Biothiol-Functionalized Cuprous Oxide Sensor for Dual-Mode Sensitive Hg²⁺ Detection

Abstract

Hg2+ ions are one of the highly poisonous heavy metal ions in the environment, so it is urgent to develop rapid and sensitive detection platforms for detecting Hg2+ ions. In this work, a novel electrochemical and photoelectrochemical dual-mode sensor (l-Cys-Cu2O) was successfully fabricated, and the sensor exhibits a satisfactory detection limit (0.2 and 0.01 nM) for the detection of Hg2+, which is far below the dangerous limit of the U.S. Environmental Protection Agency. The linear ranges of dual-mode Hg2+ detections were 0.33–3.3 and 0.17–1.33 μM, respectively. Moreover, the sensor shows desirable stability, selectivity, and reproducibility for detecting Hg2+ ions. For river water samples, the recoveries of 96.6–101.4% (electrochemical data) and 93.0–105.6% (photoelectrochemical data) were obtained, indicating that the sensor could be successfully applied in the determination of Hg2+ ions in environmental water. Therefore, the designed sensor has a potential in the trace-level detection of Hg2+ ions.

Rapid Determination of Mercury Ions in Environmental Water Based on an N-Rich Covalent Organic Framework Potential Sensor

“…e lower limit of detection can be deduced to be 4.5 × 10 −12 mol/L according to the plotting method. Comparing the GPE/ COF TFPB-TZT with other modi ed electrodes reported using di erent nanomaterials [32][33][34][35][36][37], as shown in Table 1, it can be seen that the COF TFPB-TZT -modi ed biosensor in this work has better properties with a wider linear range and higher sensitivity.…”

Development of Palladium on Bismuth Sulfide Nanorods as a Bifunctional Nanomaterial for Efficient Electrochemical Detection and Photoreduction of Hg(II) Ions

“…LOD values were achieved for various modified electrodes with substrates such as GCE, ITO, FTO, AuE, CFME, MCPE, etc. Among them, the modified electrodes employed included Cu 2 O–S, WS 2 film, AuPtNPs/ITO, Cu 2 O–S/FTO, Cu-MOF/GCE, Av-HA/GCE, chitosan/CPE, Pd/PAC/GCE, Au-PEDOT/GCE, calixarene/SPCCEs, Au-SH/rGO/GCE, N,S-doped C@Pd NRs/GCE, ssDNA/AuE, AuNPs-CF, PFF/MWCNTs, Au@HS-rGO, HNTs-Fe 3 O 4 -MnO 2, MnMoO 4 /GCE, etc. as given in Table along with our results, which demonstrate the merit of the Pd@Bi 2 S 3 /GCE in the detection of Hg 2+ ions.…”

“…Hg 2+ has a strong affinity for S-containing groups like thiols and sulfides, which has been widely discussed. ,,, In this aspect, to inspect the selectivity of the proposed electrode using DPV, the detection of Hg 2+ ions tested in the presence common metal ions (Mg 2+ , Na + , Ca 2+ , Ba 2+ , Li + , Cd 2+ , and Pb 2+ ) and biomolecules like glucose (Glu), methionine (MT), and hydrogen peroxide (H 2 O 2 ) in PB (pH 5.0) was examined. Figure e shows an assessable current response in the designated voltage regime of −0.2 to 0.6 V. The DPV response of 50 μL (0.01 M) of Hg 2+ was obtained in the presence of 100 μL (0.01 M) of other interferents, which were added for the selectivity examination under otherwise the same experimental conditions.…”

“…Thus far, the commonly used detection methods include atomic absorption spectrometry, inductively coupled plasma (ICP), conventional methods, and so on. , However, the employment of the aforementioned methods are limited in their application due to the use of expensive equipment, time consumption, and other factors that restrict applicability. Therefore, utilizing the conventional, possibly accruable techniques with rapid results like electrochemical detectors for trace amount of Hg 2+ ions has attracted great attention. − …”

Self-Powered Photoelectrochemical Assay for Hg2+ Detection Based on g-C3N4-CdS-CuO Composites and Redox Cycle Signal Amplification Strategy

“…As illustrated in Scheme 1B, under irradiation, glutath (GSH) is oxidized by CuO to form oxidized glutathione (GSSG) for generating a str photocurrent owing to the GSH-oxidase and peroxidase-like activities of CuO NPs [24 In the presence of GSH reductase (GR), GSSG is reduced to GSH using a reductive c zyme II (NADPH) as a substrate, resulting in a redox cycle system [26], signal ampli tion is achieved through redox cycle. However, in the presence of Hg 2+ , GSH can bin Hg 2+ based on the hard-soft acid-base (HSAB) theory [27], which influences the ab redox cycle system and significantly reduces the photocurrent. Based on these results can conclude that the g-C3N4-CdS-CuO composite was successfully used to develo spPEC senor for the detection of Hg 2+ in human urine and artificial saliva.…”