毛细管电泳/柱端安培检测血清中谷氨酰胺

Determination of glutamine in serum by capillary electrophoresis with end-column amperometric detection

目的建立毛细管区带电泳/柱端安培检测血清中谷氨酰胺的方法。方法通过研究谷氨酰胺柱前衍生化反应条件以及缓冲液pH值、缓冲液浓度、分离电压和检测电势对分离检测谷氨酰胺衍生产物的影响,确定了最佳实验条件。结果毛细管电泳/柱端安培检测谷氨酰胺的最佳条件是:衍生反应时间为30min,缓冲液为2.00×10-2mol/LNa2B4O7-8.57×10-3mol/L NaOH(pH=9.7),分离电压为20kV,检测电势为1.10V。谷氨酰胺的检测限为1.0×10-6mol/L即1.08fmol(S/N=3),线性范围为1.0×10-6mol/L～1.0×10-4mol/L,迁移时间及峰电流的相对标准偏差分别为2.2%、3.1%。结论所建立的毛细管电泳/柱端安培检测法灵敏、快速、准确,适用于血清样品中谷氨酰胺的测定。

Objective To establish a method for determination of glutamine in serum by capillary zone electrophoresis/end-eolumn amperometric detection. Method The conditions including pH, the buffer concentration, the separation voltage and detection potential for separation and detection of derivative of glutamine with NDA and CN-in Na2B4O7-NaOH buffer have been studied. Result The optimum conditions of separation and detection are 2.00×10-2mol/1 Na2B4O7-8.57×10-3 mol/L NaOH（pH=9.7） for the buffer solution, 20 kV for the separation voltage, and 1.10 V versus saturated calomel electrode for the detection potential, respectively. The limit of detection is 1.0×104 mol/L or 1.08 fmol （S/N=3）. The linear range of the calibration curve is 1.0×10-6 mol/L-1.0×10-4 mol/L. The relative standard deviation is 2.2% for the migration time and 3.1% for the electrophorefic peak current. Conclusion Above method is efficient, sensitive and accurate. It can be applied to the determination of glutamine in human serum.