Palladium nanoparticles modified electrode for the selective detection of catecholamine neurotransmitters in presence of ascorbic acid

Palladium (Pd) nanoparticles are directly fabricated on glassy carbon electrode (GCE) and indium tin oxide electrode (ITO) by simple electrochemical deposition process. The Pd nanoparticles modified ITO electrode surface has been studied in detail using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The electrodeposited nano Pd particles are found as spherical shaped in the size range of 39-78 nm. The X-ray diffraction (XRD) analysis reveals that the electrodeposited nano Pd film possesses the face centered cubic crystalline structure. This nano Pd film modified GCE effectively exhibits the electro oxidation signals for the detection of catecholamines epinephrine (EP), norepinephrine (NEP) and dopamine (DA). Especially, the proposed nano Pd film modified GCE successfully showed two well separated anodic oxidation peaks for the detection of catecholamines and ascorbic (AA) in mixture solution. The proposed nano Pd film modified electrode also retains the advantage of easy fabrication, high sensitivity and good repeatability. Finally, this type of nano Pd film modified electrode supports the selective detection of catecholamines in injection solutions. (C) 2009 Elsevier B.V. All rights reserved.