Formulation, in vitro and in vivo evaluation of celecoxib nanosponge hydrogels for topical application

Background: Celecoxib is an extremely lipophilic and poorly water soluble NSAID which has gastrointestinal side effects when used chronically. Solubility of celcoxib is 7.6 mu g/ml and therefore the oral bioavailability of celecoxib is 40% when administered as a capsule dosage form. Objective: The purpose of this current study is to improve the solubility of Celecoxib using beta-cyclodextrin and NN-methylene bisacrylamide Nanosponge hydrogel formulation. Methods: Nanosponges of celecoxib were prepared and characterized by differential scanning colorimetry, X-ray diffractometry, FT-IR analysis and evaluated by Zeta-potential and Polydispersity index and drug entrapment efficiency. Further, celecoxib nanosponges were dispersed in 1% carbopol 934 hydrogel and the gel was evaluated for its viscosity, pH, spreadability, in vitro diffusion. In vivo, pharmacokinetic and skin irritation studies conducted using rats. Results: Solubility of freeze dried nanosponge particles were in the range of 230.49 +/- 0.16 490.48 +/- 0.88 mu g/ml, which indicates 30 to 65 fold increases in the solubility compared to pure drug. Conclusion: These results confirm that nanosponge formulation is ideal for increasing the solubility and bioavailability of poorly water soluble drug like celecoxib. (C) 2017 Elsevier B.V. All rights reserved.