Reverse phase liquid chromatographic determination of bisacodyl in dosage forms
Valenti, L.P.; Lau-Cam, C.A.
Journal - Association of Official Analytical Chemists 68(3): 529-532
1985
ISSN/ISBN: 0004-5756 PMID: 4019380 Document Number: 247573
Bisacodyl, 4,4'-(2-pyridylmethylene)diphenol diacetate, is a synthetic contact laxative that acts directly on the colonic mucosa to produce normal peristalsis throughout the large intestine. A method is described for the determination of bisacodyl in enteric-coated tablets and suppositories by liquid chromatography (LC). The method will also determine the hydrolysis degradation products monoacetylbisacodyl and desacetylbisacodyl. The sample is dissolved in 2-propanol, and the extract is diluted with the mobile phase and injected into a liquid chromatograph fitted with a .mu.Bondapak C18 column and an UV detector set at 254 nm. The column is eluted with methanol-acetonitrile-0.01 M citric acid (25 + 25 + 50). The pooled mean recovery value for bisacodyl from commercial enteric-coated tablets and suppositories was 99.7% with a pooled coefficient of variation (CV) of 0.72%. For content uniformity assays, the CV were 0.7 and 1.0% for groups of 10 individual commercial suppositories and tablets, respectively. Differences between assay values by the LC and USP XX [United States Pharmacopoeia] methods were 0.2% of declared for enteric-coated tablets (n = 5) and 1.0% of declared for suppositories (n = 2). The LC method can determine as little as 0.015 .mu.g of the monoacetyl or desacetyl degradation product.