Engineering of a small-diameter vascular prosthetic utilizing electrospun collagen and elastin nanofibers

Electrospinning is a fabrication process that uses an electric field to control the deposition of polymer fibers onto a target substrate. This electrostatic processing strategy can be used to fabricate fibrous polymer mats composed of fiber diameters ranging from several microns down to 100 nm or less. In this study, we describe how electrospinning can be adapted to produce tissue-engineering scaffolds composed of collagen and elastin nanofibers. Optimizing conditions for calfskin type I collagen produced a matrix composed of 100 nm fibers that exhibited the 67 nm banding pattern which is a characteristic of native collagen. The structural properties of collagen varied with the tissue of origin (type I from skin vs. type I from placenta), the isotype (type I vs. type III), and the concentration of the collagen solution used to spin the fibers. The same was done as a blend with elastin from bovine ligamentum nuchae. Electrospinning is a rapid and efficient process that can be used to selectively deposit polymers in a random fashion or along a predetermined and defined axis. Toward that end, our experiments demonstrate that it is possible to tailor subtle mechanical properties into a matrix by controlling fiber orientation and fixation time. The inherent properties of the electrospinning process make it possible to fabricate complex, and seamless, three-dimensional shapes. Electrospun collagen promotes cell growth and the penetration of cells into the engineered matrix. The structural, material, and biological properties of pure electrospun collagen and collagen/elastin blends suggest that these materials may represent a nearly ideal tissue engineering scaffold.