SENSORS AND ACTUATORS B-CHEMICAL
·
2017
·
IF 5.401
Lili Yu,Wei Lan,Hui Xu,Hou Chen,Liangjiu Bai,Wenxiang Wang
We constructed a fluorometric and sensitive analysis of mercury (II) based on toehold-mediated strand displacement reaction, exonuclease III (Exo III) assisted target recycling, hybridization chain reaction (HCR), fluorescence intercalator SYBR Green I (SG) and grapheme oxide (GO). Firstly, toehold-mediated strand displacement reaction was constructed by using thymine-Hg 2+ -thymine (T-Hg 2+ -T) recognition mechanism between the helper hairpin DNA and assisted DNA. And then, the Exo III disintegrated the double-stranded DNA (dsDNA) by catalyzing the gradual removal of mononucleotides from 3′-hydroxyl terminus of dsDNA with a blunt 3′ terminus. It resulted in the target and assisted DNA recycling and released a trigger strand DNA at the same time. Finally, the trigger strand DNA initiated the hybridization chain reaction (HCR), forming long double helices, which achieved a secondary amplification due to the continuous target recycling, trigger strand DNA release and HCR. The number of T-T mismatches, the concentration of SG, Exo III and GO, the incubation time of Exo III were all optimized. Under the optimized condition, the limit of detection for Hg 2+ can be down to 7.37 pM with a linear range from 0 to 1.5 nM. This sensor exhibits high selectivity against other metal ions, and it works well for real samples.
研究领域:
分析化学
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纳米技术
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环境科学
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生物技术
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产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
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2022
·
IF 10.723
Congwei Li,Lian Duan,Xinjian Cheng
Fluorescent chitosan-based hydrogel for the selective detection and adsorption of Hg 2+ /Hg + in aqueous environment was prepared through three-step synthesis strategy. NO 2 -Boron-dipyrrolemethene (BODIPY) was prepared firstly, and then the -NO 2 group was reduced to -NH 2 group. Finally, the NH 2 -BODIPY was introduced to chitosan by Schiff base formation reaction through bi-aldehyde. Eventually, fluorescent chitosan hydrogel was obtained. The as-prepared fluorescent hydrogel probe could detect Hg 2+ /Hg + through PET mechanism with the detection limit of 0.3 μM. The recognition site which combines Hg 2+ /Hg + is C N, it is just formed in the reaction with chitosan and the amino group on BODIPY. Adsorption capacity of the fluorescent hydrogel is 121 mg·g −1 , which is almost seven times of the original chitosan. The isotherm and kinetics of Hg 2+ /Hg + removal follows Langmuir isotherm and pseudo-second order kinetics , respectively. Besides, a series of fluorescent hydrogels were prepared to compare the elasticity, hydropHilicity , fluorescence intensity and adsorption capacity.
研究领域:
材料科学
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环境科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
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2016
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IF 7.476
Chenyang Mei,Dajie Lin,Chengchao Fan,Aili Liu,Shun Wang,Jichang Wang
A Hg 2+ electrochemical biosensor is developed by integrating thymine–Hg 2+ –thymine (T–Hg 2+ –T) base pairs for the high selectivity with surface-initiated enzymatic polymerization (SIEP) for signal amplification . The fabrication begins with the covalent conjugation of capture DNA probe labeled with thiol at its 3′terminal onto the gold electrode. The presence of Hg 2+ leads to DNA hybridization, in which complementary DNA was captured onto the biosensor surface, which subsequently catalyzed the addition of deoxynucleotides (dNTP) containing biotinlated 2′-deoxyadenosine 5′-triphosphate (biotin-dATP) by terminal deoxynucleotidyl transferase (TdT). The binding between biotin and strepavidin leads to the attachment of a large number of strepavidin functionalized silver nanoparticles (strepavidin-AgNPs), which could generate electrochemical stripping signal of silver to monitor the concentration of Hg 2+ in KCl solution. Through utilizing the T–Hg 2+ –T selectivity and SIEP amplification, this assay method can detect aqueous Hg 2+ with a wide linear range from 0.05 nM to 100 nM and a detection limit of 0.024 nM. The application of this sensor in the analysis of drinking water demonstrates that the proposed method works well for real 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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DOI
PubMed
高影响因子
RSC Advances
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2017
·Vol. 7
·期 89
·56289-56295
·
IF 3.108
Baozhu Zhang,Chunying Wei
A novel turn-on Hg2+ sensor was constructed based on fluorescent C–Hg2+-aptamer DNA-stabilized Ag nanoclusters (DNA–AgNCs), and was used to determine the concentration of Hg2+ over the range 2–18 nM with a detection limit as low as 0.25 nM. The sensing assay relied on a target-induced conformational transition of Hg2+-aptamer DNA. The conformational change of Hg2+-aptamer DNA from a single strand to a hairpin DNA due to the formation of a T–Hg2+–T complex in the presence of Hg2+ made the two darkish DNA–AgNCs approach each other closely and then enhanced the fluorescence of the AgNCs, which enabled the sensitive and specific detection of Hg2+. The proposed sensor was found to be easy to use, and allowed for the sensitive, selective, and turn-on detection of Hg2+. Furthermore, this approach has also been successfully applied to the detection of Hg2+ in real water samples, so this sensor may find application in monitoring Hg2+ in environmental samples.
研究领域:
分析化学
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环境科学
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生物传感
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
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2020
·Vol. 44
·期 16
·6635-6642
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IF 3.288
Mingyu Tang,Guojuan Ren,Fang Chai
This article reports a one-pot hydrothermal strategy for preparing fluorescence carbon dots with magnetic properties (Fe3O4-CDs). Ammonium ferric citrate (AFC) and urea served as the iron and nitrogen sources and both as carbon sources were put into the reaction solvent diethylenetriamine (DETA), which acted as a reductant and nitrogen provider in the process of the synthesis of Fe3O4-CDs. Further, a sensitive and rapid method based on the Fe3O4-CDs was utilized for the detection of Hg2+, simultaneously accompanied with a magnetic removal process. Good linearity was obtained in the range from 2.0 to 200.0 nM with a detection limit of 12.6 nM. The fluorescence quenching mechanism was proved to be caused by an inner-filter effect (IFE) and static quenching effect (SQE). More, this platform was successfully applied for the analysis of Hg2+ in a real sample with satisfying recovery results, thus demonstrating its utility as a convenient monitoring strategy.
研究领域:
分析化学
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环境科学
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材料科学
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产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2017
·
IF 5.401
Sujing Wang,Xin Li,Jiaqing Xie,Bingying Jiang,Ruo Yuan,Yun Xiang
Hg 2+ ions are highly toxic and bioaccumulative pollutant that can lead to adverse toxicological effects on environment and human health, and the establishment of simple and sensitive methods for the detection of trace Hg 2+ ions is thus of great significance. On the basis of a new metal ion-triggered and DNA-fueled molecular machine strategy, we have established a sensitive and convenient approach for detecting Hg 2+ in different water samples without involving in any enzymes or nanomaterials for signal enhancement. The target Hg 2+ ions associate with the DNA complex probes through the formation of specific thymine-Hg 2+ -thymine (T-Hg 2+ -T) mismatched base pairing, which results in the release of the fluorescently quenched ssDNA from the complex probes to expose the pre-blocked toeholds. Subsequently, the fuel DNA further binds to the toeholds and triggers the operation of the molecular machine via strand displacement reactions to recycle the target ions, leading to the release of many fluorescently quenched ssDNAs for amplified monitoring of Hg 2+ within the dynamic range of 0.1–100 nM with a detection limit of 65 pM. Besides, with specific T-Hg 2+ -T coordination, the established approach shows high selectivity to the target ions and can be employed to detect Hg 2+ in tap and river water samples.
研究领域:
生物化学
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环境科学
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分析化学
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DOI
高影响因子
ACS Applied Nano Materials
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2024
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IF 5.3
Rongzhen Ma,Lin Chang,Long D. Nghiem,Yuan Liu,Qilin Wang,Qianbin Zhao,Qingju Hao,Yimeng Gao,Hong Liu,Lei Zheng
Carbon dots have emerged as highly efficient and versatile fluorescent probes for detecting and quantifying Hg2+. This study reports a method to prepare nitrogen-doped carbon dots (N-CDs) via ligand-to-metal charge transfer fluorescent quenching for Hg2+ detection. Besides the excitation-independent emission feature, the synthesized N-CDs demonstrate a high selectivity of Hg2+ over 23 potentially interfering environmental ions. The structures of 2-hydroxy-N,N-dimethylbenzamide and amide functional groups are identified as the determinants of the relatively high quantum yield (53.33%). N-CDs also exhibit a linear relationship with Hg2+ concentration in the range of 0.007–120 μM, with a limit of detection of 7.1 nM. The produced N-CDs can be employed in a customized microfluidic real-time monitoring platform, demonstrating the robustness in receiving efficient fluorescence signals with a satisfactory limit of detection. The acceptable accuracy and recovery of Hg2+ detection in tap water and river water highlight the potential practical applications of the synthesized N-CDs. Results in this study can facilitate the development of a portable device for early warning of water pollution.
研究领域:
环境科学
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化学
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产品关联
DOI
高影响因子
Journal of Nanostructure in Chemistry
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2014
·Vol. 4
·期 3
·1-8
·
IF 0
Li Lihua,Feng Dexiang,Fang Xian,Han Xiaowei,Zhang Yuzhong
In this work, we have developed a novel visual Hg 2+ sensor in aqueous solution using unmodified Au@Ag core–shell nanoparticles at room temperature, based on a redox reaction between Ag-shell and Hg 2+ . The prepared Au@Ag core–shell nanoparticles exhibited good monodispersity. In the presence of Hg 2+ , Hg 2+ was reduced into Hg (0) by Ag-shell, and deposited on the surface of Au-core to form Au–Hg alloys and caused nanoparticles aggregation, leading to the color changes of the solution from yellow to purplish red, and the surface plasmon resonance spectra of Au@Ag core–shell nanoparticles red shift. Under the optimal conditions, the visual sensor could selectively detect Hg 2+ as low as 0.4 µM with the naked eye and 5.0 nM by UV–vis spectra analysis methods. The designed sensor had several advantages: (1) the nanoparticles surface need not be functionalized. (2) The color change of the solution was in 2 s and could easily be observed with naked eyes. The visual sensor had been applied to detection of Hg 2+ in tap and lake water, which obtained satisfied result.
研究领域:
分析化学
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环境科学
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纳米技术
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产品关联
DOI
SENSORS AND ACTUATORS B-CHEMICAL
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2016
·
IF 4.758
Juan Wu,Wei Jiang,Aipeng Deng,Yewen Shen,Wei Jiang,Renbing Tian
In this work, a high-performance probe for Hg 2+ detection has been successfully synthesized based on Rhodamine B isothiocyanate (RBI) and thioglycolic acid (TA) co-modified Fe 3 O 4 @Au nanocomposites. The probe has many favorable properties, including suitable size and magnetic response (46.28 emu/g). Importantly, the fluorescence changes of the probe are remarkably specific for Hg 2+ in the presence of other competitive cations, and the limit of detection (LOD) for Hg 2+ in aqueous solutions is lower (3.03 nM) than the value of the World Health Organization (30 nM), which meet the selective and sensitive requirements for practical application. Interestingly, due to the magnetic responsive performance of Fe 3 O 4 , the probe can be recycled by a magnet and reused by addition of free RBI into Fe 3 O 4 @Au solutions that were already used for Hg 2+ detection. Furthermore, the experiments of probe for monitoring Hg 2+ inside human umbilical vein endothelial (HUVEC) cells reveal that the probe has biocompatibility and low cytotoxicity, and can effectively detect Hg 2+ in a short time. All the results presented in this study show that the proposed probe has significant potential for Hg 2+ detection in environmental and biological samples.
研究领域:
分析化学
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生物医学
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
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2013
·
IF 2.144
Huilin Tao,Xiufen Liao,Mingze Xu,Shuhuai Li,Fuxin Zhong,Zhongsheng Yi
The fluorescence resonance energy transfer between fluorescent brightener (FB, donor) and CdTe quantum dots (CdTe QDs, acceptor) was studied and a new method for detecting Hg 2+ ions in water samples was accordingly developed in this paper. It was found that the effective energy transfer occurred from FB to CdTe QDs in Tris–HCl buffer solution at pH=8.2, in which the QDs' fluorescence intensity increased greatly. Then the fluorescence quenching occurred as Hg 2+ interacted with CdTe. Under the optimized conditions, there was a linear relationship between the fluorescence quenching intensity and the concentration of Hg 2+ . Hg 2+ could be determined in the concentration range of 8.0×10 −9 –8.0×10 −7 g L −1 with a detection limit of 6.6×10 −10 g L −1 ( S / N =3). The method was applied to the determination of Hg 2+ in water samples via the standard addition method, and the recovery rate obtained was 97.3–105.5%.
研究领域:
分析化学
·
环境科学
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DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2022
·
IF 9.221
Kaiqi Liu,Luminita Marin,Xinjian Cheng
In this work, fluorescent β- cyclodextrin (β-CD) based probes containing naphthalimide group were synthesized to realize the specific recognition of Hg 2+ /Hg + in aqueous system. Firstly, three small fluorescent molecules (N1, N2 and N3) with -NH 2 groups were synthesized from 4-bromo-1, 8-naphthalene anhydride . Secondly, CH CCH 2 - group was introduced into β-CD by Williamson ether formation reaction. Finally, the target probes (β-CD-PI, β-CD-PY and β-CD-TP) were obtained by Amino-Yne click reaction. These probes can efficiently recognize Hg 2+ /Hg + . β-CD-PI emits bright yellow fluorescence after binding with Hg 2+ /Hg + , which is a turn-on fluorescent probe . When the Hg 2+ /Hg + concentration exceeds 26 μM, the fluorescence intensity amplifies sharply (20 folds). The hydrophobic parts of the probes aggregated together to form a micelle-like structure due to complexation with Hg 2+ /Hg + , resulting in special micelle-sensitizing properties. Meanwhile, the HOMO-LUMO energy levels of the probes were calculated by cyclic voltammetry (CV). The probe is expected to be used for the detection of Hg 2+ /Hg + in aqueous solutions without any organic solvents.
研究领域:
分析化学
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环境科学
·
材料科学
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产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2021
·
IF 8.067
Fei Pan,Chunyi Tong,Zhaoyang Wang,Fenghua Xu,Xiaofei Wang,Baicheng Weng,Dawei Pan,Rilong Zhu
Two kinds of novel sulfhydryl functionalized covalent organic frameworks were fabricated as adsorbents for the removal of ultra-trace concentrations of Hg 2+ from water. The two kinds of sulfhydryl functionalized covalent organic frameworks were obtained via a thiol-ene click reaction between the thiol groups of trithiocyanuric acid (TTC) or bismuththiol (BMT) and vinyl groups on the surface of covalent organic frameworks. The material structure was characterized by XRD, SEM, EDS, FT-IR, BET, and TG analysis. Due to their rich sulfur content, both adsorbents (COF-SH-1 and COF-SH-2) exhibited a high level of selective Hg 2+ removal from aqueous solution with maximum adsorption capacities of 763.4 mg g −1 and 526.3 mg g −1 , respectively. Furthermore, in the presence of ultra-low concentrations of Hg 2+ both materials exhibited excellent performance, achieving rapid Hg 2+ removal at concentrations from 10 μg L −1 to less than 0.02 ng L −1 . Analysis of the adsorption mechanism indicates that the sulfur containing chelating groups exhibit a strong binding capacity for Hg 2+ . Results show that the structure determines the performance, with the amount of adsorption sites being related to the adsorption capacity. Therefore, as sulfhydryl functionalized covalent organic frameworks contain an abundance of adsorption sites, these materials can effectively achieve the removal of ultra-low trace Hg 2+ concentrations and have promising future application potential for the environmental detection of heavy metals.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
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