Poly(butyl methacrylate-co-methacrylic acid) tissue engineering scaffold with pro-angiogenic potential in vivo

A poly(butyl methacrylate-co-methacrylic acid) (BMA-MAA) scaffold was fabricated by an in situ polymerization solvent casting/particulate leaching technique. It displayed high porosity (85-90%), pore interconnectivity, and a pore size range of 100-650 microm. Compression testing of the scaffolds demonstrated a dependence of the compressive stiffness on several fabrication variables including the ratio of monomer to salt used during the polymerization, the degree of salt fusion, and the choice of alternative comonomers to BMA. Subcutaneous implantation of BMA-MAA scaffolds in mice revealed an increased level of histological angiogenesis in tissue invading the pores of the scaffold compared to a BMA control, consistent with the prediction that methacrylic acid (MAA) containing copolymer beads are angiogenic in a wound healing context. At postoperative day 21, the capillary density in the BMA-MAA scaffolds was 56 +/- 13/mm(2) as compared to 32 +/- 8/mm(2) for the BMA scaffolds. With further investigation, it is expected that this biomaterial capable of eliciting an angiogenic response will have widespread application in tissue engineering.