SYNTHESIS AND CHARACTERIZATION OF BIODEGRADABLE CLAY- POLYMER NANOCOMPOSITES FOR ORAL SUSTAINED RELEASE OF ANTI INFLAMMATORY DRUG

摘要

In this paper, a clay based drug delivery system comprising of [poly (D, L-lactide-co-glycolide)] (PLGA)/montmorillonite (MMT) nanocomposite has been explored for the oral sustained release of diclofenac sodium (DS) using double emulsion solvent evaporation technique. Encapsulation of diclofenac sodium in PLGA matrix and clay matrix was also undertaken to assess the role of clay and PLGA in drug encapsulation and its subsequent release from the respective formulations. A drug encapsulation efficiency of 98% was obtained for the synthesized PLGA/MMT nanocomposite system. The drug was found to be intercalated in the PLGA/MMT nanocomposite as confirmed by the X-Ray diffraction studies. The thermal analysis shows the crystalline nature of the encapsulated drug in the nanocomposite. The particle size of the drug loaded PLGA/MMT nanocomposite was found to be in the range of 10-20 nm as analysed by high resolution transmission electron microscopic technique (HRTEM). The in vitro drug release studies of the drug encapsulated PLGA/MMT nanocomposite under simulated gastric fluid (phosphate buffer saline, PBS 1.2) shows no drug release while a sustained release was seen under simulated intestinal condition (phosphate buffer saline, PBS 7.4) releasing 51% drug in 8 hours.