ANALYTICA CHIMICA ACTA
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2023
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IF 6.2
Bodong Wang,Shan Pu,Chengyan Xia,Xiandeng Hou,Kailai Xu
Background Recently, headspace single-drop microextraction (HS-SDME) has attracted some attention for developing sensitive and selective colorimetric assays due to its excellent capability to reduce matrix interference and enrich analytes. However, the single droplet limits direct visual observation of color change and its quantitative measurement suffers from reduced optical path length. Therefore, amplifying the detection signals in both volume and intensity is an important and challenging task for improving the sensitivity, stability, and accuracy of such colorimetric analysis . Results In this study, a "headspace-nanoenzyme" (HS-NE) strategy was proposed that successfully addressed these challenges and enabled the colorimetric and fluorescent dual-mode detection of trace Hg 2+ . Atomic Hg 0 , generated via chemical vapor generation (CVG), underwent headspace reaction with AuNPs droplet to form Au@HgNPs, thus catalyzing the oxidation of o -phenylenediamine (OPD) in the presence of H 2 O 2 . The absorbance and fluorescence intensity of oxidized OPD were proportion to the concentration of Hg 2+ in the sample solution. Due to the greatly enhanced peroxidase-like activity by Au@HgNPs, the limit of detection was as low as 0.98 nM and 0.21 nM for the colorimetric and fluorescent modes, respectively. The applicability of this assay was further demonstrated with determination of Hg 2+ in real environmental and biological samples. Moreover, a convenient and cost-effective paper-based sensing platform was fabricated for rapid on-site detection of Hg 2+ . Significance and novelty This novel HS-NE strategy combines HS-SDME and nanoenzyme-based sensing to achieve dual effects of eliminating matrix interference and amplifying the measurement signal, resulting in improved accuracy, enhanced stability, high sensitivity, and exceptional selectivity , with great potential for on-site determination of trace Hg 2+ .
研究领域:
分析化学
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环境科学
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生物医学
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产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2016
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IF 4.758
Linghao He,Shuai Zhang,Minghua Wang,Donglai Peng,Fufeng Yan,Zhihong Zhang,Liming Zhou
Two novel nanocomposites of zinc phosphate [Zn 3 (PO 4 ) 2 ] and Hg 2+ -targeted DNA [Zn 3 (PO 4 ) 2 @DNA] and Zn 3 (PO 4 ) 2 and multi-wall carbon nanotubes (MWCNTs) modified with Hg 2+ -targeted DNA [Zn 3 (PO 4 ) 2 @MWCNTs-DNA] were fabricated by the assembly of Hg 2+ -targeted DNA strands with Zn 2+ ions. Two as-prepared nanocomposites were subsequently used as electrochemical biosensors for sensitively detecting Hg 2+ due to the combination effect of the formation of T–Hg 2+ –T coordination between DNA strands and Hg 2+ and the direct adsorption of Hg 2+ onto porous nanocomposites. In comparing with Zn 3 (PO 4 ) 2 @DNA nanocomposite, the crystallization degree of Zn 3 (PO 4 ) 2 @MWCNTs-DNA was improved due to the presence of MWCNTs, which further enhance electrochemical activity of the nanocomposite. As a result, Zn 3 (PO 4 ) 2 @MWCNTs-DNA nanocomposite-based electrochemical biosensor showed a higher sensitivity toward Hg 2+ detection in aqueous solution than Zn 3 (PO 4 ) 2 @DNA-based biosensor. It showed a detection limit of 0.071 nM within the range of 0.1–50 nM of the concentration of Hg 2+ . This newly developed biosensor also presented excellent selectivity, repeatability, and applicability in Hg 2+ detection. Therefore, the fabricated Zn 3 (PO 4 ) 2 -based nanocomposite using this novel strategy showed their considerable potential use in water or environmental treatment.
研究领域:
环境科学
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分析化学
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生物传感技术
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产品关联
DOI
高影响因子
JOURNAL OF FLUORESCENCE
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2025
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IF 3.1
Yao Jie,Chen Hongfang,Yang Xiaohua,Iqbal Muzaffar,Bian Wei
Mercury ions (Hg 2+ ) are categorized as environmental pollutants, which distributed in water, soil, and food systems due to environmental contamination. Hence, designing a sensitive assay for the convenient determination of Hg 2+ is of great importance. Herein, S and O-doped graphite phase nitrogenized carbon quantum dots (S, O-C 3 N 4 QDs) was encapsulated within a europium -based metal-organic framework (Eu-MOF) to construct a novel ratiometric fluorescent nanoprobe for the quantitative detection of Hg 2+ . The native emission of S, O-C 3 N 4 QDs at 445 nm is used as a response signal, while Eu-MOF with fluorescence offers a reference signal at 619 nm. Hg 2+ exhibits high affinity for the surface functional groups of S/O-C 3 N 4 QDs, forming non-fluorescent chelation complexes that induce static quenching. This results in significant attenuation of the fluorescence intensity at 445 nm, while the emission at 619 nm remains invariant. A ratiometric fluorescence sensing platform was established based on the intensity ratio (F 445 /F 619 ) for the selective detection of Hg 2+ . The linear range of S, O-C 3 N 4 QDs/Eu-MOF of Hg 2+ was 0.25–35 µM and with a detection limit of 4.3 nM. The satisfying results demonstrate the effectiveness of the developed S, O-C 3 N 4 QDs/Eu-MOF-based fluorescence probe for Hg 2+ detection, highlighting its promising potential for environmental monitoring applications.
研究领域:
环境科学
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分析化学
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材料科学
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纳米技术
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产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2020
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IF 7.1
Hui Liu,Jinshui Wang,Huali Jin,Min Wei,Wenjie Ren,Yurong Zhang,Ligen Wu,Baoshan He
A sensitive electrochemical biosensor was constructed for Hg 2+ detection based on peonylike Cu-MOFs in situ growth of PtPd NPs bimetallic label S 1 and Mg 2+ -dependent DNAzyme-driven DNA Walker dual amplification signal strategy. The hairpin DNA (HP) and signal label [email protected] NPs/S 1 were first used to self-assemble on the gold nanorods/poly (diallyldimethylammonium chloride) functionalized graphene (AuNRs/PDDA-Gr) modified electrode, at this time, Cu ions can undergo a valence change to produce a larger initial signal. Here, we designed S 2 that can perform dual functions and contains two sequences, on was a substrate sequence of the Mg 2+ -dependent DNAzyme and the other was a sequence complementary to HP. In the presence of target Hg 2+ , HP was opened and hybridized with enzymatically sequenced DNA Walker (S 2 ) to preferentially form thymine-Hg 2+ -thymine (T-Hg 2+ -T). Then, DNA Walker exhibited catalytic activity of DNAzyme in the presence of Mg 2+ to continuously cleave [email protected] NPs/S 1 , resulting in a decrease of electrochemical signal. Under optimal conditions, the change of current was linearly related to the negative logarithm of the Hg 2+ concentration in the detection range of 0.001–100 nM with a low detection limit of 0.52 pM. Moreover, the proposed aptasensor was successfully applied in detection of milk powder samples.
研究领域:
分析化学
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环境科学
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生物化学
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纳米技术
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食品安全
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）