Hartley R, Cookman J R, Smith I J
J Chromatogr. 1984 Mar 9;306:191-203. doi: 10.1016/s0378-4347(00)80882-8.
A convenient high-performance liquid chromatographic method for the simultaneous determination of caffeine and its N-demethylated metabolites in plasma is described. Separation is achieved by reversed-phase chromatography using a mobile phase consisting of 0.01 M sodium acetate buffer, pH 5.0-methanol-tetrahydrofuran (95:4:1) in conjunction with a mu Bondapak C18 column protected by a guard column containing Bondapak C18/Corasil. With a flow-rate of 3 ml/min, levels in the region of 50 ng/ml for the dimethylxanthines and 100 ng/ml for caffeine can be determined by ultraviolet detection at 254 nm. The method was used clinically for measuring cord blood samples to provide information regarding fetal exposure to caffeine and its N-demethylated metabolites during late pregnancy.
本文描述了一种简便的高效液相色谱法，用于同时测定血浆中咖啡因及其N-去甲基代谢物。采用反相色谱法进行分离，流动相由0.01M醋酸钠缓冲液（pH 5.0）-甲醇-四氢呋喃（95:4:1）组成，结合使用由含Bondapak C18/Corasil的保护柱保护的μ Bondapak C18柱。流速为3 ml/min时，通过在254 nm处进行紫外检测，可测定二甲基黄嘌呤浓度在50 ng/ml左右、咖啡因浓度在100 ng/ml左右的水平。该方法在临床上用于检测脐血样本，以提供关于妊娠晚期胎儿接触咖啡因及其N-去甲基代谢物的信息。
