血液样品用乙腈提取，再以8 000 r·min^-1转速离心10 min，取上清液，经0.22 μm有机滤膜过滤，采用超高效液相色谱-串联质谱法测定滤液中20种常见毒品的含量。以ACQUITY UPLC HSS C₁₈色谱柱为固定相，以不同体积比的乙腈和pH 3.0的5 mmol·L^-1甲酸铵溶液的混合液为流动相进行梯度洗脱，串联质谱分析中采用电喷雾正离子源和多反应监测模式。20种毒品的质量浓度均在10.0~100 μg·L^-1内与其对应的峰面积呈线性关系，检出限（3S/N）为0.10~5.00 μg·L^-1。以空白样品为基体进行加标回收试验，所得回收率为42.3%~113%，测定值的日内相对标准偏差（n=5）为0.050%~15%，日间相对标准偏差（n=3）为2.1%~15%。

The blood sample was extracted with acetonitrile, and then centrifugated for 10 min at the speed of 8 000 r·min^-1. The supernatant was filtered on 0.22 μm organic filtration membrane. UHPLC-MS/MS was applied to the determination of 20 common drugs in the filtrate. ACQUITY UPLC HSS C₁₈ chromatographic column was used as stationary phase, and the mixture of acetonitrile and 5 mmol·L^-1 ammonium formate solution (pH 3.0) mixed in different ratios was used as mobile phase in gradient elution. ESI⁺ and multi-reactions monitor mode were adopted in MS/MS. Linear relationships between values of peak area and mass concentration of the 20 drugs were kept in the same range of 10.0-100 μg·L^-1, with detection limits (3S/N) in the range of 0.10-5.00 μg·L^-1. On the base of blank sample, test for recovery was made by standard addition method; values of recovery found were in the range of 42.3%-113%, with intra-day RSDs (n=5) and inter-day RSDs (n=3) of determined values in the ranges of 0.050%-15% and 2.1%-15%, respectively.