Release of Ketoprofen from Alginate Microparticles Containing Film Forming Polymers

985-989Ketoprofen-loaded alginate microparticles were prepared by dropping alginate-drug suspension, with or without aqueous colloidal polymer dispersions, into calcium chloride solution. The effect of various formulation variables on the physical characteristics of the microparticles was studied. While increase in the concentration of sodium alginate and aqueous polymer dispersions increased the sphericity of the microparticles, no appreciable change in the morphology was observed with variation in the concentration of calcium chloride and curing time. The mean diameters of the microparticles were influenced by all the variables. Drug entrapment efficiency approached nearly 100 per cent , except in those microparticles prepared by curing for longer time. In vitro release showed that drug release from the microparticles depended only on the concentration of alginate and the nature of aqueous colloidal polymer dispersions.