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.

ECM - main structural tissue of skin› Helps skin renew and generate› Provides signals to intercellular pathways

Engineered ECMs are known as scaffolds

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

Biocompatible polymer

Biodegradable at a rate that allows increased cell growth and stability

Easy to manipulate

Relatively low melting point - easy to use

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

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

Natural polymer that exhibits biocompatible and biodegradable qualities

Cellular binding capabilities

Anti-bacterial properties

High viscosity which limits electrospinning

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 kV

Vary voltage to create 9 meshes› 3 Voltages- 3 trials for each

20 kV 15 kV 25 kV

Examine mesh using Scanning Electron Microscope (SEM)

Culture fibroblast cells onto mesh

Observing cells› Inverted light microscope

Analyze cell growth› Cell counts in cells per unit area (mm2)› Means and standard deviations› ANOVA (Analysis of Variance) tests

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)

Analyze with SEM Culture fibroblast cells and seed into

meshes created Determine cell density Analyze with means, standard

deviations, and ANOVA tests

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

DateAcetic Acid Stir/Level Heat/Level Time Results

12/8/10 .5 Molar Yes /8 No

Approx. 1.5 hours Not Dissolved

12/8/10 Glacial Yes/8 No Approx. 1.5 hours Slightly Dissolved

12/14/10 Glacial Yes/9 No 3 hours Almost Completely Dissolved

12/20/10 Glacial Yes/5 Yes/520 minutes

Dissolved and then hardened

12/20/10 Glacial Yes/7 Yes/2 2.5 hours Dissolved, hardened by next class

12/20/10 Glacial Yes/5 No 3 hours Dissolved, still liquid next class

15 wt.% solution created› 17 g. acetic acid, 3 g. PCL

Electrospun› 5 mL syringe with bevel tip› Flow rate: .02??

Mesh created within 2 hrs.

Background Research Experimental Design ISEF (International Science and

Engineering Fair) Forms Started solutions Just began spinning

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