Formulation and evaluation of sustained release microspheres of rosin containing aceclofenac

ABSTRACT

Aceclofenac was microencapsulated using rosin by o/w emulsion solvent evaporationtechnique. The effect of three formulation variables including the drugpolymer ratio,emulsifier (polyvinyl alcohol) concentration and organic solvent (dichloromethane) volumewere examined. The prepared batches were characterized for microspheres particle sizedistribution, encapsulation efficiency and in vitro release behavior. The study reveals thatdrugpolymer ratio had a considerable effect on the entrapment efficiency, however particlesize distribution of microspheres was more dependent on the volume of dichloromethane andpolyvinyl alcohol concentration rather than on the drug polymer ratio. Drug, polymerconcentrations were varied to obtain optimum release profile for sustaining the action of thedrug(AU)