In Vitro Drug Release Study of Bisacodyl Enteric-Coated Tablet in Various Artificial Dissolution Media

This study investigates the in vitro dissolution profiles of bisacodyl from enteric-coated tablets in various colon-simulated media. The aim was to compare the effectiveness of different media in mimicking the conditions of the human colon and predicting drug-release behavior. Genuine phosphate buffer pH 7.4 (phosphate buffer), rat cecal-containing phosphate buffer pH 7.4 (rat cecal), lactase-containing phosphate buffer pH 7.4 (lactase), probiotics-containing phosphate buffer pH 7.4 (probiotics), and probiotics & lactase-containing phosphate buffer pH 7.4 (probiotics-lactase) were used as the colon simulation media. The experiment was carried out sequentially in a modified type I dissolution test apparatus for 12 hours including 2 hours in HCl pH 0.1 M, 3 hours in phosphate buffer pH 6.8, and 7 hours on colon simulation media. Furthermore, the sample aliquots were analyzed using UV-Vis spectrophotometer. The results demonstrated that the fastest and highest drug release occurred in the probiotics-lactase media, with 110.63% bisacodyl released after 12 hours, followed by probiotics-only media (92.83%), rat cecal media (85.83%), and lactase media (70.59%). The lowest release was observed in phosphate buffer pH 7.4 (42.09%). Drug-release profiles among various dissolution media showed significant differences, with p-values < 0.05. It was concluded that pH, microbial activity, and enzyme content significantly influenced the release profile of bisacodyl from enteric-coated tablets.