To create a polycaprolactone mesh which enables cell activity and seeks to eventually provide an...
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Transcript of To create a polycaprolactone mesh which enables cell activity and seeks to eventually provide an...
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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