高效液相色谱法同时测定可乐中苯甲酸、糖精钠、安赛蜜和咖啡因

Simultaneous determination of benzoic acid, sodium saccharin, acesulfame potassium and caffeine in cola soft drink by high performance liquid chromatography

目的建立高效液相色谱同时测定可乐中苯甲酸、糖精钠、安赛蜜和咖啡因的方法,并应用于国际FAPAS能力验证。方法样品经超声脱气用水稀释,采用C_（18）色谱柱分离,以乙酸铵缓冲液（0.02 mol/L）/甲醇为流动相,采用梯度洗脱分离,在230 nm、272 nm波长下进行检测。结果苯甲酸、糖精钠、安赛蜜和咖啡因线性范围为2.0~200μg/m L,线性关系良好,相关系数大于0.999,回收率在97%~103%之间,RSD为0.5%~2.8%之间,检出限在0.005~0.02μg/m L之间。结论该法灵敏度高、重现性好,用于FAPAS能力验证时结果接近中值。

Objective To establish a methodfor the simultaneous determination of benzoic acid, sodium saccharin, acesulfame potassium and caffeine in cola by high performance liquid chromatography（HPLC）, and apply to international FAPAS proficiency testing. Methods After ultrasonic degasification, the samples were diluted by water, separated on a C_（18） column with the mobile phase of ammonium acetate（0.02 mol/L）/methanol in gradient elution, and detected at the wavelength of 230 nm and 272 nm. Results The calibration curves within the range of 2.0~200 μg/m L showed a good linearity and the correlation coefficients were higher than 0.999. The individual average recovery at 3 spiked concentration levels ranged from 97% to 103%, while the relative standard deviations（RSD） were between 0.5%~2.8%（n=6）. The limits of detection of benzoic acid, sodium saccharin, acesulfame potassium and caffeine were 0.005~0.02 μg/m L. Conclusion Theestablished method is sensitive and accurate and can be used to the FAPAS proficiency testing, and the Z-scores of the benzoic acid, saccharin, acesulfame potassium and caffeine were close to median.