Surface effects of mesoporous silica modified electrode and application in electrochemical detection of dopamine

Mesoporous silica nanoparticles (meso-SiO(2)) were synthesized and used to modify the sui face of carbon paste electrode (CPE). The surface properties of CPE and meso-SiO(2)/CPE were examined Compared with the unmodified CPE, meso-SiO(2)/CPE remarkably enhances the peak currents of K(3)[Fe(CN)(6)] The effective surface areas of CPE and meso-SiO(2)/CPE were calculated to be 0.042 cm(2) and 0 208 cm(2), indicating that meso-SiO(2) possesses notable sui face enhancement effect Moreover, the electrochemical behaviors of dopamine (DA) were examined At the meso-SiO(2)/CPE, the oxidation signals of DA greatly increase, and the oxidation potential shifts negatively, suggesting that meso-SiO(2)/CPE exhibits catalytic activity to DA Based on this, a sensitive and simple electrochemical method was developed for the detection of DA The linear range is from 04 mu M to 25 mu M, and the limit of detection is as low as 0 1 mu M (C) 2009 Elsevier B V All rights reserved