Identification and quantification of acidosis inducing metabolites in cases of alcohols intoxication by GC–MS for emergency toxicology

Abstract

A simple, cost effective, and fast gas chromatography method with mass spectrometry detection (GC–MS) for simultaneous measurement of formic acid, glycolic acid, methoxyacetic acid, ethoxyacetic acid and 2-hydroxyethoxyacetic acid in serum and urine was developed and validated. This multi-analyte method is highly suitable for clinical and emergency toxicology laboratory diagnostic, allowing identification and quantification of five most common acidosis inducing organic acids present in cases of alcohol intoxication. Furthermore, when patients are admitted to emergency unit at late stage of toxic alcohol intoxication, the concentration of parent compound may be already low or not detectable. This new method employs a relatively less used class of derivatization agents – alkyl chloroformates, allowing the efficient and rapid derivatization of carboxylic acids within seconds. The entire sample preparation procedure is completed within 5min. The optimal conditions of derivatization procedure have been found using chemometric approach (design of experiment). The calibration dependence of the method was proved to be quadratic in the range of 25–3000mgL−1, with adequate accuracy (97.3–108.0%) and precision (<12.8%). The method was successfully applied for identification and quantification of the selected compounds in serum of patients from emergency units.