems, Ghent University, Department of Textiles

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Department of Textiles

P. Kiekens (head of department)chemical processes in textiles

K. De Clerckfibre morphology, colour and colour application

G. Schoukenspolymer technology

L. Van Langenhovefibrous structures, smart textiles

V. Nierstrasz biotechnology

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Special fibres and yarnsSpider silk

Artificial turf

Cotton

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

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Structure – function relationship of spider silk

(Visco-)mechanical properties:‣ unique combination of high strength and high strain ‣ tensile properties and hysteresis

Structural properties:‣ amino acid composition‣ FT-Infrared & FT-Raman spectroscopy‣ solid state NMR spectroscopy‣ thermal analyses (DSC, TGA, TMA)

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

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Spider silk in tissue engineering

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

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Electrospinning

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

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Nanowebs

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

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Applications of nanofibres

Wound dressingsSlow release (medical, tooth care)

Different polymersFilters (gas, liquid)Technology developer: Ph. Westbroek

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

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Release kinetics

zero-order release

time

burst release

9V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

Diffusion from a polymer matrix

From L. Brannon-Peppas, 1997

Often burst-release

Electrospinning of PLA (Zhang 2003&2005)

•41 kV, SDBS ->diameter 0.68-1.35 µm, •32 kV, PPO-PEO->diameter 0.34-1.35 µm.

Proteinase K → zero order kinetics!

10V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

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Applications of nanofibres

Wound dressingsSlow release (medical, tooth care)

Different polymersFilters (gas, liquid)Technology developer: Ph. Westbroek

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

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• Current research focuses on chemical methods

• Use of enzymes is a relatively unexplored

• Major advantage of enzymes: high specificity

• Concerted multi-disciplinary approach.

• UGent expertise

• Challenge:

Biotechnological or chemo-enzymatic approaches

for fucntional materials

Biotechnology instead of chemical processes

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

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• BIOTIC: Biotechnologically functionalised materials

Project contributes to bio-based economy

* Novel processes for textiles exhibiting the desired functionalities.* Novel enzyme technology for nano-structuring and functionalisation of surfaces.

AcknowledgementsWork is supported by a grant of the European CommissionFP7 Grant Agreement Number PIEF-GA-2008-219665

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

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NO BUG

• Incorporation of bio-active compounds → insectrepellent textiles

• Problems to solve:‣ Toxicity of current repellents‣ Limited duration of effectiveness

• approaches: ‣ Novel repellents‣ Novel release systems (micro-capsules, multi-layer

systems, …)

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

N BUGN BUG

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Sensors and actuators

Intelligent textiles:• (semi)-conductive materials for active textiles• (electro)chemical coating of metals and polymers• special textile structures• modelling and design of electronic textiles

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

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Sensors and actuatorsobjective sensors:

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

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Objectives actuators:Control release (electroporation, iontophoresis, ...)Heating and coolingElectro stimulation:• Modelling of current density• Design of electrodes• Testing of prototypes

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

Sensors and actuators

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Sensors and actuators

Weaving:Modelling of insertionYarn preparationIncorporation of optical fibresDesign of complex structures

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

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Sensors and actuatorsTextile components: materials

Kevlar with polypyrrol copper gold coating

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

Textile components: structures

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Sensors: * Textrodes* Respibelt * Sweat

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

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Colour changing materials: triggers like temperature (thermochromism), light (photo-chromism), electricity (electrochromism), pH (halochromism) , …

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

Sensors and actuators

pHx pHy

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsDrug support and release systems, Ghent University, Department of Textiles

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Drug support and release systems

V.A. Nierstrasz and L. Van Langenhove

Department of Textiles, Ghent University,Technologiepark 907, 9052 Zwijnaarde (Gent)Belgium

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Topics:Incorporation of biocatalysts into synthetic and

biopolymeric fibres for functional textilesEnzymatic surface modification of synthetic fibres for

functional textiles

V.A. Nierstrasz, Ghent 3rd of June 2010, Biomedical Textiles Seminar, BrusselsGhent University, Department of Textiles

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