Preliminary investigation of electros pun collagen and polydioxanone for vascular tissue engineering applications

Electrospun collagen alone does not provide the mechanical integrity necessary for tissue engineering applications. Thus, blends of polydioxanone (PDO) and collagen have been electrospun into nanofibrous scaffolds with novel compositions and structures as well as mechanical properties. PDO, a biodegradable synthetic polymer, serves to maintain the mechanical integrity of the scaffold, and collagen (specifically types I and III) is utilized in the electrospun blend to provide the native ultrastructure necessary for the desired cellular interactions. Polymer solutions of PDO and collagen (of one or both types) were electrospun to create randomly oriented, non-woven, fibrous scaffolds that were then analyzed via scanning electron microscopy and uniaxial tensile testing. The addition of collagen to PDO decreased the mean fiber diameter (compared to PDO alone), but there was no specific trend observed with the blended compositions (i.e. an increase in the percentage of collagen did not have a significant effect on mean fiber diameter, which ranged from 210 to 340 nm for the PDO/collagen blends). A comparison of the uniaxial tensile mechanical properties of the electrospun blends of PDO and collagen to those properties of vascular grafts currently in clinical use revealed that these electrospun mats can be tailored to match the basic mechanical properties of those prosthetics. Finally, human dermal fibroblasts were seeded onto some of the electrospun mat compositions. Those scaffolds containing collagen displayed favorable cellular interactions in terms ofbiocompatibility in that fibroblasts moved into the thickness of those scaffolds (whereas the cells merely migrated on the seeded surface of the PDO-only scaffold). One tissue engineering application of particular interest for such a polymeric blend is an off-the-shelf, bioresorbable, acellular small diameter (\u3c5 mm inner diameter) vascular prosthetic capable of in situ arterial tissue regeneration; these materials have the potential to achieve this desired response in vivo. Disclosure: Several authors have United States and International patents pending concerning technology presented in this manuscript, and this technology has been licensed to NanoMatrix,Inc, of which several authors have a financial interest