阴离子交换色谱-积分脉冲安培法测定鱼粉和玉米粉水解液中氨基酸

将高效阴离子交换色谱．积分脉冲安培直接检测法应用于鱼粉和玉米粉水解液中的氨基酸的分析测定。该方法使用Dionex AminoPac PA10阴离子交换柱为分析柱，控制柱温为35℃，以NaOH和NaAc的强碱性溶液为淋洗液，在合适的梯度条件下，可以实现对17种常见氨基酸的高效分离。在强碱性条件下，获得良好分离的各个氨基酸可在配有金工作电极的电化学检测器上以积分脉冲安培法获得高灵敏度的检测。在优化的测定条件下，该方法对这17种氨基酸的检出限在0．21—3．38pmol之间；峰面积校正曲线的线性范围为2—3个数量级；5次平行测定的峰面积的相对标准偏差RSD在0．32％—4．7％之间。该方法应用于玉米粉和鱼粉水解液中氨基酸含量的测定，结果良好。对玉米粉和鱼粉水解液标准加入的回收率分别在81．9％—108．0％和90．0％～108．0％之间。

Determination of Amino Acids in Hydrolysate of Corn Powder and Fish Powder by High Performance Anion Exchange Chromatography with Integrated Pulsed Amperometric Detection

A method for the determination of 17 amino acids in hydrolysate of corn powder and fish powder by high performance anion exchange chromatography with integrated pulsed amperometric detection was established. The chromatographic separation of 17 amino acids was carried out on an Dionex Amino Pac PA10 anion exchange column using a ternary gradient elution. The eluent consists of deionized water, 250 mmol/L sodium hydroxide and 1.0 mol/L sodium acetate, and its flow rate was set at 0.25 mL/min. Under the optimized conditions, 17 amino acids were separated and detected effectively. RSDs of the retention time and peak area for the five determinations of 17 amino acids in hydrolysate of fish powder were no more than 2.8% and 4.7% respectively . The linearities for 17 analytes were two or three orders of magnitude. Detection limits of 0.21~3.4 pmol for 17 amino acids were achieved under the optimized conditions. The accuracy of the proposed method was tested by recovery measurements on spiked samples and good recovery results were obtained.