Valsartan Loaded Solid Lipid Nanoparticles: Development, Characterization, and In vitro and Ex vivo Evaluation

Valsartan is an antihypertensive drug with poor oral bioavailability ranging from 10-35% because of poor solubility, dissolution and most importantly, extensive first pass hepatic metabolism. The present study deals with the development and characterization of Valsartan-loaded solid lipid nanoparticles (VSLNs) to enhance the solubility, bypass the first pass hepatic metabolism, and enhance the lymphatic absorption leading to improved bioavailability. VSLNs were developed using glyceryl behenate (Compritol 888 ATO) as the lipid and Poloxamer 407 (Pluronic F 127) as the surfactant by the solvent injection method. VSLNs were characterized for mean particle Size (MPS), zeta potential, percentage drug entrapment (PDE), DSC Scans, XRD and TEM analysis. In vitro drug release studies were performed in 0.067 M phosphate buffer of pH 6.8 using dialysis diffusion bag method. Ex vivo drug release studies were also performed for both VSLNs and valsartan suspension in stomach and intestine. The optimized formulation of having the 80 mg lipid, 10 mg drug and 250 mg surfactant was found to have particle size distribution of 142.5 ± 1.859 nm, zeta potential of – 14.3 ± 0.384 mV, and 84.59 ± 0.328% drug entrapment. Based on these results, it is concluded that SLNs show promise for improving the oral bioavailability of valsartan.