Formulation and Evaluation of Valsartan Solid Lipid Nanoparticles

Valsartan is a potent and specific competitive angiotensin II antagonist which is used in the management of hypertension. It is well absorbed following oral administration, with rather poor bioavailability of about 25 %. Peak plasma concentration of valsartan occurs 2-4 hours after ingestion. Optimized VAL_SLNS are prepared by hot homogenization method and spray dried to improve handling processing and stability. Solid state studies such as FTIR indicated absence of any chemical interaction between valsartan and the lipid. The mean particles size, Polydispersity index (PDI) and entrapment efficiency of optimized formulation (F-05) was found to be 136.5 nm, 0.424, 80.98% respectively. The drug release study from the nano formulation was studied in Phosphate buffer 6.8 for all the formulations F1 F2 F3 F4 and F5. The results demonstrated that V-SLN formulation (F-5) showed biphasic behaviour with an initial burst release followed by a sustained release maximum up to 72-79% till 12 hours. The release curve was found to follow Korsmeyer Peppas model (R2=0.98). Keywords: hot homogenization, hydrogenated soya phosphatidyl choline, sustained release