β-Hydroxyethoxyessigsäure (HEAA) in Urin [Biomonitoring Methods in German Language, 2015]

β-Hydroxyethoxyacetic acid (HEAA) in urine The documentation presents the selective detection of β-hydroxyethoxyacetic acid (HEAA), which is considered to be the main metabolite of 1,4-dioxane and diethylene glycol, respectively. The urine sample to be analyzed is diluted with purified water and, after addition of the deuterated internal standard (D4-HEAA), acidified with concentrated hydrochloric acid and then extracted with ethyl acetate. An aliquot of the ethyl acetate phase is evaporated to dryness under a stream of nitrogen. The residue is derivatized by addition of N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) and the bis-silylated β-hydroxyethoxyacetic acid is analyzed after electron impact ionization using GC–MS in the Selected Ion Monitoring (SIM) mode. Keywords: β-Hydroxyethoxyessigsaure; HEAA; Diethylenglycol; 2-Hydroxyethoxyessigsaure; Urin; Biomonitoring; 1,4-Dioxan; GC-MS; GC-HR-MS; Biologisches Monitoring