Quantitative analysis of tiropramide in human plasma by gas chromatography coupled to mass spectrometry for application to a bioequivalence test

Abstract

Background Tiropramide is used as an antispasmodic agent. A sensitive, selective and simple gas chromatography coupled to mass spectrometry (GC/MS) was developed for quantification of tiropramide in human plasma using internal standard (ISD, (±) α-benzoylamino-4-[2-(dimethylamino) ethoxy]- N, N-dipropylbenzenepropanamide). Methods Tiropramide and ISD were extracted from plasma by solid–liquid extraction and analyzed on a HP-5MS column with mass selective detector. Results The retention times of tiropramide and ISD were approximately 9.8 and 10.2 min, respectively. The calibration curve showed good linearity in the concentration range 5–500 ng/ml ( r 2 = 0.998) for tiropramide in human plasma and showed good precision with CVs between 0.24% and 7.69%, respectively. The method was showed good accuracy with all intra-day ( n = 5) and inter-day ( n = 5) mean concentrations within 87.9–114.1% from nominal. The recovery of tiropramide and ISD were about 75.1% and 71.0% on the average, respectively. This method was successfully applied for the bioequivalence test of 2 formulations of tiropramide in 18 healthy male volunteers who received a single 100 mg dose of each formulation.