Determination of nitroglycerin and its dinitrate metabolites in urine by gas chromatography–mass spectrometry as potential biomarkers for occupational exposure

This paper describes a method for the quantitative analysis of nitroglycerin and its dinitrate metabolites (1,2- and 1,3-glycerol dinitrate) in urine. After liquid–liquid extraction the analytes were separated and quantified using gas chromatography–mass spectrometry with negative ion chemical ionisation. The method can detect above 0.3 nmol/l for all analytes and is linear over the range of at least 0–44 nmol/l. The method was then used to determine metabolite levels in a subject using nitroglycerin therapeutically for the treatment of angina. Metabolites were stable in urine for at least 6 days at room temperature, ∼4°C and −20°C.