Abstract

FORMULATION AND EVALUATION OF ETHAMBUTOL MICROSPHERES

V. Viswanath* and Shaik Kaleem Ahammad

ABSTRACT

Emulsion cross linking method can be successfully employed to fabricate Ethambutol microspheres than Ionotropic gelation method. The technique provides characteristic advantage over conventional microsphere method, which involves an ―all-aqueous‖ system, avoids residual solvents in microspheres. Other methods utilize larger volume of polymer, uneasy in dropping through syringe, air pollution, toxicity and difficult to remove traces during filtration. FT-IR spectra of the physical mixture revealed that the drug is compatible with the polymers and copolymer used. Micromeritic studies revealed that the mean particle size of the prepared microspheres was in the size range 528μm to 644μm. Increase in the polymer concentration led to increase in % Yield, % Drug entrapment efficiency, Particle size, % swelling and % Mucoadhesion. Floating microspheres of drug with HPMC and Ethyl cellulose were buoyant while those with Eudragit S 100 showed greater buoyancy. Invitro drug release decreased with increase in the polymer and copolymer concentration.

Keywords: Ethambutol, Ionotropic gelation technique, Floating Microspheres, Eudragit S100, In vitro drug release studies.