ANALYTICAL AND BIOANALYTICAL CHEMISTRY
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2021
·Vol. 413
·期 28
·7001-7007
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IF 4.157
Sang Fuming,Yin Suyao,Pan Jianxin,Zhang Zhizhou
A novelty aptasensor for ultrasensitive detection of Hg 2+ is developed, exploiting the combination of plasmonic properties of gold nanoparticles (AuNPs) and exonuclease III (Exo III)-assisted target recycling for signal amplification. In the presence of Hg 2+ , a DNA duplex can be formed due to the strong coordination of Hg 2+ and T bases of single-stranded DNA (ssDNA) probe. Exo III digests the DNA duplex from the 3′ to 5′ direction, resulting in the releasing of Hg 2+ . Then, the released Hg 2+ binds with another ssDNA probe through T-Hg 2+ -T coordination. After Exo III-assisted Hg 2+ cycles, numerous ssDNA probes are exhausted, which promotes poly(diallyldimethylammonium chloride) (PDDA)-induced AuNP aggregation, leading to an obvious color change and aggregation-induced plasmon red shift of AuNPs (from 520 to 610 nm). Therefore, this biosensor is ultrasensitive, which is applicable to the detection of trace level of Hg 2+ with a linear range from 5 pM to 0.6 nM and an ultralow detection limit of 0.2 pM. Furthermore, it enables visual detection of Hg 2+ as low as 50 pM by the naked eye. More importantly, the assay can be applied to the reliable determination of spiked Hg 2+ in sea water samples with good recovery.
研究领域:
生物传感
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环境科学
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纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
·
2019
·
IF 5.256
Zhihong Li,Hongjing Sun,Xinyue Ma,Ruifang Su,Rui Sun,Chuanyu Yang,Chunyan Sun
A novel label-free fluorescence “turn-on” strategy was developed for the sensitive detection of Hg 2+ based on the thymine-Hg 2+ -thymine (T-Hg 2+ -T) coordination and the fact that single-stranded DNA (ssDNA) greatly enhances the fluorescence of terbium (III) (Tb 3+ ), but double-stranded DNA (dsDNA) does not. In the absence of Hg 2+ , the mercury-specific DNA (MSD) hybridized with the corresponding complementary strand (cDNA) to form a double helix structure in solution based on Watson-Crick base pairings, which cannot enhance the fluorescence of Tb 3+ . In the presence of Hg 2+ , MSD preferentially bound with Hg 2+ to form the T-Hg 2+ -T complex due to the strong affinity of Hg(II) for the T bases of DNA, thus avoiding the hybridization of the cDNA to MSD. The free cDNA can greatly enhance the emission of Tb 3+ , leading to a sharp increase in fluorescence intensity . Under the optimized conditions, the increased fluorescence intensity was proportional to the concentration of Hg 2+ in the range from 10 to 600 nM, and this method can detect concentrations of Hg 2+ as low as 0.24 nM. Moreover, satisfactory results were obtained for the detection of Hg 2+ in river water and fish samples, and the results were consistent with those from the atomic fluorescence spectroscopy (AFS). Thus, the fluorescence characteristics of Tb 3+ were here used in a “turn on” approach to detect Hg 2+ , which represents a new opportunity for Hg 2+ analysis in the field of environmental monitoring and food safety.
研究领域:
环境科学
·
食品安全
·
分析化学
✓ 已验证
DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
·
2024
·
IF 5.7
Weichen Meng,Xiaochun Han,Rui Han,Xinchao Zhang,Xianghua Zeng,Jizhou Duan,Xiliang Luo
The monitoring of heavy metal ions in ocean is crucial for environment protection and assessment of seawater quality. However, the detection of heavy metal ions in seawater with electrochemical sensors, especially for long-term monitoring, always faces challenges due to marine biofouling caused by the nonspecific adsorption of microbial and biomolecules. Herein, an electrochemical aptasensor, integrating both antifouling and antibacterial properties, was developed for the detection of Hg 2+ in the ocean. In this electrochemical aptasensor, eco-friendly peptides with superior hydrophilicity served as anti-biofouling materials, preventing nonspecific adsorption on the sensing interface, while silver nanoparticles were employed to eliminate bacteria. Subsequently, a ferrocene-modified aptamer was employed for the specific recognition of Hg 2+ , leveraging the aptamer's ability to fold into a thymine-Hg 2+ -thymine (T-Hg 2+ -T) structure upon interaction, and bringing ferrocene nearer to the sensor surface, significantly amplifying the electrochemical response. The prepared electrochemical aptasensor significantly reduced the nonspecific adsorption in seawater while maintaining sensitive electrochemical response. Furthermore, the biosensor exhibited a linear response range of 0.01–100 nM with a detection limit of 2.30 pM, and realized the accurate monitoring of mercury ions in real marine environment. The research results offer new insights into the preparation of marine antifouling sensing devices, and it is expected that sensors with antifouling and antimicrobial capabilities will find broad applications in the monitoring of marine pollutants.
研究领域:
环境科学
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分析化学
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海洋生物学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2022
·
IF 4.598
Libo Li,Bainian Chen,Xiaohong Liu,Panao Jiang,Lijun Luo,Xia Li,Tianyan You
Divalent mercury ion (Hg 2+ ) is widely distributed in the ecological environment and harmful to the human body and the environment. Herein, a highly sensitive and selective ‘on–off-on’ electrochemiluminescence (ECL) aptamer sensing method based on the dual signal amplification strategy of a self-enhanced luminophore and ECL resonance energy transfer (ECL-RET) was developed to detect Hg 2+ . In detail, the first ‘switch-on’ state was obtained by the self-enhanced luminophore of Ru(bpy) 3 2+ -doped silica nanoparticle-nitrogen-doped graphene quantum dots ( [email protected] 2 -NGQDs) modified glassy carbon electrode, which significantly amplified the ECL intensity compared with the mixture of [email protected] 2 and NGQDs . Later, the ‘switch-off’ state was induced by gold nanoparticles (AuNPs), which acted the acceptor in the ECL-RET system between AuNPs and [email protected] 2 -NGQDs due to their good spectral overlap. This combination of the self-enhanced luminophore and ECL-RET provided a novel dual signal amplification strategy, which led to a high signal-to-noise ratio and high analysis sensitivity. Finally, upon the addition of Hg 2+ , the formation of a stable T-Hg 2+ -T structure induced the release of AuNPs from the sensing interface and halted the ECL-RET process, resulting in ECL signal recovery (the second ‘switch-on’ state). For the detection of Hg 2+ , the proposed ECL sensor exhibited a wide linear range from 1 × 10 −14 to 1 × 10 −6 M and a highly sensitive detection limit of 3.0 fM. Finally, the feasibility of the developed method in water sample analysis was investigated.
研究领域:
分析化学
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环境科学
·
材料科学
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纳米技术
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传感器技术
✓ 已验证
产品关联
DOI
高影响因子
TALANTA
·
2020
·
IF 5.339
Libo Li,Bainian Chen,Lijun Luo,Xiaohong Liu,Xiaoya Bi,Tianyan You
In the present study, a novel self-enhanced electrochemiluminescence (ECL) aptasensor which combined self-enhanced ECL composite as signal response element and aptamer as the specific recognition element was firstly proposed for the sensitive and selective detection of Hg 2+ . Innovatively, the luminophore Ru(bpy) 3 2+ -doped silica nanoparticles functionalized with 3-aminopropyltriethoxysilane (NH 2 – [email protected] 2 ) and the co-reactant nitrogen doped graphene quantum dots (NGQDs) were bound together to form the self-enhanced ECL composite, NH 2 – [email protected] 2 -NGQDs, by electrostatic adsorption. Satisfactorily, high and stable luminous efficiency of NH 2 – [email protected] 2 -NGQDs was obtained benefited from the short electron transfer distance and low energy loss of self-enhanced-typal ECL composite. For the fabrication of the self-enhanced ECL aptasensor for Hg 2+ detection, the Hg 2+ aptamer, of which one end was connected to NH 2 – [email protected] 2 -NGQDs, and the other end was fixed on glass carbon electrode (GCE) surface through Au–S bond, was served as a bridge. Upon the addition of Hg 2+ , the aptamer was bent due to the formation of thymine-Hg 2+ -thymine (T-Hg 2+ -T) specific structure, which caused the self-enhanced ECL composite was close to the GCE surface. On this basis, a linearly enhanced ECL signal was acquired with the concentration of Hg 2+ in the range of 5.0 × 10 −11 M − 1.0 × 10 −6 M with excellent selectivity , repeatability and stability in 3 min for each assay. In addition, the proposed aptasensor showed satisfying accuracy and practicability for Hg 2+ analysis in tap and canal water verified by the inductively coupled plasma-mass spectrometry (ICP-MS) method.
研究领域:
分析化学
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环境科学
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纳米技术
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）