Development of gastro retentive drug delivery system of cephalexin by using factorial design Prakash Rao, B. Ashok Kottan, Neelima Snehith, V.S. Ramesh, C. Floating drug delivery systems (FDDS) Factorial design Cephalexin (CFL) Fourier Transform Infrared Spectroscopy (FT-IR) Scanning electron microscopy (SEM) The objective of this research work was to formulate and optimize the floating drug delivery system containing cephalexin using 23 factorial design. Floating tablets were prepared by direct compression method incorporating HPMC K4M, xanthan gum, guar gum, sodium bicarbonate and tartaric acid as gas generating agent. The influence of independent variables like, polymer: polymer ratio, polymer type and tartaric acid on floating lag time and cephalexin release profile were studied. The diffusion exponent (n) of Krosmeyer Peppas for optimized formulation was found to be 0.635 which indicates the mechanism of drug release was anomalous transport. Floating lag time of optimized formulation was 1.50 min and remained buoyant for 24 hrs. Optimized formulation was checked for stability at 40ºC / 75% RH which was found to be stable. Scanning electron microscopy study revealed gel formation. FT-IR studies revealed that there was no chemical interaction between cephalexin and other excipients. 2013-07-05T09:54:13Z 2013-07-05T09:54:13Z 2009 journal article Prakash Rao, B.; et al. Development of gastro retentive drug delivery system of cephalexin by using factorial design. Ars Pharm, 2009; 50(1): 8-24. [http://hdl.handle.net/10481/27471] 0004-2927 http://hdl.handle.net/10481/27471 eng http://creativecommons.org/licenses/by-nc-nd/3.0/ open access Creative Commons Attribution-NonCommercial-NoDerivs 3.0 License Universidad de Granada, Facultad de Farmacia