Release of indomethacin from bioadhesive tablets containing carbopol 941 modified with Abelmuschus esculentus (okra) gum.

Carbopol 941 (C-941) and Abelmuschus esculentus gum (Okra gum, AEG) were used as bioadhesive polymers in the formulation of mucoadhesive indomethacin tablets. Different batches of the tablet compacts were formulated based on different combination ratios of the polymers. The bioadhesive properties of the tablets were studied using a tensiometer: Tablets coated with 50% w/v solution of Eudragit I. 100 in ethanol, were also prepared and evaluated. The following tablet physical properties were evaluated: hardness, uniformity of weight, disintegration time, friability, and absolute drug content. Release studies were determined in simulated intestinal fluid (SIF pH 7.2) without pancreatin, and in 0.1 N solution of HCl. Result obtained indicated that tablets with equal ratio of C-941 and AEG (1:1) gave the highest bioadhesive strength for both the coated and uncoated tablets. The percentage of drug released ranged from 53-90% for uncoated tablets in 0.1 N HCl and SIF, and 9-16% for coated tablets in 0.1 N HCl, and 63-100% for coated tablets in SIF after 8 hrs.