以邻苯二甲醛（ＯＰＡ）／３－巯基丙酸（３－ＭＰＡ）为衍生试剂，手动柱前衍生，ＯＤＳ（十八基硅烷）柱分离；以磷酸盐缓冲液（ｐＨ７２）配制流动相，二元一级线性梯度洗脱，紫外３４０ｎｍ检测，在４０ｍｉｎ内分离测定了人和小鼠血浆中２１种游离氨基酸的含量。方法准确可靠，２１种氨基酸保留时间和峰面积的相对标准偏差分别为００９％～０３８％和１５％～４９％（ｎ＝８），氨基酸的进样量为０１～１６ｎｍｏｌ时，峰面积与进样量之间的线性相关系数为０９９６～０９９９，标准加入回收率为９３３％～１０５９％。 (OPA) / 3-mercaptopropionic acid (3-MPA) was used as a derivatization reagent and was separated by manual pre-column derivatization and ODS (octadecylsilane) column. The mobile phase was prepared with phosphate buffer (pH7.2) Phase, binary linear gradient elution, UV 340nm detection, separation of human and mouse plasma in the determination of the content of 21 kinds of free amino acids in mice and mice. The method was accurate and reliable. The relative standard deviations (RSDs) of retention time and peak area of ​​21 amino acids were 009% ~ 038% and 15% ~ 49% (n = 8), respectively.  1 ~ 1  6nmol, the linear correlation coefficient between the peak area and injection volume was 0  996 ~ 0  999, the standard addition recovery was 933% ~ 105  9%.