Nanocarriers as Promising Novel Systems for Controlled Delivery of Diclofenac Sodium

The formulation and evaluation of diclofenac sodium from liposomes, niosomes and nanoemulsion are analyzed. The release profiles of diclofenac sodium were almost similar in all the formulations. It is found that 85% of diclofenac sodium diffused out from the colloidal systems within 8hrs and practically all the drug was released within 12hrs. In addition to this controlled release, the similarity of the release profiles obtained for liposomes, niosomes and nanoemulsion signifies that the internal structure has little role in the release process. The drug released fast and completely from the carriers upon high dilution, but it is slowed down a little when they are not diluted. The maximium amount of diclofenac sodium was released from nano emulsion as well as liposomes after 12 hrs at 1 in 200 dilution where as in niosomes, it was found at 1 in 100 dilution. But surprisingly, the release was decreased upon further dilution. The higher the surfactant content, the higher the globule size of the nanoemulsion. The mean size of the systems was decreased upon increasing dilution. Among all the systems, the mean size of niosomes was decreased upon increasing the dilution up to 1:200. It was finally depicted that the dilution effect on the zeta potential of the systems shifted from negative to positive by adding polysorbate 80. The zeta potential of all the systems was significantly good indicating stable systems.