Anodic Stripping Voltammetric Detection of Arsenic(III) at Gold Nanoparticle-Modified Glassy Carbon Electrodes Prepared by Electrodeposition in the Presence of Various Additives

The simple, fast and highly sensitive anodic stripping voltammetric detection of As(III) at I gold (Au) nanoparticle-modified glassy carbon (GC) (nano-Au/GC) electrode in HCI solution was extensively studied. The ALL nanoparticles were electrodeposited onto GC electrode using chronocoulometric technique via it potential step from 1.1 to 0 V vs. Ag vertical bar AgCl vertical bar NaCl (sat.) in 0.5 M H2SO4 containing Na[AuCl4] in the presence of KI, KBr, Na2S and cysteine additives. Surfaces of the resulting nano-AU/GC electrodes were characterized with cyclic voltammetry. The performances of the nano-Au/GC electrodes, which were prepared using different concentrations of Na[AuCl4] (0.05-0.5 mM) and KI additive (0.01-1.0 mM) at various deposition times (10-30 s), for the voltammetric detection of As(III) were examined. After the optimization, a high sensitivity of 0.32 mA cm(-2) mu M-1 and detection limit of 0.024 mu M (1.8ppb) were obtained using linear sweep voltanirnetry.