Study of uptake kinetics of vincristine for human erythrocytes by capillary zone electrophoresis with electrochemical detection Original Research Article

Capillary zone electrophoresis (CZE) was employed for the determination of vincristine using electrochemical detection with a carbon fiber microdisk bundle electrode at a constant potential of 1.0 V versus saturated calomel electrode (SCE). The optimum conditions of separation and detection are 1.7×10−2 Na2HPO4− 3.2×10−3 mol/l NaH2PO4 (pH 7.5) for the buffer solution, 20 kV for the separation voltage. The limit of detection is 5.0×10−7 mol/l or 2.2 fmol (S/N=3) for the injection voltage of 5 kV and the injection time of 10 s. The recovery of the method is between 95 and 101% for the vincristine taken by human erythrocytes. The method was applied to investigate uptake and accumulation behavior of vincristine for human erythrocytes. The advantages of the method are the small sample volume of CZE and the high selectivity and sensitivity of electrochemical detection.