Determination of Arsenic(III) at a Nanogold Modified Solid Carbon Paste Electrode

Abstract

A selective and sensitive electroanalytical method was developed for arsenic determination based on a nanogold (AuNP) modified solid carbon paste working electrode (SCPE) modified in two steps (i) physisorption and (ii) additional electrodeposition of nanogold particles in the presence of iodide. Copper(II) interference was solved by covering the gold layer by a self assembled mono layer (SAM) of glutathione. Using DPASV a linear response of the signal was obtained as a function of As(III) in the concentration range 0.05–20 µM (4–1498 ppb) with a limit of detection of 0.01 µM (0.9 ppb). Sample stirring and degassing were not needed. Application to the determination of arsenic(III) and (V) in underground water samples from Burkina Faso was successfully achieved.

Inorganic arsenic speciation by electroanalysis. From laboratory to field conditions: A mini-review

“…For example, LODs in the range 0.01-0.05 ppb are presented in [26,[36][37][38][39][40][41][42] and LOD lower than 0.005 ppb in [43][44][45][46][47][48]. A number of different approaches have been used to improve the sensitivity of detection:…”

“…This may be done by changing the composition of the background solutions [48,77] and the measured signal (As 35); or by modifying the surface using M-NPs, their composites [37,51,58,[78][79][80], ligands (-SH, -NH 2 ) or organic membranes [11,38,40,44,49,56,80]. Other effective methods employ flowthrough systems [82] or cation exchangers [43,75,[83][84][85][86].…”

“…(5) The analysis can be simplified by: the replacement of precious metal electrodes by inexpensive materials [44,47,33,60,[99][100][101][102][103][104]; analysis without removing oxygen from solution [38,55,75,91]; minimizing the sample preparation stage by eliminating the reduction of As(V) to As(III), and speciation of As in the field. Automation of procedures is helpful and there has been some research aimed at creating microfluidic total analysis systems which would be ideal for this purpose [4].…”

Possible Monitoring and Removal of As(III) by an Integrated System of Electrochemical Sensor and Nanocomposite Materials

“…A trace of As(III) in water can be detected by several methods, such as the inductively coupled plasma mass spectroscopy (ICP-MS) or atomic absorption spectroscopy (AAS). However, those instruments are expensive and complicated with long-time sample preparation [8]. Recently, electrochemical method has attracted a large attention of researchers thanks to its sensibility, low cost, and ability to detect very low concentration of analytes [8,9].…”

Gold Nano Particle and Reduced Graphene Oxide Composite Modified Carbon Paste Electrode for the Ultra Trace Detection of Arsenic (III)

“…Electrochemical method of determination of As is best suited in terms of easy instrumentation and field applicability using modified electrode. There have been enormous different ways of modification procedure investigated and several reviews are published on the determination of arsenic [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38], Carbon based electrode modified with gold nano particles has the advantage over other modified electrodes due to their ability to decrease the interferences from organic matrices and the interference due to some commonly occurring metal ions [39][40][41][42][43][44][45]. In two recent publications reduced graphene oxide and gold nano particles composite modified glassy carbon and thoria nano particles modified carbon paste electrodes were used for the determination of arsenic [46,47].…”