Development and In-Vitro Characterization of Transdermal Delivery Carrier Niosomal Gel of Low Oral Bioavailability Drug Pravastatin Sodium

Abstract

Pravastatin sodium, a widely prescribed HMG-CoA reductase inhibitor, suffers from poor oral bioavailability due to extensive first-pass metabolism and limited intestinal permeability. To overcome these limitations, the present study focuses on the development and in-vitro characterization of a transdermal delivery system in the form of a niosomal gel. Niosomes, non-ionic surfactant-based vesicles, were prepared using the thin-film hydration technique with varying ratios of Span 60 and cholesterol. The optimized niosomal formulations were incorporated into a Carbopol 934 gel base to obtain the final niosomal gel formulations. These formulations were evaluated for physicochemical parameters such as pH, viscosity, spread ability, homogeneity, and drug content, which were found to be within acceptable ranges for topical application. In-vitro drug release studies using Franz diffusion cells demonstrated a sustained release profile over 24 hours. The optimized formulation, G2DPN14, showed the highest cumulative drug release (96.95%), followed by G3DPN14 (81.17%), significantly outperforming the control gel. The release kinetics of G2DPN14 followed Higuchi’s model, indicating a diffusion-controlled mechanism. The enhanced release and stability of the drug within the gel matrix suggest effective encapsulation and prolonged drug delivery potential. Overall, the study confirms that pravastatin sodium-loaded niosomal gel is a promising approach for transdermal drug delivery, offering advantages such as bypassing first-pass metabolism, prolonged release, and improved patient compliance. Future in-vivo and clinical studies are warranted to establish its therapeutic efficacy and safety for the management of hyperlipidaemia and associated cardiovascular conditions.