高效液相色谱-蒸发光散射检测法直接检测20种未衍生基本氨基酸

摘要

An analytical method for the determination of underivatized amino acids was established with high performance liquid chromatography (HPLC) coupled with evaporative light-scattering detection (ELSD). A domestic evaporative light-scattering detector was used to determine underivatized amino acids. A BISCHOFF? C18 AQ PLUS column and a solvent gradient elution with 0. 2% heptafluorobutyric acid containing 0. 1 % trifluoroacetic acid as mobile phase A and methanol as mobile phase B were used. The temperature of the drift tube in ELSD was 40 t and the flow rate of dry air was 2. 5 L/min. The logarithm of the peak area and logarithm of the mass of each separated amino acid was in good linearity. The linear ranges of the 20 amino acids were from 30 - 300 mg/L. The limits of detection (S/N > 3) for the underivatized amino acids were from 24 ng to 100 ng. The average recoveries of the 20 amino acids were between 90. 6% and 106. 0%. This method and system are simple, rapid and accurate for the determination of underivatized amino acids. It can be used for the determination of underivatized amino acids in pharmaceutical, food and chemical industry fields.%应用国产蒸发光散射检测器( ELSD),建立了一种采用反相高效液相色谱-蒸发光散射检测器(RHPLC-ELSD)直接测定20种未衍生基本氨基酸的分析方法,并将其用于氨基酸注射液中氨基酸含量的测定.采用BISCHOFFTM C18 AQ PLUS色谱柱(250mm×4.6mm,5μm)分离,以甲醇-0.2％七氟丁酸溶液(含0.1％三氟乙酸)为流动相进行梯度洗脱,流速0.8 mL/min,ELSD飘移管温度40℃,载气流量2.5 L/min,对20种基本氨基酸进行分离检测.氨基酸的质量浓度在30～300 mg/L范围内,其峰面积的对数值与进样质量的对数值呈良好的线性关系；氨基酸的检出限(信噪比(S/N)＞3)介于24～100 ng之间,样品加标回收率为90.6％ ～ 106.0％.结果表明,该系统及方法操作简便快速、准确可靠,无需依靠专门的氨基酸分析仪或衍生处理氨基酸即可直接测定氨基酸注射液中氨基酸含量,为药品、食品及化工生产等领域混合氨基酸样品的直接检测提供了参考.