高效液相色谱法测定饮料中咖啡因含量研究

用高效液相色谱法测定饮料中的咖啡因,考察了波长、流动相、柱温、流速等因素对可乐中咖啡因测定的影响。结果表明,饮料中咖啡因含量的最佳测定条件为:波长273 nm,流动相为乙腈∶水=20∶80,柱温为20℃,流速为1 mL/min。在0~15μg/mL的浓度范围内线性关系良好(r=0.999 9);加标平均回收率为99.69%。该方法适合于饮料中咖啡因的含量测定,操作简便、快速、灵敏、准确,可作为饮料中咖啡因的质量控制方法。

Study on Determination of Caffeine Content in Beverage by HPLC

Effects of wavelength,mobile phase,column temperature,flow rate and other factors which affected the determination of caffeine in coke were determined by HPLC.The results showed that the optimum conditions for the caffeine content in the drinks were that the maximum wavelength was 273 nm,the mobile phase of acetonitrile and water was 20∶80,the column temperature was 20 ℃,the flow rate was 1 mL/min.The linear relation of the control was good within the range of 0~15 μg/mL(r=0.999 9).The average recovery rate was 99.69%.The method is suitable for the determination of caffeine content in drinks,and the operation was simple,rapid,sensitive and accurate,and can be used as a quality control way for the caffeine in the drinks.