FLOATING IN SITU RAFT FORMING LIQUID GASTRORETENTIVE DRUG DELIVERY SYSTEM CONTAINING POORLY WATER-SOLUBLE DRUG

Abstract

Present work was aimed to develop a liquid in situ raft forming floating gastroretentive system of repaglinide using gellan gum, pectin, and sodium alginate. The formulations were characterized in terms of compatibility of drug-excipient by Fourier transform infrared, drug content, effect of processing parameters on physical form of drug (crystalline or amorphous) by X-ray diffraction analysis, thermal behaviour by differential scanning calorimetry, and in vitro drug release study. The results confirm no interaction between the drug-excipients and fusion of drug crystals within the polymer matrix in amorphous form. The gel raft-floated for more than 24 h. All the formulations showed instantaneous gelation within 30 seconds in 0.1N HCl (pH 1.2). Formulation containing gellan gum (500 mg), pectin (500 mg), and glycerol monostearate (500 mg) released 21% of the drug in first 4 h, 69% in 6 h and reached 97% in 7 h. Without gellan gum, 35% of the drug was released in the first 2 h and reached 90% in 4 h. Based on these results it is suggested that the incorporation of drug into the liquid in situ raft forming floating system may be an appropriate strategy to improve the dissolution profile of poorly soluble drugs.