采用高效阴离子交换色谱及脉冲安培检测法分离并测定了食醋中多种氨基酸。用不同比例的氢氧化钠溶液、乙酸钠溶液及水组成的混合溶液作为淋洗液,以梯度淋洗方式将分离柱上的氨基酸先后洗脱并测定。用提出的方法分析了4种不同品牌的食醋样品,共测得18种氨基酸,此方法毋需柱前或柱后衍生化操作,对18种氨基酸的检出限在1.7-20.0μg·L^-1范围内。根据测定每种氨基酸中所得保留时间值算得的相对标准偏差(n=6)均小于1.2%,作标准加入法测定了各氨基酸的回收率,其值在84%-108%之间。
Amino acids in table vinegar were separated and determined by high performance anion-exchange chromatography with pulse amperometric detector. Gradient elution with mixed eluant, containing sodium hydroxide, sodium acetate and water in different proportions, was used to elute the amino acids from the column, and the amino acids were determined with the pulse amperometric detection. Eighteen amino acids were found in 4 samples of table vinegar of different brand and their contents determined by the proposed method. No pre-column or post-column derivatization was necessary, Detection limits for these amino acids were in the range of 1.7-20. 0 μg · L^-1. Relative standard deviation (n= 6) found from the values of retention time for each of these componental amino acids were all less than 1.2%. Values of recovery obtained by standard addition method were in the range of 84%-108%.