Simultaneous detection methods for abused diuretics in urine and a quantitative determination method for trichlormethiazide in urine

Abstract

We developed a simultaneous detection method of 9 kinds of diuretics in the urine by using thin-layer chromatographic (TLC) method and/or high-performance liquid chromatographic (HPLC) method. The diuretic drugs were extracted from the urine according to modified Tisdall et al. method by use of 1M phosphate buffer and ethylacetate. The TLC method was performed with a commercially available chromatographic plate containing mixed fluorescent substance and isopropyl alcohol-ammonia mixture as a development solvent. The HPLC method was accomplished with UV detection at 271nm. To examine the limit of detection of the methods, normal subjects were individually administered with commercially available tablets of 11 kinds of diuretics, 9 drugs were detected from 24 h urine of normal subjects. However, 2 drugs were not detected. By applying these methods to urine samples of female patients with hypokalemia, furosemide (FD) and trichlormethiazide (TCT) were detected. The chromatographic peak of FD on HPLC method was further assigned by mass spectrometry. The quantitative determination of TCT in the urine was also developed by HPLC method, and the urine concentration in a patient with self-administration of TCT was 0.80μg/ml.