FORMULATION AND IN-VITRO EVALUATION OF HPMCP-MICROENCAPSULATED DRUG-RESIN COMPLEXES FOR SUSTAINED-RELEASE OF DICLOFENAC

Microcapsules containing diclofenac-resin complexes were prepared by a non-aqueous emulsion method using hydroxypropyl methylcellulose phtha late (HPMCP). The effect of the addition of various surfactants on the characteristics of microcapsules including resin particles with diffe rent degrees of crosslinking, was investigated. The microencapsulation process was evaluated with respect to total yield and coat to core ra tio, and the microcapsules with respect to particle size and dissoluti on efficiency. Statistical analysis of the results demonstrated that b oth the degree of crosslinking and the presence of the polymer coating significantly retard release, indicating that the effect of the type of surfactant on the release rate is inappreciable.