Abstract: A method was developed to perform the screening, quantification and confirmation of the five β-blockers, propranolol, carteolol, bisoprolol, esmolol, and sotalol, in human urine using gas chromatography-mass spectrometry (GC-MS). In sample preparation, conjugated and unconjugated β-blockers in urine were extracted separately, and the extracts were combined. The extracts were derivatized with N-methyl-N-trimethylsilyl-trifluoroacetamide （MSTFA） and N-methyl-bis(trifluoroacetamide) （MBTFA）. The optimal conditions of GC-MS were established, and the progresses of screening by selected ion monitoring (SIM) mode and confirmation by full scan (SCAN) mode were completed. At last, the quantification curves of the five β-blockers in spiked urine were established by SIM mode. The limits of detection were 0.2-1.0 ng/mL. Overall recoveries were 70.5%-103.4%, and the relative standard deviations were lower than 15%. In addition, the method was successfully applied to the analysis of the positive urine of propranolol, and the urinary excretion curve was also established accordingly. It is significant to prohibit the abuse of β-blockers in doping control.

Key words: doping detection, urine , β-blockers, gas chromatography-mass spectrometry (GC-MS)