fabrication of an electrospun nanofibrous scaffold for use in the field of tissue engineering
TRANSCRIPT
Junior ResearchBy: Shannon Daily & Tyler Crawford
Fabrication of an electrospun nanofibrous scaffold for use in the field of tissue engineering
Purpose:
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.
Main Qualities to Replicate in the Creation of an Artificial 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
The Extracellular Matrix (ECM)
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
Electrospinning
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
Polycaprolactone (PCL)
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
Additional Biochemical Material
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
Potential Biochemical Polymers
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
Potential Polymers continued…
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
Potential Polymers Continued:
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
Experimental Design Progress: Procedure
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
Experimental Design Progress:Data and Analysis 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
References
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