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

Objective To establish a method for determination of glutamine in serum by capillary zone electrophoresis/end-column 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 2.00×10-2 mol/l 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× 10-6 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 electrophoretic peak current.Conclusion Above method is efficient,sensitive and accurate.It can be applied to the determination of glutamine in human serum.