Controlled release alginate-based microparticulate systems for drug delivery and chemoembolization

Abstract

Alginate as particulate carriers has the limitation of rapid drug release due to the porous alginate matrix. The main objective of this study was to develop controlled release alginate microspheres. A novel liquid phase coating (LPC) technique was developed to produce polymer-reinforced alginate microspheres. Composite microspheres prepared by a multiple emulsion technique were also developed. Optimized formulations with good physicochemical properties were successfully produced and studied. The coated microspheres prepared with LPC showed markedly reduced drug release compared to the uncoated control. The release mechanism and rate were affected by the type of polymethyl methacrylate, core:coat ratio and dissolution media. Drug release rate of poly (lactic-co-glycolic) acid (PLGA)-alginate microspheres was also successfully controlled by changing PLGA content in the alginate microspheres. Norcantharidin-loaded PLGA-alginate microspheres markedly increased the survival time of rats with transplanted hepatoma showing the potential of the microspheres as chemoembolization agent in the treatment of liver cancer.