4种常见药(毒)物GC-MS定性分析的离子丰度比

Ion Abundance Ratios of Qualitative Analysis by GC-MS of 4 Common Drugs(Poisons)

目的探讨气相色谱-质谱(gas chromatography-mass spectrometry,GC-MS)法检测血液中常见药(毒)物特征碎片离子的离子丰度比的最大允许偏差。方法在2个实验室、3种色谱条件下,经液液萃取后,采用GC-MS的全扫描模式对4种常见药(毒)物(敌敌畏、甲拌磷、地西泮和艾司唑仑)进行检测,分析在0.5、1.0、2.0、5.0、10.0μg/mL 5个质量浓度的加标血样的离子丰度比的偏差,同时分析质量浓度为检出限(limit of detection,LOD)、2倍检出限(2LOD)、定量限(limit of quantitation,LOQ)、2倍定量限(2LOQ)时的离子丰度比的假阴性率,利用空白血样分析离子丰度比的假阳性率。结果 2个实验室、4种常见药(毒)物、3种色谱条件下,加标血样离子丰度比偏差的差异无统计学意义(P>0.05)。加标血样的离子丰度比的绝对偏差95%以上在±10%范围内,相对偏差95%以上在±25%范围内。在低浓度(质量浓度<2LOQ)或低信噪比(3~15)情况下,相对偏差大于50%时,假阴性率小于5%,假阳性率为0%。结论建议4种常见药(毒)物加标血样的离子丰度比绝对偏差的判定范围为±10%,相对偏差的判定范围为±25%。

Objective To investigate the maximum allowable deviation of ion abundance ratios of characteristic fragment ions in common drugs(poisons) in blood by gas chromatography-mass spectrometry(GC-MS)method. Methods Four common drugs(poisons)(dichlorvos, phorate, diazepam and estazolam)were detected by GC-MS full scan mode after liquid-liquid extraction in two laboratories and under three chromatographic conditions. The deviations of ion abundance ratios of the four common drugs(poisons) in marked blood samples with concentrations of 0.5, 1.0, 2.0, 5.0 and 10.0 μg/mL were analyzed. At the same time, the false negative rates of ion abundance ratios were analyzed when the mass concentration was limit of detection(LOD), 2 LOD, limit of quantitation(LOQ) and 2 LOQ, and the false positive rates of ion abundance ratios were analyzed with blank blood samples. Results Under the two laboratories, four common drugs(poisons) and three kinds of chromatography conditions, the differences in deviations of the ion abundance ratios of marked blood samples were not statistically significant(P>0.05). More than 95% of the absolute deviations of the ion abundance ratios of the marked blood samples were within the range of ± 10%, and more than 95% of the relative deviations were within the range of ±25%. In cases of low concentration(concentration less than 2 LOQ) or low signal to noise ratio(3-15), the false negative rate was less than 5% and the false positive rate was 0%when the relative deviation was greater than 50%. Conclusion The absolute deviations of ion abundance ratios of four common drugs(poisons) in marked blood samples are advised to have a determination range within ±10%, and the determination range of relative deviations within ±25%.