91DESIGN AND CHARACTERIZATION OF MICROSPHERE CONTAINING ANTI-TUBERCULAR DRUG BY SOLVENT EVAPORATION METHODMicrosphere is a term used for small spherical particles, with diameters in the micrometer range (typically 1μm to 1000μm (1mm)). Microspheres are sometimes referred to as microparticles. In this Research the microsphere are formulated by solvent evaporation method and optimized by various product and process variables. Particle size, zetapotential, polydispersity index are the optimization parameters which plays a vital role in selection of optimized formulation for the further research . In this research six formulation of microsphere was formulated by altering the concentration of polymers like Chitosan and Sodium alginate. For all the formulation Percentage Yield, Drug Content, Entrapment Efficiency, Invitro release kinetics studies, Invitro drug release and stability studies are carried out. Among all the formulation S3 Rifampicin microsphere was optimized as best formulation based on the following parameters like Particle size, Zetapotential and Polydispersity index viz., 724.2 µm, -32.4 mV and 0.502, which shows the particle size was in range with good stability and uniform dispersibility of particle among phase. Further evaluation studies of S3 formulation shows better release characteristics and thus it was concluded that the microsphere formulated by solvent evaporation method was an optimized formulation technique and also chitosan was selected as a suitable polymer for formulation of microsphere by solvent evaporation methodgvelrajan@gmail.comResearch522015Microspheres,Solvent evaporation method,Lyophilization,Sodium alginate,ChitosanP.Bharathidhasan,G.VelrajanProf& Head, Dept of Pharmaceutical Chemistry, A.K.College of Pharmacy, Krishanan kovil 626190, Tamilnadu, India.,Dept of Pharmaceutics, S.S.R.College of Pharmacy, Mahabubnagar. Andhra Pradesh, India