Electric resistance variation of packing materials in capillary electrochromatography by using fluorinated-bonded silica and octadecylsilane phases

The linear relationship between electric resistance of the packed column fo r capillary electrochromatography and applied voltage was observed in sever al different effluents and packing materials (fluorinated-bonded silica and octahecylsilane). These linear relationships had different slope values wh ich depended on the charges on the surface of the stationary phase. If ther e are the negative charges on the stationary phase during the application o f the electric field, the slope was negative value as observed in the fluor inated-bonded silica packed column. On the other hand, the slope was positi ve value in the fluorinated-bonded silica packed column using 0.1% tetrabut yammonium chloride as an effluent. The inclination of the linear relationsh ip between the electric resistance and applied voltage also depended on the kind of the effluent, the concentration of effluent and the ratio of the o rganic modifier used. In the case of octadecylsilane packed column, the ele ctric resistance of the column did not depend on the applied voltage. The r elationship between the electric resistance and the electroosmotic mobility was also studied.