高效液相色谱法对白酒中的L-乳酸和D-乳酸的手性分离和测定

Chiral Separation and Determination of L-and D-lactic Acid in Baijiu by High-Performance Liquid Chromatography

运用高效液相法和手性分离柱对白酒中的L-乳酸和D-乳酸进行分离和测定。白酒用超纯水稀释后,经0.22μm滤膜过滤后用配备二极管阵列检测器的高效液相系统检测,检测波长为254nm。检测色谱柱为手性柱Chirex 3126(D)-penicillami(4.6mmi.d×250mmL,5μm),流动相为0.002mol/LCu-SO4溶液(溶剂为5%的异丙醇溶液)。L-乳酸和D-乳酸的标准曲线在0.020~0.800g/L范围线性良好,两者的线性相关系数都为0.999。白酒中L-乳酸和D-乳酸的回收率分别是98.47%~100.75%和100.10%~107.88%。该方法操作简便,精密度和准确度高,适用于白酒中L-乳酸和D-乳酸的测定。

A new method for the separation and determination of L- and D-lactic acid in Baijiu by high-performance liquid chromatography (HPLC) with a chiral colomn had been developed.Baijiu samples were diluted with distilled water,then filtered through 0.22 μm microporous membrane,and analyzed and detected directly by HPLC on chiral columns with a PDA detector at 254 nm. High separation efficiency was achieved by using a Chirex 3126 (D)-penicillami column (4.6 mm i.d×250 mm L,5 μm) and a mobile phase consisting of CuSO4 (2 mmol/L) and isopropyl alcohol-water (5:95).The calibration curves of L- and D-lactic acid were linear with regressions of 0.999 in the concentration range of 0.020 g/L to 0.800 g/L.The average recovery was 98.47 % to 100.75 % for L-lactic acid and 100.10 % to 107.88% for D-lactic acid.The method was simple and easy to operate with high accuracy and reproducibility, and it was suitable for the detection of L- and D-lactic acid in Baijiu.