CORDIA MYXA POLYSACCHARIDE-G-POLY(ACRYLONITRILE) CO-POLYMER BASED MUCOADHESIVE GASTRORETENTIVE DELIVERY OF CAPTOPRIL

The objective of the present study was to prepare gum Cordia myxa-g-polyacrylonitrile using microwave irradiation and to evaluate its mucoadhesive applications. The graft co-polymerization of poly(acrylonitrile) on gum Cordia myxa was carried out employing 3- level 4-factor central composite experimental design. It was observed that the concentrations of ammonium persulphate and concentrations of acrylonitrile exerted a significant synergistic and antagonistic influence on grafting efficiency and percent swelling respectively. Graft co-polymer was characterized by fourier transform infrared spectroscopy, X-ray diffraction and differential scanning calorimeter. Mucoadhesive properties of the graft-copolymer were evaluated by formulating tablets employing captopril as the model drug. On comparative evaluation the gastroretentive tablets of captopril formulated using graft co-polymer (20%) showed ex vivo mucoadhesive time of 12 h whereas the tablets formulated using native Cordia myxa gum and carbopol 934 showed ex vivo mucoadhesive time of 6 h and 8 h respectively. According to the results obtained it was concluded that grafting of poly(acrylonitrile) on gum Cordia myxa enhances its mucoadhesion and thus, the grafted Cordia myxa gum seems to be promising excipient for the development of mucoadhesive drug delivery systems