采用高效毛细管电泳一非接触电导检测法,使用未涂层石英毛细管(50μmi.d.×45cm,Leff=40cm),以3.2mmol/L氢氧化钠+0.4mmol/L柠檬酸+2.5mmol/L乙酸铜+5.0mmol/L L-精氨酸+15.0mg/L羟丙基甲基纤维素为电泳运行液,实现了未衍生化的D,L-丝氨酸对映体的基线分离和检测.其线性范围为0.35~30mg/L,检出限(S/N=3)为0.10mg/L.对影响分离度的因素如手性选择剂、电泳运行液的组成和浓度、分离电压和进样方式等进行了探讨.结果表明,该方法无需衍生化预处理,高效低耗,可实现常见氨基酸共存组分的不干扰测定,能有效测定小鼠脑组织样品中的D-丝氨酸含量.
A new method for enantioseparation of underivatized D,L-serine in biological matrices by capillary electrophoresis with contactless conductivity detection using binary chiral selectors (Cu-L-Arg and HPMC) was developed. The enantiomers of D,L-serine could reach an excellent baseline separation in an uncoated fused- silica capillary (50 μmi.d.×45cm, Leff = 40 cm) under the chosen separation conditions and using 3.2 mmol/L NaOH+0. 4 mmol/L Cit+2. 5 mmol/L Cu(Ac)2+5.0 mmol/L L-Arg +15.0 mg/L HPMC(pH=9.8) as the running buffer. The calibration curve of the enantiomers showed good linearity in the range of 0. 35--30 mg/L with a limit of detection (LOD) of 0. 10 mg/L. Effects of several factors on resolutions, such as the composition of the running buffer, pH, separation voltage and injection method were investigated to acquire the optimum conditions. The proposed method, without derivatization, has been applied to determine the D-serine contents in rat brain tissue, and was demonstrated simple, efficient, cost-effective and reproducible.