咖啡因代谢物AFMU,1X的测定及其在N-乙酰化分型中的应用

 目的：建立一套测定咖啡因的2种主要代谢物AFMU和1X的高效液相色谱（HPLC）方法。方法：选用岛津Shim-Pack CLC-ODS柱，流动相为甲醇-乙腈-水-醋酸（12∶1．5∶86．45∶0．05）。对120名健康志愿者服用咖啡5g后4h～5h尿样进行测定，以AFMU与1X摩尔比作为代谢指标，并作频谱显示。结果：受试者可明显划分为快乙酰化者和慢乙酰化者，快、慢乙酰化表型之比101∶19。结论：咖啡因HPLC方法的建立及在N-乙酰化分型中的成功应用，为国内进行N-乙酰化分型提供了一种值得推广的新方法。

Determination of caffeine metabolites of AFMU, 1X and their application in N acetyltransferase phenotyping

OBJECTIVE: To establish a high-performance liquid chromatographic (HPLC) method for determining two major metabolites of caffeine, 5-acetylamino-6-formylamino-3-methyluracil (AFMU) and 1-methylxanthine (1X). METHOD: A Shim-Pack CLC-ODS column was used, and the mobile phase consisted of methyl alcohol-acetonirile-water-acetic acid (12∶1.5∶86.45∶0.05). Each of 120 volunteers provided a spot sample of urine between 4 and 5 hours after taking 5 g coffee, and the molar ratio of AFMU to 1X was determined. RESULTS: The molar ratio of AFMU to 1X afforded segregation of two apparent modes of acetylation capacity.-Nineteen slow acetylators were found among 120 volunteers. CONCLUSION: The established HPLC method for determining the AFMU, 1X is stable and can be used in segregation of phenotype of N-aceyltransferase.