2.  ECM - main structural tissue of skin › Helps skin renew and generate › Provides signals to intercellular pathways  Main components › Glycoproteins (such as collagen) › Proteoglycans › Hyaluronic Acid  Engineered ECMs are known as scaffolds

3.  Ability to create scaffolds › Mimic the ECM in size and porosity › Have high surface to volume ratio  Easy to vary mechanical and biological properties through changing materials  Flexible- allows cells to manipulate their environment

4.  Biocompatible polymer  Biodegradable at a slow enough rate to allow increased cell growth and stability  Easy to manipulate  Relatively low melting point - easy to use

5.  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

6.  Much research has shown that 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

7.  Natural polymer that exhibits biocompatible and biodegradable qualities  Cellular binding capabilities  Anti-bacterial properties  High viscosity which limits electrospinning

8.  Good for health reasons (low toxicity, immunogenic)  Low cost – easily obtained  Poor spinnability - possibly fixed with addition of a synthetic polymer

9. To create an optimal nanofibrous mesh consisting of PCL and another biological polymer (Chitosan/Alginate) 1) To determine which mesh best cultures cells on the meshes 2)

10.  By combining PCL with another biological polymer, an electrospun mesh can be created that mimics the ECM, exhibits optimal biocompatibility, and encourages cell attachment and proliferation

12. Independent Variables Analyzing method of meshes (AFM in HCI vs SEM in AOS) Type of cell used (Drosophila in HCI vs Fibroblast in AOS) Dependent Variables: Microscope image produced (Resolution, magnification) Cell growth Controlled Variables Material spun - PCL Spinning conditions of PCL mesh (Applied voltage, flow rate, tip-to- collector distance, concentration)

13. AOS: Spin PCL; vary spinning conditions HCI: Replicate spinning conditions AOS: Observe mesh under SEM and grow Fibroblast cells on PCL mesh HCI: Observe mesh under AFM and grow Drosophila cells on PCL mesh

14.  Baseline can be set for comparison of images › For the Second stage: microscope used › For the Third stage: cells used  Control image- image X

16. Independent Variables Secondary material used when spinning meshes Conditions for spinning (Applied voltage, flow rate, tip-to- collector distance, concentration) Dependent Variables: Quality of nanofibers (Porosity, diameter, number of beadings) Controlled Variables Primary material used when spinning meshes – PCL Method of combining chemicals (chemically) Mesh shown in Image X (used for comparing other meshes)

17. AOS: Spin PCL-Chitosan mesh; vary spinning conditions HCI: Spin PCL-Alginate mesh; vary spinning conditions AOS: Observe under SEM, compare with Image X HCI: Observe under AFM, compare with Image X

19. Independent Variables Different types of meshes produced PCL-Chitosan mesh in AOS PCL-Alginate mesh in HCI Dependent Variables: Rate of cell growth (Cell size, number of cells) Overall cell adhesion to mesh Controlled Variables Conditions for cell growth (Cell characteristics, surrounding conditions)

20. HCI: Attach Drosophila cells to every PCL-Alginate mesh AOS: Attach Fibroblast cells to every PCL-Chitosan mesh Observe meshes under inverted light microscope to see if cells successfully attached to meshes

21. Compare number of cells per unit area for each mesh and cell sizes Derive rate of cell growth from comparing initial state of cells and final state of cells

22.  Triplicates created  Conclusion can be drawn based on rate of cell growth measured

23. November/ December AOS: Start electrospinning pure PCL mesh begin finding parameters; analyze mesh HCI: Look into research for cells (Drosophila vs Fibroblast) and other areas January AOS: Attach cells on pure PCL mesh; analyze cells HCI: Replicate parameters from AOS counterparts to spin PCL mesh

24. February AOS: Start electrospinning solutions of Chitosan and PCL HCI: Replicate parameters from AOS counterparts to spin PCL mesh; analyze mesh March AOS: Vary spinning conditions, scan meshes HCI: Attach cells on pure PCL mesh and analyze cell growth

25. April/May AOS: Grow cell culture on PCL-Chitosan meshes; Analyze cells HCI: Start electrospinning PCL-Alginate mesh; Vary spinning conditions June/July AOS: Compare images HCI: Grow cell culture on PCL-Alginate meshes; Analyze cells

26. August HCI: Compare images AOS and HCI: Come together to compare results on both sides (PCL-Chitosan mesh vs PCL-Alginate mesh)

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