Determination and identification of amiloride in human urine by high-performance liquid chromatography and gas chromatography-mass spectrometry.
A simple and sensitive high-performance liquid chromatographic method was developed to screen and determine amiloride (I) in human urine. The detection limit of the method is 0.12 micrograms/ml and the recovery of amiloride from urine was 80.4-85.5% at different concentrations. The coefficients of variation were less than 2.8 and 4.4% for intra- and inter-assays, respectively. Total urinary excretion of I in 24 h after oral administration of 5 mg or 15 mg of I ranged from 22.0 to 33.3% of the total dose for three different subjects. I could be detected in urine up to at least 44 h after a 5-mg dose and 72 h after a 15-mg dose. A gas chromatographic-mass spectrometric (GC-MS) confirmatory method was established based on the methanolysis of I to methyl 3,5-diamino-6-chloropyrazine-carboxylate (II). The di-N-trimethylsilyl derivative of II showed very good GC-MS properties and provided reliable structure information for confirmation analysis of I. This is the first time that a reliable GC-MS method has been reported for the detection of urinary I.
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Institut National de la Recherche Scientifique, INRS-Santé, Université du Québec, Pointe-Claire, Canada.
Cooper
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SF
Côté
M G
MG
D000328:Adult; D000584:Amiloride / Q000652:urine*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004952:Esters / Q000378:metabolism; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged
D004952:Esters; D000584:Amiloride