Abstract

Rheumatoid arthritis (RA) is a systemic autoimmune inflammatory disease that affects the multiple joints of the body in a symmetric pattern. Presently various drugs present are usually given by either the oral route or the IV route. This causes many side effects since the drug is being distributed throughout the body. In this research work, the nano lipid vesicles of a novel drug camptothecin are being used which is targeted directly into the synovial cavity by means of a targeting ligand. The nano lipid vesicles were prepared by the ether injection method. Once the nano lipid vesicles were prepared, they were coated with a biomarker hyaluronic acid (HA). Ha was used as a ligand to coat the vesicles, so that it would increase the retention time in vivo. Folic acid is a high affinity ligand for the Folate receptor (FR). It has various features which makes it an attractive ligand for drug targeting. Folate ligand is also small in size which allows good tissue penetration and rapid clearance from the receptor negative tissues. Hence folic acid was also coated on the surface of the nano lipid vesicles to increase its affinity with the receptors present on the surface of the synovial cavity. This increased the entrapment efficiency and the drug release. The nano lipid vesicles were characterized for particle size, zeta potential and in vitro drug release studies. The in vitro drug release studies were carried out in phosphate buffer pH 7.4 and simulated synovial fluid. We wanted to study the nature of drug release in the synovial fluid, hence to mimic the synovial fluid, the simulated synovial studies were conducted. The nano lipid vesicles showed a sustained and a prolonged release upto 72hrs in the simulated synovial fluid. Further the studies were also carried out in vivo in Lewis Wister Rats, Which has proved the formulation to retain within the synovial cavity and decrease the inflammation within 72hrs.