Fabrication and Evaluation of Tinidazole Microbeads for Colon Targeting

The purpose of present investigation was to develop and evaluate multiparticulate system exploiting pH-sensitive property and specific biodegradability of calcium alginate microbeads, for colon-targeted delivery of Tinidazole for the treatment of amoebic colitis. Calcium alginate beads containing Tinidazole were prepared by ionotropic gelation technique followed by coating with Eudragit S100 using solvent evaporation method to obtain pH sensitive microbeads. Various formulation parameters were optimized which included concentration of sodium alginate (2% w/v), curing time (20 min) and concentration of pectin (1% w/v). All the formulations were evaluated for surface morphology, particle size analysis, entrapment efficiency and in-vitro drug release in conditions simulating colonic fluid in the presence of rat caecal (2% w/v) content. The average size of beads of optimized formulation (FT4) was found to be 998.73±5.12 μm with entrapment efficiency of 87.28±2.19 %. The invitro release of Eudragit S100 coated beads in presence of rat caecal content was found to be 70.73%±1.91% in 24 hours. Data of in-vitro release was fitted into Higuchi kinetics and Korsmeyer Peppas equation to explain release profile. The optimized formulation (FT4) showed zero order release. It is concluded that calcium alginate microbeads are the potential system for colon delivery of Tinidazole for chemotherapy of amoebic infection.