Eect of injection time
Injection time determining the amount of sampling
aects both the peak current and peak shape. The eect
of injection time on CE separation was investigated by
changing the sampling time from 2 to 16 s at injection
voltage of 20 kV. As shown in Fig. 2, peak current
increases with increasing sampling time, and the peak
width of the analyte increases simultaneously. When the
injection time is longer than 10 s, the peak current levels
o and the peak broadening becomes more severe. In
this experiment, injection time of 10 s at 20 kV is selected. At the optimum conditions, the typical electropherogram for lactose standard is shown in Fig. 3B, and
the lactose peak appears at 20 min.