Tyler Crawford Shannon Daily Fabrication of an electrospun

Tyler Crawford Shannon Daily Fabrication of an electrospun nanofibrous scaffold for use in the field of tissue engineering

Purpose: To create a polycaprolactone mesh which enables cell activity and seeks to eventually provide an application in the field of tissue engineering toward biomimetic skin graft.

The Extracellular Matrix (ECM) ECM - main structural tissue of skin › Helps skin renew and generate › Provides signals to intercellular pathways Engineered ECMs are known as scaffolds

Electrospinning Ability to create scaffolds › Mimic the ECM (size and porosity) › High surface to volume ratio Easy to vary mechanical and biological properties through changing materials Flexible- allows cells to manipulate their environment

Polycaprolactone (PCL) Biocompatible polymer Biodegradable at a rate that allows increased cell growth and stability Easy to manipulate Relatively low melting point - easy to use

Polycaprolactone Clinically safe (FDA approval) Proven to have potential for scaffolds in relation to tissue regeneration › Has created scaffolds w/ ideal conditions High porosities Large amounts of surface areas

Additional Biochemical Material Adding another biochemical can: › Increase stress resistance › Provide better adhesion of cells to the final scaffold › Increase the potential for cell proliferation Biochemical should › Be a component of skin naturally › Must be able to be combined in a solution to be electrospun

Chitosan (CHT) Natural polymer that exhibits biocompatible and biodegradable qualities Cellular binding capabilities Anti-bacterial properties High viscosity which limits electrospinning

Experimental Design Procedure: Create control meshes of pure PCL › Solution= PCL and acetic acid (solvent) › Electrospin Starting parameters: 15 wt. % concentration, 20 cm from tip of syringe to collector plate, & 20 k. V

Procedure continued: Vary voltage to create 9 meshes › 3 Voltages- 3 trials for each 20 k. V 15 k. V 25 k. V Examine mesh using Scanning Electron Microscope (SEM) Culture fibroblast cells onto mesh

Procedure continued: Observing cells › Inverted light microscope Analyze cell growth › Cell counts in cells per unit area (mm 2) › Means and standard deviations › ANOVA (Analysis of Variance) tests

Procedure continued: Create solutions of PCL and chitosan Electrospin Vary concentration of chitosan to PCL ›. 5% CHT › 1% CHT › 2% CHT Total of 9 meshes (3 trials of each concentration)

Procedure continued: Analyze with SEM Culture fibroblast cells and seed into meshes created Determine cell density Analyze with means, standard deviations, and ANOVA tests

Data and Analysis: Data obtained: › Fiber diameter and pore diameter of mesh › Cell density amounts Analysis includes: › Means* › Standard Deviations* › ANOVA tests 3 comparisons *5 -7 measurements/areas for these methods

Data: Creating Solutions Date 12/8/10 Acetic Acid Stir/Level Heat/Level Time Results. 5 Approx. Molar Yes /8 No 1. 5 hours Not Dissolved Glacial Yes/8 No 12/14/10 Glacial Yes/9 No 12/20/10 Glacial Yes/5 12/20/10 Glacial Yes/7 Yes/2 Approx. 1. 5 hours Slightly Dissolved Almost Completely 3 hours Dissolved 20 Dissolved and then minutes hardened Dissolved, hardened 2. 5 hours by next class No Dissolved, still 3 hours liquid next class 12/8/10 12/20/10 Glacial Yes/5

Data continued: 15 wt. % solution created › 17 g. acetic acid, 3 g. PCL Electrospun › 5 m. L syringe with bevel tip › Flow rate: . 02? ? Mesh created within 2 hrs.

Data continued:

Progress Background Research Experimental Design ISEF (International Science and Engineering Fair) Forms Started solutions Just began spinning

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