【摘要】 用柱切换高效液相系统直接进样测定人尿中咖啡因的含量，尿样中咖啡因的回收率大于９８％，最低检测浓度可达到０．２ｍｇ／Ｌ。同时与液相提取测定咖啡因的方法进行了比较，结果表明，直接进样法测定咖啡因不仅方法简便，而且减少了提取过程所造成的损失，使定量结果更加准确可靠。更多还原

【Abstract】 A HPLC method with column switching has been developed for detection of caffeine in human urine.The urine sample was directly injected into a precolumn after 3 5min,column switch,the concentrated caffeine was eluted into an analytical column.Caffeine was detected by a diode-array detector at 275nm.The recoveries of the method were above 98%.The relative standard deviation was 0 21%～0 64%.The detection limit was 0 2mg/L.The method is sensitive enough for doping analysis and has been successfully used in the doping control.更多还原