Emulsion droplet coalescence

The goal of the present investigation was to formulate and evaluate chitosan and Eudragit Nanoparticles of Stavudine for antiviral therapy. Nanoparticles of Stavudine were prepared using chitosan, Eudragit S 100, liquid paraffin and Tween-20 using Emulsion droplet coalescence method. The concentration of the polymers Chitosan and Eudragit S 100 were selected based on the results on preliminary screening. The nanoparticles prepared were evaluated for morphology, loading efficiency and in-vitro release. The particle shape and morphology of the prepared Stavudine nanoparticles were determined by SEM analysis. The amount of Stavudine entrapment in the nanoparticles was calculated by the difference between the total amount of drug added to the nanoparticle and the amount of non-entrapped drug remaining in the aqueous supernatant. A Franz diffusion cell was used to monitor Stavudine release from the nanoparticles. The formulations CF1, CF2, EF2 and EF3 showed good drug release from the polymer. The percentage cumulative drug release after 12 hours was 75.54, 75.89, 78.86 and 76.42% respectively. However about 15% initial burst release was found at 1 hour in all formulations. EF2 released 78.86% of Stavudine 12 hours with a burst drug release nearly 14.86% of drug within the initial 1 hour. Formulations 4 out of 8showed good drug release from the polymer, the percentage cumulative drug release after 12 hours were in the range of 72-78 %. Among the four formulations EF 2 (1% Chitosan & 1.5 % EudragitS 100) showed maximum drug release in 12 hours diffusion study and good entrapment efficiency. In-vitro antiviral study revealed thatthe formulated nanoparticles were found to have good viral activity on viral cells in sustained manner.