Fabrication and In-Vitro Evaluation of Sustained Release Aceclofenac Microspheres by Emulsion Solvent Evaporation Technique

Sustained release microspheres of Aceclofenac, a superior NSAID were fabricated by W/O emulsion solvent evaporation technique using ethyl cellulose (Ethocel 20 cps) as release retarding agent to provide it's analgesic and anti-inflammatory action for prolong period of time. Preformulation studies revealed Aceclofenac and ethyl cellulose were satisfactorily compatible without any change in the chemical nature of the drug. Microspheres were prepared at a fixed stirring rate of 1000 rpm. SEM study showed that the microspheres were spherical and uniform in shape with rough outer surface. The maximum loading efficiency of microspheres was found to be 88.66%. However, on increasing the polymer concentration the loading efficiency was increased. In-vitro drug release showed that on increasing polymer concentration the drug release of all the formulations were gradually decreased and the formulations followed Korsemeyer-Peppas kinetics. Release mechanisms followed non-Fickian model. Mean dissolution time (MDT) was calculated and found to be affected by core to polymer ratio.