On-line concentration and separation of cationic and anionic neurochemicals by capillary electrophoresis with UV absorption detection

► We present a CE method for the analysis of cationic and anionic neurochemicals. ► Stacking and separation of 12 neurochemicals was achieved using PEO and glycerol. ► The limit of detection for twelve neurochemicals ranged from 14.7 to 313 nM. ► The proposed method was used to determine seven neurochemicals in urine.