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

Abstract

The simple, fast and highly sensitive anodic stripping voltammetric detection of As(III) at a gold (Au) nanoparticlemodified glassy carbon (GC) (nano-Au/GC) electrode in HCl solution was extensively studied. The Au nanoparticles were electrodeposited onto GC electrode using chronocoulometric technique via a potential step from 1.1 to 0 V vs. Ag j AgCl j NaCl (sat.) in 0.5 M H 2 SO 4 containing Na [AuCl 4 ] in the presence of KI, KBr, Na 2 S 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[AuCl 4 ] (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 À2 mM À1 and detection limit of 0.024 mM (1.8 ppb) were obtained using linear sweep voltammetry.

Electroanalysis of Trace Inorganic Arsenic with Gold Nanoelectrode Ensembles

“…In comparison with other nanostructured electrodes, DL at our NEEs compares or is even slightly lower than previous achievements [11][12][13][14][15].…”

“…In particular, several papers described the successful use of carbon electrodes modified with gold nanoparticles (AuNps) for trace arsenic analysis. The Au-Nps can be deposited by mean of electroless [13] or electrochemical methods [14,15]. The so prepared modified electrodes showed detection limit (DL) of 0.01 mg L À1 [11].…”

Anodic stripping voltammetric analysis of trace arsenic(III) enhanced by mild hydrogen-evolution at a bimetallic Au–Pt nanoparticle modified glassy carbon electrode

“…2C, under optimized conditions, the As (0) Fig. 2C) and those in many reported analogues [19,20], and the E cp is more positive than those reported previously even at comparable pH [21][22][23].…”

Gold Nanoparticle Modified Screen Printed Electrodes for the Trace Sensing of Arsenic(III) in the Presence of Copper(II)

“…Dai and Compton have reported that through the use of gold nanoparticle modified electrodes the interference from copper in the electroanalytical detection of arsenic(III) is overcome as the nanoparticle domains facilitate the adequate separation of the copper and arsenic stripping peaks [20]. This methodology has been extended [16] but still requires the formation of in-situ formed nanoparticles on solid electrode substrates. Other approaches have explored the addition of complexing agents to the electrolyte [22,23] or via modification of gold macroelectrodes with cysteine allowing the separation of the arsenic(III) and copper(II) stripping peaks [24].…”