Oxygen generating scaffolds for enhancing engineered tissue survival

Abstract

One of the continued challenges in engineering clinically applicable tissues is the establishment of vascularization upon implantation in vivo. Although the effectiveness of an enhanced angiogenic response using various growth factors has been demonstrated in many tissue systems, the rate of angiogenesis could not be accelerated. In this study we investigated whether incorporating oxygen generating biomaterials into tissue engineered constructs would provide a sustained oxygen release over an extended period of time. We examined whether oxygen generating biomaterials are able to maintain cell viability while also maintaining structural integrity of a 3-D construct. Calcium peroxide-based oxygen generating particles were incorporated into 3-D scaffolds of Poly(d,l-lactide– co–glycolide) (PLGA). The scaffolds were designed to generate oxygen over the course of 10 days and simultaneously maintain sufficient mechanical integrity. Scaffolds containing oxygen generating materials maintained elevated levels of oxygen when incubated under hypoxic conditions. Further, these biomaterials were able to extend cell viability growth under hypoxic conditions. These findings indicate that the use of oxygen generating biomaterials may allow for increased cell survivability while neovascularization is being established after implantation. Such scaffolds may play an important role in tissue engineering where currently oxygen diffusion limits the engineering of large tissue implants.