Determination of histamine by capillary zone electrophoresis with amperometric detection.

Capillary zone electrophoresis was employed for the determination of histamine using end-column amperometric detection with a carbon fiber microelectrode, at a constant potential. The optimum conditions of separation and detection were 10 mmol/L phosphate buffer, pH 5.6 for the buffer solution, 15 kV for the separation voltage, and 1.35 V (versus SCE) for the detection potential. The linear range was from 6.3 x 10(-7) to 1.5 x 1(-5) mol/L with the regression coefficient of 0.9997, and the detection limit was 4.0 x 10(-7) mol/L (S/N = 3). The proposed method was successfully applied to the direct determination of histamine in the beer samples without any sample clean-up procedures.