Abstract

The aim of the present study is to formulate tenofovir loaded gelatin nanoparticles by using two step desolvation method for targeted release of drug by varying the concentration of polymer and cross-linking agent. The drug, excipients and formulation were separately studied for FT-IR along with other post-formulation studies. Entrapment efficiency for all the formulations was found to be within 67.32 ± 1.24 % to 92.11 ± 1.13 %. Average particle size of different tenofovir loaded gelatin nanoparticle formulations was found to be in the range of 294.9 - 445.3 nm. In-vitro drug release study for glutaraldehyde cross linked gelatin nanoparticles were found to be in between 67.09 % ± 1.423 – 82.41 % ± 1.874 after 8 h of dissolution. The drug release was modified by changing the concentrations of glutaraldehyde and gelatin. Among all the formulation, F5 was considered as the best formulation based on the entrapment efficiency and drug release pattern from nanoparticle core. Kinetics study was performed for all the formulations and best fit model for drug release was determined depending on R2 values. Release kinetics of F5 was found to follow Higuchi mechanism of drug release. HPMC K15M was used as a bioadhesive polymer as well as a gelling agent. Three different gel formulations were prepared by varying concentration of HPMCK15M and incorporated with the best nanoparticle formulation, F5. Membrane permeation and bio-adhesion study revealed F5B gel as an optimum formulation with suitable bioadhesive strength and membrane permeability.

Key words: Tenofovir, gelatin, glutaraldehyde, bioadhesive, HPMCK15M