果汁中9种有机酸的反相高效液相色谱法测定

Simultaneous determination of 9 organic acids in juice beverages by high-performance liquid chromatography

目的：建立HPLC法测定果汁中9种有机酸的检测方法。方法：果汁样品经稀释过滤后，采用Gemini C18色谱柱（4．6mm×250mm，5μm）分离，以0．01mol／L磷酸氢二铵溶液（用磷酸调节pH=2．6）作为流动相，UV210nm检测，外标法定量。结果：9种有机酸的线性范围分别为草酸1．0～400mg／L、酒石酸2．0～500mg／L、丙酮酸1．0～500mg／L、苹果酸5．0～2000mg／L、抗坏血酸1．0～400mg／L、乙酸8．0～2000mg／L、柠檬酸5．0～2000mg／L、富马酸0．5～100mg／L、反乌头酸1．0～400mg／L，各种有机酸的线性相关系数r〉0．999，回收率在93．7％～109．0％，RSD均小于5．0％，最低检测限在0．2～7．5mg／L范围。结论：该方法具有快速、灵敏、简便、准确等优点，可应用于果汁中有机酸的检测，能满足实际工作的需要。

Objective ：To develop an analytical method for the simultaneous determination of nine organic acids in juice be, Jerages by high -performance liquid chromatography （HPLC）. Methods：The juice beverage samples were diluted by water and filtered in the sample vials. Then the nine objects were separated on Gemini C18 column （ 250 mm × 4. 6 mm i. d. , 5 μm） by using a mobile phase of 0. 01 mol/L （ NH4 ） 2 HPO4 （ adjusted pH to 2. 6 by H3PO4 ） at a flow rate of 1.0 ml/min. Detection was performed on an ultraviolet detector at k = 210 nm and quantification was calculated by an external standard method. Results：Calibration curves were linear in the range of 1.0 -400 mg/L for oxalic, acid, 2.0 -500 mg/L for tartaric acid, 1.0 -500 mg/L for pyruvic acid, 5.0 ～ 2000 mg/L for malic acid, 1.0 -400 mg/L for vitamin C, 8.0 -2000 mg/L for acetic acid, 5.0 -2000 mg/L for citric acid, 0. 5 ～ 100 mg/L for fumaric acid and 1.0 - 400 mg/L for trans - aconitic acid, respectively, with a correlation coefficient of more than 0. 999. The limits of detection were found to be 0. 2 - 7. 5 mg/L for the nine analytes. The extraction recoveries were between 93.7% - 109. 0% and the RSD less than 5.0%. Conclusion：This method is simple, rapid, sensitive and accurate for the determination of the nine organic acids in juice beverages and it can be satisfactorily applied to the routine analysis.