Jarman M, Gilby E D, Foster A B, Bondy P K
Clin Chim Acta. 1975 Jan 6;58(1):61-9. doi: 10.1016/0009-8981(75)90485-4.
The levels of cyclophosphamide in the blood and the urine of patients have been monitored by direct insertion, electron impact mass spectrometry using the principle of stable isotope dilution. When a tetradeuterated analogue of the drug was added to a sample of blood or urine the concentration of cyclophosphamide could be determined from the ratio of the intensities of the signals (M-CH2 C1) characteristic for cyclophosphamide and the tetradeuterated analogue present in the mass spectrum of a chloroform extract. The procedure is highly specific for cyclophosphamide and obviates the need to use radioactively labelled cyclophosphamide for quantitation of the drug in man.
采用稳定同位素稀释原理，通过直接进样、电子轰击质谱法对患者血液和尿液中环磷酰胺的含量进行了监测。当向血液或尿液样本中加入该药物的四氘代类似物时，可根据氯仿提取物质谱中代表环磷酰胺及其四氘代类似物的信号（M-CH2 C1）强度比来测定环磷酰胺的浓度。该方法对环磷酰胺具有高度特异性，无需使用放射性标记的环磷酰胺来定量人体中的药物。
