Development and Statistical Optimization of Sustained Release Gastro Retentive Floating Tablets of Cephalexin

The aim of present study was to formulate the sustained release floating tablets of Cephalexin (CPL) by direct compression method and optimized by Box-behnken Response Surface Methodology (RSM). A computer aided optimization technique was employed to investigate the formulation design by Box-behnken RSM (Design Expert Software version 8.0.7.1) to study the effect of the concentration of various polymer blends on the property of CPL gastroretentive floating tablets like floating lag time (FLT), cumulative percent drug release (%CDR). The independent variables investigated were polymeric concentrations (X1) and dependent variables were FLT (Y1), %CDR (Y2) in 0.1N HCl buffer at the end of 8 h. Results from precompression evaluation indicated that all the 17 and optimized formulation F18 were complied with the pharmacopoeial limits. The predicted value for FLT and %CDR obtained from software was compared with the experimental value of FLT and %CDR of optimized formulation F-18 and it was observed that the obtained experimental value was in very close agreement with the predicted value. The optimized formulation (F-18) gave good FLT and %CDR when compared to the 17 formulations.Key words: Cephalexin: Design Expert Software; Floating tablets; Optimization; Response Surface Methodology.