Selective Determination of Epinephrine in the Presence of Ascorbic Acid on a Carbon Nanotubes Modified Electrode Based on the Enhancement Effects of the Hexadecyl Trimethyl Ammonium Bromide

A modified glassy carbon electrode (GCE) was fabricated by covered with a layer of multi-wall carbon nanotubes (MWCNTs) coated with hexadecyl trimethyl ammonium bromide (CTAB). The modified electrode showed excellent electrochemical catalytic properties for the redox of epinephrine (EP) and ascorbic acid (AA). In the presence of CTAB, the peak separation between EP and AA can be broadened to 256 mV by the CTAB. Based on this, a sensitive method for determination of EP and AA was set up. The detection limits were 3.0×10-8 mol/L and 1.0×10-4 mol/L (S/N=3) for EP and AA, respectively. The proposed method was used to detection of EP and AA in injections with simplicity, high sensitivity and selectivity