高效液相色谱法测定食品中的叶酸

在食品样品中加入体积分数 60 %高氯酸溶液去蛋白 ,过滤后进样检测叶酸。流动相选用pH 3 .5 ,体积分数 12 %的乙腈 ,浓度 5 0mmol/L的KH2 PO4溶液。流速为 1mL/min ,经ODSC 18柱分离 (柱温为 40℃ ) ,用质量分数 0 .5 %的过二硫酸钾溶液作柱后衍生剂 ,流速为 0 .3mL/min ,柱后反应温度为 60℃ ,经荧光检测器 (Ex :3 65nm ,Em :45 0nm)检测定量。实验结果表明 ,在 0 0 1～3 2 μg/mL的浓度范围内 ,线性良好 ,相关系数为 0 .9999;最低检出浓度为 0 .0 1μg/mL ;方法回收率为 98.1% ;变异系数为 2 3 %。

Measurement of Folic Acid in Food Using HPLC

perchloric aicd was added into food sample to remove protein. After filtering the sample, the filtrate was injected into HPLC to measure its folic acid. 50mmol/L potassium dihydrogen phosphate containing 12% acetonitrile (v/v), pH 3.5 was used as mobile phase, the flow rate was 1mL/min. ODS C18 was used as separating column, column temperature was 40℃. Potassium persulfate was chosen as postcolumn derivative agent, the flow rate was 0.3 mL/min, reaction temperature was 60℃. The folic acid derivate was measured with fluorescence detector (Ex:365nm, Em: 450nm). It is seen that the standard curve was linear with the range of 0.01～3.2μm/mL, its related coefficient was 0.9999. The determination limit of this method was 0.01ng/mL, the yield was 98.1% and the variation coefficient was 2.3%.