ROSMARINIC ACID LOADED CHITOSAN NANOPARTICLES FOR WOUND HEALING IN RATS

Drug release properties from dosage forms can be modified by using many rate controlling polymers. Such controlled release properties from carrier systems are desirable since efficient drug delivery is achieved. The aim of the present study was to develop efficient chitosan nanoparticles loaded with rosmarinic acid (RA) and evaluate its drug release properties and wound healing efficiency in rats. Antimicrobial activity and wound healing effect of RA is well established and reported by many workers. Chitosan is also well known for possessing rate controlling properties. For proper application over wounds, the nanoparticles were incorporated into carbopol 940 hydrogel. A fourteen-hour in-vitro release study was carried out to evaluate the drug release efficiency and drug release kinetics of the nanoparticles. Other parameters evaluated were particle size, polydispersity index (PDI), zeta potential, morphology. Carbopol 940 hydrogel was evaluated for optimum viscosity (18.43 +/- 1.7), swelling (250 +/- 7.9) and spreadability (31 +/- 1.5). The in-vivo study was carried out in three groups of animals, those treated with gel containing RA loaded chitosan nanoparticles (RA-NP gel), gel containing only drug (RA gel), and untreated control group. Excision wound model in Wistar rats was used for the investigation of effective healing of wounds. The wound healing efficiency was evaluated by measuring the percentage of wound closure throughout 21 days. Best results were observed in the case of gel containing RA loaded chitosan nanoparticle in comparison with other animal groups.