Surface modified poly(L‐lactide‐co‐ε‐caprolactone) microspheres as scaffold for tissue engineering

Abstract

P-15 modified poly(L-lactide-co-epsilon-caprolactone) (PLCL) microspheres were investigated as scaffolds for tissue engineering applications. PLCL copolymer was synthesized by ring opening polymerization and was composed of a soft matrix of mainly epsilon-caprolactone moieties and hard domains containing more of L-lactide units thus exhibiting a rubber like elasticity responsible for providing mechanical strength to scaffolds. Microspheres were fabricated by solvent evaporation method and surface modified with P-15, a synthetic analogue of collagen. These were then evaluated for cell adhesion, ECM formation and cell proliferation. Anchorage dependent cell lines LLCPK-1 and L6 were seeded on PLCL microspheres (unmodified surface activated microspheres) and P-15-PLCL microspheres (P-15 modified microspheres). P-15 modified microspheres showed significantly higher cell adhesion and viability than unmodified microspheres. Scanning electron microscopy also revealed copious amount of extra-cellular matrix production by P-15. Initial results of cell culture experiment on two different cell lines suggested that the growth of LLCPK-1 in a 3D environment with P-15 modified microspheres is via spreading and flattening on the surface of scaffold followed by formation of a sheet-like structure while L6 grew in the form of multilayered structures with formation of interparticulate cellular bridges. The 3D moldable nature, combined with modification of surface chemistry with cell adhesion molecules such as P-15 to enhance proliferation of epithelial cells and myoblasts, recommends further investigation of P-15-PLCL microspheres for production of an ideal scaffold for soft tissue engineering.