Abstract
Background and Objective: In the present investigation, we have developed, optimized and evaluated a self-micro emulsifying drug delivery system (SMEDDS) of an anti-hypertensive drug valsartan. The objective of the study was to enhance dissolution rate, solubility and oral bioavailability of valsartan which is BCS-II class drug.
Methods: Saturation solubility studies and emulsification tests were performed for selection of a suitable combination of oil, surfactant and co-surfactant. Pseudo-ternary phase diagram was constructed to estimate microemulsion region for selection of a required range of oil, surfactant and co-surfactant. Doptimal mixture design was utilized to optimize the concentration of various components used in the SMEDDS formulation and to analyze their effect on in vitro percent drug release and globule size. The effect of lipolysis on the rate of drug release from optimized SMEDDS formulation was calculated using in vitro lipolysis model.
Result: The valsartan loaded SMEDDS formulation (F-14) containing 10% Capmul MCM PG 8 (oil), 40% Tween 20 (surfactant) and 50% Transcutol P (co-surfactant) was found to be optimized formulation with smallest globule size of 72.92 nm and significantly superior dissolution rate of valsartan in comparison to the pure drug. No major effect of lipolysis was observed on the diffusion rate of the drug from optimized SMEDDS formulation.
Conclusion: Valsartan loaded SMEDDS formulation was successfully developed by using D-optimal mixture design that could potentially be used for improving the solubility, dissolution rate and bioavailability of Biopharmaceutical Classification System (BCS) class-II drugs.
Keywords: SMEDDS, BCS, bioavailability, lipolysis, in vitro dissolution, D-optimal mixture design, fasted state stimulated intestinal fluids media (FaSSIF).
Graphical Abstract