期刊
ELECTROCATALYSIS
卷 12, 期 3, 页码 310-325出版社
SPRINGER
DOI: 10.1007/s12678-021-00658-7
关键词
Arsenic (III) {i.e. As (III)}; Band gap energy (E-g); Heavy metal ions (HMI); L-cysteine; Square-wave anodic stripping voltammetry (SWV-ASV); A-lipoic acid
资金
- National Research Foundation (NRF) of South Africa through the National Innovation Centre of the Advance Materials Division at Mintek
An ultrasensitive electrochemical sensor for detecting arsenic (III) has been developed, utilizing a sensing platform of L-cysteine molecules conjugated to reduced lipoic acid capped gold nanoparticles. The sensor demonstrated a low detection limit and a wide linear range, showing excellent recoveries in spiked samples for arsenic (III) detection in groundwater.
An ultrasensitive electrochemical sensor to detect arsenic (III), a highly toxic heavy metal ion, has been successfully developed. The sensing platform composed of L-cysteine (Lcyst) molecules conjugated to reduced lipoic acid (rLA) capped gold nanoparticles and exhibited an indirect band gap energy (E-g) of 1.96 eV. This is a characteristic of a semiconducting material; metals and semiconducting nanomaterials possess good electrochemical properties due to their trivial band gap energies. Surface ligation of the gold nanoparticles with rLA and Lcyst did not only prevent the nanoparticle agglomeration but also improved the susceptibility of the sensor to bind efficiently to heavy metal ions of interest. The electrochemical properties of the sensing platform were demonstrated by a reversible redox electron transfer reaction of the gold oxides due to the presence of gold nanoparticle clusters on the screen-printed carbon electrode surface. The sensor parameters such as the scan rate, pH and the deposition potential were optimised. The sensor was capable of detecting the arsenic (III) ions at the formal peak potential (E-pa degrees ') of -0.307 +/- 0.02 V. Subsequently, the sensor demonstrated a low limit of detection with the magnitude of 3 ppb (i.e. 3SD/SLOPE). The dynamic linear range of the developed sensing platform was between 3 and 25 ppb. The sensor was used to detect As(III) in ground water and demonstrated excellent recoveries in spiked samples.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据