Development and in-vitro characterization of lornoxicam loaded ethyl cellulose microspheres prepared by emulsion solvent evaporation method

Advancement in drug delivery could come from innovating improvement to the existing drug delivery system. Lornoxicam (Lxm) loaded ethyl cellulose microspheres were prepared by emulsion solvent evaporation technique and also to investigate the effect of variations in drug concentration, polymer concentration, internal phase volume, continuous phase volume and emulsifier concentration on the particle size, shape, % yield, percent entrapment efficiency and in vitro drug release behavior. The scanning electron microscopy (SEM) revealed that microspheres had good spherical geometry with smooth surface. The result showed that the maximum yield of the microspheres was found to be 64.23 ± 0.25%, with particle size in the range of 64.24 ± 1.82 to 81.83 ± 3.43 μm and encapsulation efficiency was found to be in a range of 60.34 ± 1.63 to 71.61 ± 1.20%. The average particle size and entrapment efficiency of microspheres were enhanced with increasing polymer concentration but reduced with increasing internal phase volume, external phase volume and emulsifier concentration. In vitro release profile of microspheres was in the range of 75.65 ± 2.3 to 87.78 ± 2.3% at the end of 12 h. It was concluded that Lxm loaded ethyl cellulose microspheres formulation showed sustained effect over a period of 12 h. Key words: Ethyl cellulose, lornoxicam, microspheres, solvent evaporation, sustained release.