Confirmation analysis of ethyl glucuronide and ethyl sulfate in human serum and urine by CZE‐ESI‐MSⁿ after intake of alcoholic beverages

Abstract

CZE coupled to sheath liquid-based electrospray ionization (ESI) and multiple-stage ion trap mass spectrometry (MS(n) ) was used for the confirmation analysis of ethyl glucuronide (EtG) and ethyl sulfate (EtS) in human serum and urine collected after intake of alcoholic beverages. Electrophoretic separations were performed in uncoated fused-silica capillaries using a pH 9.5 ammonium acetate background electrolyte and normal polarity. MS detection of EtG and EtS occurred after negative ionization using a spray liquid containing 0.5% v/v ammonia in isopropanol/water (60:40%, v/v). CZE-MS and CZE-MS² results obtained after injection of solid-phase extracts for EtG and EtS and of diluted urine confirmed the presence of EtG and EtS in samples whose levels were previously determined by CZE with indirect UV detection. Detection limits of each compound were estimated to be around 2.0 (injection of diluted urine) and 0.2 μg/mL (extracts).

Sensitive determination of ethyl glucuronide in serum and whole blood: detection time after alcohol exposure compared with urine

“…In traffic medicine, EtG can be used as an indicator of hangover [12] and in post-mortem investigations as a valuable complement to ethanol measurement [13]. In the present study, a method for measuring EtG in serum and whole-blood samples with more than 10-fold improved sensitivity [15][16][17][18][19][20][21][22] was successfully developed. The method is based on a simple sample preparation procedure that easily can be automated.…”

“…EtG has been measured in whole-blood and serum specimens by methods based on gas chromatography (GC) and liquid chromatography (LC) combined with MS, and by capillary electrophoresis [15][16][17][18][19][20][21][22], using solid-phase extraction or protein precipitation for sample preparation. Currently, LC-MS is mainly used as it allows EtG to be analyzed in its native form [16].…”

Ethyl glucuronide

“…A comparison of five LC-MS methods for measurement of urinary EtG and EtS recommended that solid-phase extraction followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) be adopted as the reference method as it had the best selectivity and sensitivity. 41 Other methods developed include reversed-phase liquid chromatography with pulsed electrochemical detection, 42 microwave-assisted extraction followed by gas chromatography-mass spectrometry (GC-MS), 43,44 GC-MS with solidphase extraction for sweat samples 45 and GC-MS of silylated derivatives, 46 capillary electrophoresis, 47 capillary zone electrophoresis-mass spectrometry, 48 capillary isotachophoresis and zone electrophoresis 49 and an enzyme-linked immunosorbent assay based on polyclonal antibodies. 50 Recently, a commercially available enzyme immunoassay (EIA) method based on a new monoclonal antibody (DRI Ethyl Glucuronide Enzyme Immunoassay; Thermo Fisher Scientific Diagnostics, Hemel Hempstead, UK) came onto the market for the analysis of EtG in urine.…”

CE-MS in Forensic Sciences with Focus on Forensic Toxicology

“…Caslavska et al used CZE-ESI-ion trap MS n after negative ionization for the analysis of EtG and EtS in human serum and urine [114]. reach the detector within a reasonable time, an additional cathodic buffer flow generated via application of constant pressure of 5 mbar at the anodic side was used.…”