Simultaneous screening analysis of multiple beta-blockers in urine by gas chromatography-mass spectrometry in selected ion monitoring mode

摘要

A rapid screening procedure is described for the simultaneous determination of 13 beta-blockers in urine at the range of 0.010-1.0 mu gmL~(-1). The procedure involves N-ethoxycarbonyl (EOC) derivatization of p-blockers in urine sample, followed by extraction and further con-version to trimethylsilyl (TMS) derivatives for the analysis by gas chromatography-mass spectrometry (GC-MS) in selected ion monitoring (SIM) mode (GC-SIM-MS). The characteris-tic fragment ions at m/z 260 and m/z 144, and [M -15]~+ ions permitted sensitive and selective detection of most of the p-blockers in the presence of co-extracted urinary amino alcohols at much higher levels. The whole procedure of EOC/TMS derivatization with subsequent GC-SIM-MS analysis was linear (r>= 0.9988). The LODs were varied from 0.03 to 2.7ngmL~(1-). The ranges of precision (%relative standard deviation) and accuracy (%relative error) of the overall procedure at two different added amounts (0.02 and 0.S (mu gmL~(-1)) in urine matrix var-ied from 1.3 to 9.4 and from -9.6 to 9.7, respectively. The recoveries were measured to be ranged from 90.4 to 109.7%.