Aim: The present research work involves the development and optimization of an in-situ gel forming formulation by face centered central composite response surface design methodology to increase buoyancy and controlled release of a novel antidiabetic drug; Canagliflozin hemihydrate, having absorption window in upper part of gastrointestinal tract. Materials and Methods: The drug and excipient compatibility studies were performed by subjecting to Fourier Transform Infra-red spectroscopy and Differential Scanning Calorimetry analysis. Nine primary formulations suggested by Design Expert software were formulated and subjected for the evaluation by measurement of rheological properties, buoyancy studies, drug content and in-vitro drug release studies. The optimization method adopted in the present study was face centered central composite response surface design. Result: The effect of two independent factors namely concentration of sodium alginate and concentration of gas generating agent calcium carbonate on responses like floating lag time, viscosity and in-vitro drug release were considered for the optimization by plotting three dimensional surface response plots. The results of these studies were subjected to analysis by software to obtain an optimized formulation. The software suggested the optimized formulation must consists of 0.868 % of sodium alginate and 0.957 % of calcium carbonate and these compositions are much near to the composition of SF5. Conclusion: By considering the effect of calcium cations on the gelling properties of various concentration of sodium alginate, it was concluded that the effective gelling was achieved in the formulation comprised of 1 % sodium alginate with 0.5 %, 1.0 % and 1.5 % of calcium carbonate.
Key words: Gastric retention, Antidiabetic, Canagliflozin Hemihydrate, Sodium Alginate, Optimization.