Simultaneous determination of atenolol and furosemide in intestinal perfusion samples by validated reversed-phase high-performance liquid chromatography

A reversed-phase high-performance liquid chromatographic method was developed for quantification of atenolol and furosemide in intestinal perfusion samples to assess possible drugdrug interaction during pre-absorption stage. The method utilized a simpler mobile phase [acetonitrile:50 mM pH 6.5 phosphate buffer (20:80 v/v)] than those reported previously for these drugs, with added advantage of their UV detection (I»=276 nm). The analytical method passed the validation tests recommended by ICH and United States Pharrnacopeia. The method was specific for both the drugs, and able to resolve the drug peaks with no interference from components of intestinal perfusate. The method was accurate, precise and linear within the desired range. This method can be successfully employed for quantitative analysis of atenolol and furosemide, alone or in combination.