Fabrication of an electrospun nanofibrous scaffold for use in the field of tissue engineering

To create a nanofibrous mesh consisting of polycaprolactone and another biological polymer which enables cell activity and seeks to eventually provide an application in the field of tissue engineering toward a biomimetic skin graft.

 Protection from infection  Prevent fluid/heat loss  Ability to support and maintain tissue growth  Skin properties › Friction & elasticity  For easy movement and manipulation

 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

 Ability to create scaffolds › mimic the ECM in size and porosity › Have high surface to volume ratio  More space for cells to attach and grow  Increases biocompatibility  Easy to vary mechanical and biological properties through changing materials  Flexible- allows cells to manipulate their environment

 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  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

 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

 Collagen › Advantages  biodegradable and biocompatible  plays important role in tissue formation › Disadvantages  Very expensive  complex handling properties  Gelatin › Advantages  naturally derived from collagen, similar properties  Cost efficient and easy to manipulate › Disadvantages  can provoke inflammatory response  Poor electrospinnability unless combined with specific solvents

 Hyaluronic Acid › Advantages:  Excellent biocompatibility and biodegradability  Main component of ECM › Disadvantages  High viscosity, surface tension, and water retention make it difficult to form uniform sized fibers  Elastin › Advantages  Provides elasticity to skin- essential for this skin quality › Disadvantages  highly insoluble  Potential health risk  Fibrinogen › Advantages  Essential for wound healing  Promotes cell migration and cellular interaction › Disadvantages  difficult to control matrix properties

 Alginate › Advantages  Good for health reasons (low toxicity, immunogenic)  Low cost › Disadvantages  Poor spinnability (possibly be fixed with addition of a synthetic polymer)  Chitosan › Advantages  natural polymer, biocompatible and biodegradable  Cellular binding capabilities  Accelerates wound healing  Anti-bacterial properties › Disadvantages  high viscosity limits spinnability  Fibers can swell in aqueous solution- need to be cross linked to maintain structural qualities

 Create solutions of PCL and other polymer varying the concentrations  Spin these solutions creating nanofilament meshes  Analyze meshes for fiber and pore qualities using scanning electron microscope  Culture fibroblast cells and seed into meshes created

 Data obtained will include: › Fiber diameter and pore diameter of the mesh › Concentration of the chemical › Amount of cell activity throughout mesh  Analysis will include: › For what concentration of chemical did the most cell activity occur

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