Rasmussen B B, Brøsen K
Department of Clinical Pharmacology, Odense University, Denmark.
J Chromatogr B Biomed Appl. 1996 Feb 9;676(1):169-74. doi: 10.1016/0378-4347(95)00374-6.
A method for the quantitation of theophylline (13DMX) and the three metabolites, 1-methyluric acid (1MU), 3-methylxanthine (3MX) and 1,3-dimethyluric acid (13DMU) in human plasma and urine has been developed. The method is based on a simple one-step liquid-liquid extraction with ethylacetate-2-propanol followed by isocratic, reversed-phase high-performance liquid chromatography with UV detection (detection wavelength: 273 nm). The overall mean recoveries ranged from 86 to 95% for the four compounds. The detection limit was 1 microM for 1MU, 3MX and 13DMU and 2 microM for 13DMX in urine, and 0.1 microM for 1MU, 3MX and 13DMU and 0.2 microM for 13DMX in plasma. The intra-day and inter-day coefficient of variation was < 6% and < 9%, respectively, and the accuracy was within +/- 10% in both urine and plasma. The simple but sensitive method is highly suitable for the development of theophylline as a probe drug for assessing CYP1A2 activity in man.
已开发出一种用于定量测定人血浆和尿液中茶碱（1,3 - 二甲基黄嘌呤，13DMX）及其三种代谢物1 - 甲基尿酸（1MU）、3 - 甲基黄嘌呤（3MX）和1,3 - 二甲基尿酸（13DMU）的方法。该方法基于用乙酸乙酯 - 2 - 丙醇进行简单的一步液 - 液萃取，然后采用等度反相高效液相色谱法并结合紫外检测（检测波长：273 nm）。这四种化合物的总体平均回收率在86%至95%之间。尿液中1MU、3MX和13DMU的检测限为1 μM，13DMX的检测限为2 μM；血浆中1MU、3MX和13DMU的检测限为0.1 μM，13DMX的检测限为0.2 μM。日内和日间变异系数分别<6%和<9%，尿液和血浆中的准确度均在±10%以内。这种简单但灵敏的方法非常适合将茶碱开发为评估人体中CYP1A2活性的探针药物。
