Preparation and Characterization of Simvastatin Loaded PLGA Microparticles for Tissue Engineering Applications

Simvastatin has been reported to promote osteoblastic activity and inhibit osteoclastic activity. The successful use of simvastatin to promote in vivo bone formation depends on the local concentration, and there have been continuous efforts to find an appropriate delivery system for local delivery. Controlled drug delivery approaches based on microparticles could be a promising approach for sustained-localized delivery of simvastatin. In this study, simvastatin-loaded PLGA microparticles were prepared by using a modified single emulsion-solvent evaporation method. Uniform, spherical simvastatin loaded PLGA microparticles of size below 10μm were produced by adopting three different drug polymer ratios such as 1:40, 1:20 and 1:10 with encapsulation efficiency above 85%w/w irrespective to the drug polymer ratio and maximum simvastatin loading within PLGA microparticles was observed at drug polymer ratio of 1:10. Two stage release of simvastatin from microparticles was observed for 45 days, illustrating a controlled release. Simvastatin loaded PLGA microparticles are compatible with hFOB cells and induced in vitro bio-mineralization during 11 days treatment. These studies illustrate the feasibility of achieving local delivery of simvastatin to induce in vivo bone formation activity by suitably engrafting simvastatin loaded microparticles within porous scaffolds.