积分脉冲安培检测-离子色谱法同时测定果汁中20种氨基酸

Simultaneous determination of twenty amino acids in fruit juice by ion chromatography with integrated pulsed amperometric detection

建立了梯度淋洗-积分脉冲安培检测-离子色谱法测定果汁中20种氨基酸的方法,通过对流速、色谱柱温度、pH等实验影响因素的考察,探索出了适合20种组分测定的多级梯度淋洗条件。结果表明,当流速为0.25mL/min,pH在5.5~7.0,柱温为30℃时,20种组分在0.05~2.50mg/L浓度范围内具有良好的线性关系(R>0.995)。除了亮氨酸、异亮氨酸、色氨酸外,其他17种组分检出限均小于0.05mg/L;在0.20、0.50、2.00mg/L三个添加浓度下,回收率为82.73%~107.39%,RSD在1.97%~8.72%范围内。

A method of gradient elution ion chromatography with integrated pulsed amperometric detection for simultaneous determination of twenty amino acids in fruit juice was established,the effects of flow rate,column temperature,pH value of solution were studied to find out the most suitable gradient elution conditions.The results show that the best conditions are:flow rate 0.25 mL/min,pH value 5.5~7.0,column temperature 30℃.Under the above conditions,the linear relation among twenty components are good in the range of 0.05-2.50 mg/L and the linear correlation coefficient are all above 0.995.The limits of detection(S/N=3)of other components are less than 0.05 mg/L except leucine,isoleucine and tryptophan.The recoveries of twenty amino acids in fruit juice are 82.73%-107.39%at the concentration of 0.20、0.50、2.00 mg/L,and the relative standard deviations(RSDs)are in the range of 1.97%~8.72%.