A Liquid Chromatography-Tandem Mass Spectrometry Assay for Quantification of Ethyl Glucuronide and Ethyl Sulfate in Urine

Ethyl glucuronide and ethyl sulfate emerged as the biomarkers of choice for detection of ethanol use as the required sample is urine, enabling easy and noninvasive collection. Further, these biomarkers have a longer detection window in urine than blood ethanol. A liquid chromatography-tandem mass spectrometry method was developed and clinically validated using electrospray ionization in negative mode and selected reaction monitoring. A simple dilution was used for sample preparation on 100 microliters of urine. Gradient elution had a run time of 7 min. The reportable range was established to be 180–100,000 ng/mL for ethyl glucuronide and 50–46,600 ng/mL for ethyl sulfate and between-run imprecision was <7% for both analytes.