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Du M, Chen Q, Xu X. A novel and label-free electrochemical aptasensor based on exonuclease III and G-quadruplex DNAzyme for sensitive and selective detection of metronidazole. Microchem J 2022. [DOI: 10.1016/j.microc.2022.107577] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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2
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Ali S, Mansha M, Baig N, Khan SA. Recent Trends and Future Perspectives of Emergent Analytical Techniques for Mercury Sensing in Aquatic Environments. CHEM REC 2022; 22:e202100327. [PMID: 35253977 DOI: 10.1002/tcr.202100327] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Revised: 01/29/2022] [Accepted: 02/22/2022] [Indexed: 11/10/2022]
Abstract
Environmental emissions of mercury from industrial waste and natural sources, even in trace amounts, are toxic to organisms and ecosystems. However, industrial-scale mercury detection is limited by the high cost, low sensitivity/specificity, and poor selectivity of the available analytical tools. This review summarizes the key sensors for mercury detection in aqueous environments: colorimetric-, electrochemical-, fluorescence-, and surface-enhanced Raman spectroscopy-based sensors reported between 2014-2021. It then compares the performances of these sensors in the determination of inorganic mercury (Hg2+ ) and methyl mercury (CH3 Hg+ ) species in aqueous samples. Mercury sensors for aquatic applications still face serious challenges in terms of difficult deployment in remote areas and low robustness, reliability, and selectivity in harsh environments. We provide future perspectives on the selective detection of organomercury species, which are especially toxic and reactive in aquatic environments. This review is intended as a valuable resource for scientists in the field of mercury sensing.
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Affiliation(s)
- Shahid Ali
- Interdisciplinary Research Center for Hydrogen and Energy Storage (IRC-HES), King Fahd University of Petroleum & Minerals (KFUPM), Dhahran, 31261, Saudi Arabia
| | - Muhammad Mansha
- Interdisciplinary Research Center for Hydrogen and Energy Storage (IRC-HES), King Fahd University of Petroleum & Minerals (KFUPM), Dhahran, 31261, Saudi Arabia
| | - Nadeem Baig
- Interdisciplinary Research Center for Membranes and Water Security, King Fahd University of Petroleum & Minerals (KFUPM), Dhahran, 31261, Saudi Arabia
| | - Safyan Akram Khan
- Interdisciplinary Research Center for Hydrogen and Energy Storage (IRC-HES), King Fahd University of Petroleum & Minerals (KFUPM), Dhahran, 31261, Saudi Arabia
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Wang S. Construction of DNA Biosensors for Mercury (II) Ion Detection Based on Enzyme-Driven Signal Amplification Strategy. Biomolecules 2021; 11:biom11030399. [PMID: 33800447 PMCID: PMC8001444 DOI: 10.3390/biom11030399] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 03/04/2021] [Accepted: 03/05/2021] [Indexed: 02/03/2023] Open
Abstract
Mercury ion (Hg2+) is a well-known toxic heavy metal ion. It is harmful for human health even at low concentrations in the environment. Therefore, it is very important to measure the level of Hg2+. Many methods, reviewed in several papers, have been established on DNA biosensors for detecting Hg2+. However, few reviews on the strategy of enzyme-driven signal amplification have been reported. In this paper, we reviewed this topic by dividing the enzymes into nucleases and DNAzymes according to their chemical nature. Initially, we introduce the nucleases including Exo III, Exo I, Nickase, DSN, and DNase I. In this section, the Exo III-driven signal amplification strategy was described in detail. Because Hg2+ can help ssDNA fold into dsDNA by T-Hg-T, and the substrate of Exo III is dsDNA, Exo III can be used to design Hg2+ biosensor very flexibly. Then, the DNAzyme-assisted signal amplification strategies were reviewed in three categories, including UO22+-specific DNAzymes, Cu2+-specific DNAzymes and Mg2+-specific DNAzymes. In this section, the Mg2+-specific DNAzyme was introduced in detail, because this DNAzyme has highly catalytic activity, and Mg2+ is very common ion which is not harmful to the environment. Finally, the challenges and future perspectives were discussed.
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Affiliation(s)
- Shuchang Wang
- School of Life Sciences, East China Normal University, Shanghai 200241, China
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Memon AG, Xing Y, Zhou X, Wang R, Liu L, Zeng S, He M, Ma M. Ultrasensitive colorimetric aptasensor for Hg 2+ detection using Exo-III assisted target recycling amplification and unmodified AuNPs as indicators. JOURNAL OF HAZARDOUS MATERIALS 2020; 384:120948. [PMID: 31610345 DOI: 10.1016/j.jhazmat.2019.120948] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 07/11/2019] [Accepted: 07/28/2019] [Indexed: 05/22/2023]
Abstract
Facile and ultrasensitive detection of Hg2+ in water environment remains challenging. Exonuclease III (Exo-III)-assisted target recycling is one of the most popular amplification strategies. Although the magnesium (II) ions are widely acting as cofactors of Exo-III, we recognized that Mg2+ cofactors would strongly disturb the charge distribution on citrate-stablized gold nanoparticles (in the general sense, unmodified AuNPs) surface, thus generate false positive colorimetric signals. To address this issue, we first put forward the view that the cobalt (II) ions can function as the Exo-III cofactor and successfully construct a novel label-free colorimetric aptasensor for facile and ultrasensitive detection of Hg2+ using Hg2+-triggered Exo-III-assisted signal amplification and unmodified AuNPs as indicators. A hairpin-looped DNA probe was rationally designed with thymine-rich recognition termini and specifically recognized trace Hg2+ by a stable T-Hg2+-T structure. A blue-to-red color change of AuNPs with the addition of Hg2+ provided the quantitative detection of Hg2+ with a limit of detection of 0.2 nM and a linear working range from 0.5 nM to 5.0 nM. The whole testing time for one assay was approximately 40 min. Real water samples, even containing Hg2+ at 1 nM, could be determined by the aptasensor with recovery rates from 97% to 103%.
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Affiliation(s)
- Abdul Ghaffar Memon
- Center for Sensor Technology of Environment and Health, State Key Joint Laboratory of ESPC, School of Environment, Tsinghua University, Beijing, 100084, China; Department of Environmental Engineering, NED University of Engineering and Technology, Karachi, 75270, Pakistan
| | - Yunpeng Xing
- Center for Sensor Technology of Environment and Health, State Key Joint Laboratory of ESPC, School of Environment, Tsinghua University, Beijing, 100084, China
| | - Xiaohong Zhou
- Center for Sensor Technology of Environment and Health, State Key Joint Laboratory of ESPC, School of Environment, Tsinghua University, Beijing, 100084, China.
| | - Ruoyu Wang
- Center for Sensor Technology of Environment and Health, State Key Joint Laboratory of ESPC, School of Environment, Tsinghua University, Beijing, 100084, China
| | - Lanhua Liu
- Center for Sensor Technology of Environment and Health, State Key Joint Laboratory of ESPC, School of Environment, Tsinghua University, Beijing, 100084, China
| | - Siyu Zeng
- Center for Sensor Technology of Environment and Health, State Key Joint Laboratory of ESPC, School of Environment, Tsinghua University, Beijing, 100084, China.
| | - Miao He
- Center for Sensor Technology of Environment and Health, State Key Joint Laboratory of ESPC, School of Environment, Tsinghua University, Beijing, 100084, China.
| | - Mei Ma
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
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Li Y, Liu Q, Chen Z. Optical aptasensing of mercury(II) by using salt-induced and exonuclease I-induced gold nanoparticle aggregation under dark-field microscope observation. Mikrochim Acta 2019; 186:729. [PMID: 31659462 DOI: 10.1007/s00604-019-3876-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 09/26/2019] [Indexed: 02/03/2023]
Abstract
An optical method for determination of Hg(II) is described that exploits the aggregation of gold nanoparticles (AuNPs) under dark-field microscope (DFM) observation. This assay is based on the use of a Hg(II)-specific aptamer, AuNPs modified with complementary DNA strands, and exonuclease I (Exo I). In the absence of Hg(II), the added dsDNA prevents salt-induced aggregation of the green-colored AuNPs. If Hg(II) is added, the aptamer will capture it to form T-Hg(II)-T pairs, and the complementary strand is digested by Exo I. On addition of a solution of NaCl, the AuNPs will aggregate. This is accompanied by a color change from green to orange/red) in the dark-field image. By calculating the intensity of the orange/red dots in the dark-field image, concentration of Hg(II) can be accurately determined. The limit of detection is as low as 36 fM, and response is a linear in the 83 fM to 8.3 μM Hg(II) concentration range. Graphical abstract Schematic representation of a colorimetric assay for Hg(II) based on the use of a mercury(II)-specific aptamer, gold nanoparticles modified with complementary DNA strands, and exonuclease I.
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Affiliation(s)
- Yanan Li
- Department of Chemistry, Capital Normal University, Beijing, 100048, China
| | - Qingyun Liu
- College of Chemical and Environmental Engineering, Shandong University of Science and Technology, Qingdao, 266590, China
| | - Zhengbo Chen
- Department of Chemistry, Capital Normal University, Beijing, 100048, China.
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Fluorometric determination of mercury(II) using positively charged gold nanoparticles, DNA-templated silver nanoclusters, T-Hg(II)-T interaction and exonuclease assisted signal amplification. Mikrochim Acta 2019; 186:317. [PMID: 31049707 DOI: 10.1007/s00604-019-3388-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 03/29/2019] [Indexed: 10/26/2022]
Abstract
The authors describe a method for detection of Hg2+ by using positively charged gold nanoparticles ((+)AuNPs) as a quencher of the fluorescence of DNA-capped silver nanoclusters (DNA-AgNCs) which are negatively charged. In the presence of Hg2+, a DNA duplex is formed through T-Hg2+-T coordination chemistry. The duplex can be digested by exonuclease III to form smaller DNA fragments. This leads to the release of the AgNCs and the recovery of fluorescence, best measured at excitation/emission wavelengths of 460/530 nm. The (+)AuNPs and Hg2+ are also released and can be reused for target recycling signal amplification. Based on these findings, a method is worked out for the determination of Hg2+ that works in the 5.0 pM to 10 nM concentration range and has a detection limit as low as 2.3 pM. It is highly selective because of the highly specific formation of T-Hg2+-T bonds. Graphical abstract By using ultrastable and positively charged gold nanoparticles as fluorescence quenchers and exonuclease assisted signal amplification, a method is developed for the sensitive and selective detection of Hg2+ in water samples.
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Fluorometric determination of mercury(II) via a graphene oxide-based assay using exonuclease III-assisted signal amplification and thymidine-Hg(II)-thymidine interaction. Mikrochim Acta 2019; 186:216. [PMID: 30838468 DOI: 10.1007/s00604-019-3332-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Accepted: 02/22/2019] [Indexed: 12/26/2022]
Abstract
A highly sensitive and selective fluorometric method is described for determination of mercury(II). It is based on (a) the use of graphene oxide (GO) acting as a quencher of the fluoresence of the carboxy-fluorescein (FAM), and (b) of Hg(II)-triggered cleavage of the newly formed nucleic acid sequences harbored blunt 3'-hydroxyl termini by exonuclease III (Exo III) that leads to signal amplification. Two DNA probes are used, viz. a capture probe (CP) and a help probe; HP) that is partially complementary. In the absence of Hg(II), the FAM-labeled hairpin (signal probe, SP) is adsorbed onto the surface of GO via π-stacking interactions. CP blocks the release of the HP for binding to SP. This results in quenching of the green fluorescence of the label. Upon addition of Hg(II), the linear structure of CP is converted to a hairpin structure due to the formation of thymidine-Hg(II)-thymidine duplexes. HP is released from the CP/HP hybrids, and this causes SP to be released from from GO and fluorescence to be recovered. The signal is strongly amplified by using Exo III-assisted targeting and recycling of HP. Hence, Hg(II) can be detected via the strong increase in fluorescence. The method has a linear response in the 0.1 to 30 nM Hg(II) concentration range and a 10 pM detection limit. It was applied to the determination of Hg(II) in three (spiked) Chinese medicines. Graphical abstract Schematic representation of fluorescence sensing strategy for Hg2+ by using graphene oxide as a quencher and exonuclease III-assisted signal amplification.
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Berlina AN, Zherdev AV, Dzantiev BB. Progress in rapid optical assays for heavy metal ions based on the use of nanoparticles and receptor molecules. Mikrochim Acta 2019; 186:172. [PMID: 30767144 DOI: 10.1007/s00604-018-3168-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Accepted: 12/09/2018] [Indexed: 02/06/2023]
Abstract
This review (with 230 refs.) covers recent progress in rapid optical assays for heavy metals (primarily lead and mercury as the most relevant) based on the use of nanoparticles and receptor molecules. An introduction surveys the importance, regulatory demands (such as maximum permissible concentrations) and potential and limitations of various existing methods. This is followed by a general discussion on the use of nanoparticles in optical assays of heavy metals (including properties, basic mechanisms of signal generation). The next sections cover methods for the functionalization of nanoparticles with (a) sulfur-containing compounds (used for modification of nanoparticles or added to the reaction medium), (b) nitrogen-containing compounds (such as amino acids, polypeptides, and heterocyclic molecules), and (c) oxygen-containing species (such as hydroxy and carbonyl compounds). This is continued by a specific description of specific assays based on the use of aptamers as receptors, on the use of deoxyribozymes as synthetic reaction catalysts, of G-quadruplex aptamers, of aptamers in logic gate-type of assays of linear (unstructured) aptamers ("hairpins"), and on the use of aptamers in lateral flow assays. A next section covers assays based on the employment of antibodies as receptors (used in the immunoassay development). The properties of various nanoparticles and their applicability in optical assays are also discussed in some detail. Final sections discuss the selectivity of assays, potential interferences by other cations, methods for their elimination, and also matrix effects and approaches for sample pretreatment. A concluding section discusses current challenges and future trends. Analysis based on enzyme inhibition assay is not treated here but enzyme-like action of some receptor molecules such as DNAzymes is discussed. Graphical abstract Schematic presentation of main principles of application of various nanoparticles with receptor molecules (S-, N-, O-containing, heterocyclic compounds, proteins, antibody, aptamers) for heavy metals ions detection. The included methods cover optical assays with description of mechanisms of interactions and signal generation.
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Affiliation(s)
- Anna N Berlina
- A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Leninsky prospect 33, Moscow, 119071, Russia
| | - Anatoly V Zherdev
- A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Leninsky prospect 33, Moscow, 119071, Russia
| | - Boris B Dzantiev
- A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Leninsky prospect 33, Moscow, 119071, Russia.
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Song X, Wang Y, Liu S, Zhang X, Wang H, Wang J, Huang J. Colorimetric and visual mercury(II) assay based on target-induced cyclic enzymatic amplification, thymine-Hg(II)-thymine interaction, and aggregation of gold nanoparticles. Mikrochim Acta 2019; 186:105. [PMID: 30637516 DOI: 10.1007/s00604-018-3193-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 12/20/2018] [Indexed: 11/28/2022]
Abstract
A colorimetric biosensor and visual test is described for the determination of mercury(II). It relies on the specific thymine-Hg(II)-thymine (T-Hg2+-T) interaction which induces a cyclic amplification process (caused by the enzyme exonuclease III) and the aggregation of gold nanoparticles. These results in a color change from red to violet. Under optimized conditions, this colorimetric assay (best performed at 524 nm) has a detection limit as low as 0.9 nM with a detection range over 4 orders of magnitude (from 1 nM to 10 μM). Graphical abstract Schematic of a colorimetric method for determination of mercury ions (Hg2+) based on the thymine-Hg2+-thymine interaction-triggered cyclic enzymatic amplification and aggregation of gold nanoparticles with the aid of exonuclease III (Exo III).
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Affiliation(s)
- Xiaolei Song
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, People's Republic of China
| | - Yu Wang
- College of Biological Sciences and Technology, University of Jinan, Jinan, 250022, People's Republic of China
| | - Su Liu
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, People's Republic of China
| | - Xue Zhang
- College of Biological Sciences and Technology, University of Jinan, Jinan, 250022, People's Republic of China
| | - Haiwang Wang
- College of Biological Sciences and Technology, University of Jinan, Jinan, 250022, People's Republic of China
| | - Jingfeng Wang
- College of Biological Sciences and Technology, University of Jinan, Jinan, 250022, People's Republic of China
| | - Jiadong Huang
- College of Biological Sciences and Technology, University of Jinan, Jinan, 250022, People's Republic of China. .,Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, College of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, People's Republic of China.
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Huang D, Liu X, Lai C, Qin L, Zhang C, Yi H, Zeng G, Li B, Deng R, Liu S, Zhang Y. Colorimetric determination of mercury(II) using gold nanoparticles and double ligand exchange. Mikrochim Acta 2018; 186:31. [DOI: 10.1007/s00604-018-3126-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 11/27/2018] [Indexed: 10/27/2022]
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Wang X, Yang X, Wang N, Lv J, Wang H, Choi MMF, Bian W. Graphitic carbon nitride quantum dots as an "off-on" fluorescent switch for determination of mercury(II) and sulfide. Mikrochim Acta 2018; 185:471. [PMID: 30238322 DOI: 10.1007/s00604-018-2994-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Accepted: 09/08/2018] [Indexed: 11/24/2022]
Abstract
A rapid method has been developed for the determination of Hg(II) and sulfide by using graphitic carbon nitride quantum dots (g-CNQDs) as a fluorescent probe. The interaction between Hg(II) and g-CNQDs leads to the quenching of the blue g-CNQD fluorescence (with excitation/emission peaks at 390/450 nm). However, the fluorescence can be recovered after addition of sulfide such that the "turn-off" state is switched back to the "turn-on" state. The g-CNQDs were fully characterized by transmission electron microscopy, X-ray diffractometry, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, UV-vis absorption and fluorescence spectroscopy. Under the optimal experimental conditions, this probe is highly selective and sensitive to Hg(II). The linear response to Hg(II) extends from 0.20 to 21 μM with a detection limit of 3.3 nM. In addition, sulfide can be detected via the recovery of fluorescence. The linear response range for sulfide species is from 8.0 to 45 μM with a detection limit of 22 nM. The mechanism of the "turn-off-on" scheme is discussed. The methods have been applied to the analysis of spiked tap water, lake water and wastewater samples. Graphical abstract Schematic of an off-on fluorescent probe for mercury(II). The fluorescence of graphitic carbon nitride quantum dots (g-CNQDs) is quenched by Hg2+ but is recovered after reacting with S2- as it can combine with Hg2+ on the surface of g-CNQDs.
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Affiliation(s)
- Xuan Wang
- Shanxi Medical University, Taiyuan, 030001, China
| | - Xuefang Yang
- Shanxi Medical University, Taiyuan, 030001, China
| | - Ning Wang
- Shanxi Medical University, Taiyuan, 030001, China
| | - Junjie Lv
- Shanxi Medical University, Taiyuan, 030001, China
| | | | - Martin M F Choi
- Bristol Chinese Christian Church, c/o Tyndale Baptist Church, 137-139 Whiteladies Road, Bristol, BS8 2QG, UK
| | - Wei Bian
- Shanxi Medical University, Taiyuan, 030001, China.
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Sensitive determination of Hg(II) based on a hybridization chain recycling amplification reaction and surface-enhanced Raman scattering on gold nanoparticles. Mikrochim Acta 2018; 185:363. [DOI: 10.1007/s00604-018-2907-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 06/29/2018] [Indexed: 01/09/2023]
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13
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Colorimetric determination of Hg(II) via the gold amalgam induced deaggregation of gold nanoparticles. Mikrochim Acta 2018; 185:351. [PMID: 29968011 DOI: 10.1007/s00604-018-2900-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Accepted: 06/28/2018] [Indexed: 10/28/2022]
Abstract
A method is described for the colorimetric determination of mercury(II). In the absence of Hg(II), aminopropyltriethoxysilane (APTES) which is positively charged at pH 7 is electrostatically absorbed on the surface of gold nanoparticles (AuNPs). This neutralizes the negative charges of the AuNPs and leads to NP aggregation and a color change from red to blue-purple. However, in the presence of Hg(II), reduced Hg (formed through the reaction between Hg(II) and citrate on the AuNP surface) will replace the APTES on the AuNPs. Hence, the formation of aggregates is suppressed and the color of the solution does not change. The assay is performed by measuring the ratio of absorbances at 650 and 520 nm and can detect Hg(II) at nanomolar levels with a 10 nM limit of detection. The specific affinity between mercury and gold warrants the excellent selectivity for Hg(II) over other environmentally relevant metal ions. Graphical Abstract Schematic of the method for determination of Hg2+ based on the gold amalgam-induced deaggregation of gold nanoparticles in the presence of APTES with the LOD of 10.1 nM.
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