Bondesson U, Hartvig P, Abrahamsson L, Ahnfelt N O
Biomed Mass Spectrom. 1983 Apr;10(4):283-6. doi: 10.1002/bms.1200100410.
An analytical procedure has been developed for the simultaneous determination of ketobemidone and its N-demethylated metabolite, norketobemidone. After isolation from plasma and re-extraction to acidic aqueous phase, the two aminophenols were extracted as ions pairs with tetrabutylammonium to dichloromethane, where derivatization with ethyl chloroformate took place. Determination was performed by gas chromatography mass spectrometry with selected ion monitoring. Ketobemidone and norketobemidone could be detected in plasma in a concentration of 1 ng ml-1 and 3 ng ml-1, respectively. Determinations were performed down to 5 ng ml-1. The relative standard deviation of the method in the analysis of 10 ng ml-1 of ketobemidone and norketobemidone, respectively, was 8% and 9% (n=10). The absolute recovery of unconjugated ketobemidone and norketobemidone through the method at the 100 ng ml-1 level was 91% and 85%, respectively. The method was applied to the determination of ketobemidone and norketobemidone in plasma from patients given ketobemidone. The concentrations of unconjugated norketobemidone was too small to be detected.
已开发出一种分析方法，用于同时测定凯托米酮及其N - 去甲基代谢物去甲凯托米酮。从血浆中分离并重新萃取到酸性水相后，这两种氨基酚与四丁基铵形成离子对，萃取至二氯甲烷中，在二氯甲烷中用氯甲酸乙酯进行衍生化。采用气相色谱 - 质谱联用仪，通过选择离子监测进行测定。在血浆中可分别检测到浓度为1 ng/ml的凯托米酮和3 ng/ml的去甲凯托米酮。测定下限为5 ng/ml。该方法对10 ng/ml的凯托米酮和去甲凯托米酮进行分析时，相对标准偏差分别为8%和9%（n = 10）。在100 ng/ml水平下，通过该方法未结合凯托米酮和去甲凯托米酮的绝对回收率分别为91%和85%。该方法应用于测定服用凯托米酮患者血浆中的凯托米酮和去甲凯托米酮。未结合去甲凯托米酮的浓度太小，无法检测到。
