Vascular Tissue Engineering Utilizing Electrospun Matrices: Microscopic Evaluations

Abstract

The development of a seamless, collagen-based vascular prosthetic scaffolding (< 4 mm I.D.) has been accomplished using an electrospinning fiber production technique (Patents Pending). Electrospinning is the deliberate application of the phenomenon of electrostatic spraying which occurs when electrical forces at the surface of the polymer solution overcome the surface tension, creating a splay. The splay produces fibers with diameters in the nano-scale range (<500 nm). The collagen-based scaffold production method (flexible, quick, and simple) utilizes the splaying of the collagen-based solution from a nozzle to a grounded rotating mandrel (4 mm O.D. cylindrical mandrel for the preliminary vascular tissue engineering). in splaying, the solvent evaporates creating nano-scale fibers of polymerized collagen (and elastin in some variations). The collagen fibers are collected on the mandrel forming a cylindrical tube (media equivalent scaffolding). to date, mixtures of collagen containing Type I and 80:20 Type l/Elastin have been utilized to produce vascular scaffolds of various thickness (50 - 2,000 microns).