Abstract
The aim of present investigation was to develop novel oil-in-water (o/w) nanoemulsion based formulation containing atorvastatin for enhancing its oral bioavailability. Solubility of atorvastatin in oil, surfactant and co-surfactant was determined to select the formulation ingredients. Pseudo ternary phase diagrams were constructed by aqueous titration technique and various nanoemulsion formulations were prepared. Formulations taken from o/w nanoemulsion region were subjected to thermodynamic stability and dispersibility tests in order to eliminate metastable formulations in minimum possible time. In vitro drug release was performed by dialysis bag method and compared with the release of drug from suspension and conventional marketed tablet. The optimized formulation showed higher drug release (99.34%), lower droplet size (42.8 +/- 0.42 nm), lower polydispersity (0.237 +/- 0.012), less viscosity (27.51 +/- 1.01 cP) and infinite dilution capability. A pharmacokinetic study was performed after oral administration of atorvastatin at 6 mg/kg in wistar rats. The area under the curve (AUC) and maximum plasma concentration (C-max) in case of atorvastatin nanoemulsion were found 9-fold and 5-fold higher, respectively when compared to simple atorvastatin suspension. The present study illustrated the potential of nanoemulsion dosage form in improving biopharmaceutic performance of atorvastatin.