Voltammetric Detection of Cr(VI) with Disposable Screen-Printed Electrode Modified with Gold Nanoparticles

Abstract

Gold nanoparticle (Au-NP) enhanced voltammetric detection of Cr(VI) is developed for determination of trace amounts of Cr(VI) in an acetate buffer media (pH 4.6). The Au-NPs were electrodeposited onto a disposable screen printed electrode (SPE) via an electrodeposition step. It was found that the electrodeposited Au-NP has strong adsorption on Cr(VI) species, which results in an enhanced reduction current of Cr(VI). Compared with the bulk gold electrode, the reduction current of Cr(VI) was enhanced 10 times with the Au-NP-modified SPE electrode. Square wave voltammetric (SWV) measurement with the disposable Au-NP-modified SPE provides a fast, simple and sensitive detection of trace amounts of Cr(VI). The adsorption of Cr(VI) on Au-NP was characterized with voltammetry, X-ray photoelectron spectroscopy and ultraviolet spectra. The different parameters including the electrodepositing time, supporting electrolyte, and pH that govern the analytical performance of the electrode have been studied in detail and optimized. The detection limit of 5 microg L(-1) Cr (VI) was obtained under optimum experimental conditions. The performance of the sensor was successfully evaluated with river water samples spiked with Cr(VI), indicating this convenient and sensitive technique offers great promise for onsite environmental monitoring and biomonitoring of Cr(VI).

Gold nanoparticle-based biosensors

“…While bulk gold is chemical inert, recent studies show that nanosized GNPs exhibit extraordinary catalytic activity [102][103][104], which is utilized by several studies in electrochemical biosensing [105][106][107][108][109]. The catalytic properties of GNPs, which are believed to originate from the quantum scale dimension [110], the large surface-to-volume ratio and the interface-dominated properties [111,112], can decrease overpotentials of many analytically important electrochemical reactions, realize the reversibility of some redox reactions, and might even allow fabrication of enzyme-free biosensors.…”

Construction of Au nanoparticles on choline chloride modified glassy carbon electrode for sensitive detection of nitrite

“…Au nanoparticles have attracted considerable attention in electrochemical field because of their advantages of catalysis, mass transport, high effective surface area and control over surrounding environment (Liu and Ju, 2003;Liu et al, 2007;Tangkuaram et al, 2007;Suprun et al, 2008;Jia et al, 2009). It is shown that the catalytic performance of Au nanoparticles is markedly dependent on the structure of their local microenvironment (Miscoria et al, 2005;Welch and Compton, 2006).…”

Characteristics of Voltammetric Determination and Speciation of Chromium – A Review

“…Some mercury-free solid electrodes, such as bismuth film electrodes [97,147,148] or stannum film electrode [164], have been proposed as a substitute to the mercury liquid electrodes. Recently, the disposable screen-printed electrodes modified with poly-l-histidine film [165], gold nanoparticles [166] and silver or gold nanoparticles [167] have been applied as a voltammetric sensors for the voltammetric determination of Cr(VI). Moreover, nano-sized gold particles deposited on glassy carbon [168] or on the conductive substrate modified with sol-gel derived thiol [169] were also used to the mention above purpose.…”