ANALYTICAL AND BIOANALYTICAL CHEMISTRY
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2022
·Vol. 414
·期 22
·6581-6590
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IF 4.478
Wang Junyang,Liu Zheng,Li Ying,Yang Chuanyu,Ma Xinyue,Li Hongxia,Sun Chunyan
Based on a Pb 2+ -specific 8–17 DNAzyme-induced catalytic hairpin assembly (CHA), a simple signal-on fluorescence strategy for lead ion detection was established. 8–17 DNAzyme was used as the recognition element of Pb 2+ , which catalyzed the cleavage of the RNA base embedded in the DNA substrate strand, while releasing part of the substrate strand (S’) as CHA initiator. And two hairpin probes (H1 and H2-FQ) were designed according to the sequence of S’ for CHA, in which H2-FQ was labeled with the fluorophore FAM and quencher BHQ-1 as fluorescent “molecular switch” based on fluorescence resonance energy transfer (FRET). In the presence of Pb 2+ , the CHA reaction was triggered to form a large number of H1-H2 complexes, enabling enzyme-free isothermal amplification and a signal-on fluorescence strategy. In the concentration range of 0.5–1000 nM, the fluorescence signal increases with the increase of Pb 2+ concentration. The quantitative detection limit of Pb 2+ by this method is 0.5 nM, which has better detection performance compared with the FQ-labeled 8–17 DNAzyme method. The established biosensor exhibits good specificity and can be effectively used for the detection of Pb 2+ in real samples of river water and grass carp. Through ingenious nucleic acid sequence design, DNAzyme and CHA reactions are integrated to realize the enzyme-free isothermal amplifications and sensitive detection of Pb 2+ , which holds potential versatility in food supervision and environmental monitoring. Graphical abstract
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
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2021
·
IF 7.46
Bingyan Yan,Shaohua Xu,Fang Luo,Bin Qiu,Zhenyu Lin,Ying Wang
Small amount of lead ions (Pb 2+ ) can cause great harm to human health, it is important to develop some simple but sensitive methods to detect Pb 2+ quickly and accurately. In this study, a sensitive method has been developed for Pb 2+ detection based on the difference of gold monomer ratio using a dark field microscope (DFM) as readout system. The proposed method employed single-particle gold nanoparticles (AuNPs) and 8–17 DNAzyme as signal converter and identification unit, respectively. The 8–17 DNAzyme consists of a catalytic strand and a substrate strand, the 5′ end of the two strands are modified with sulfhydryl groups. The 8–17 DNAzyme is firmly modified on the surface of AuNPs (50 nm, AuNPs1) in advance, in the absence of Pb 2+ , AuNP aggregation is occurred by adding AuNPs (20 nm, AuNPs2) as they can interact with the other end of the dsDNA. In the presence of Pb 2+ , due to the specific cleavage of the substrate chain by Pb 2+ , another –SH leaves away from AuNPs1, the aggregation of AuNPs cannot be occurred. AuNP aggregates can be easily distinguished from the monomers under DFM because the aggregation can induce green-to-yellow scattering color changing, and the monomer ratio summarized by Image J can be used for quantitative analysis . The linear response range is 0.1–100.0 pM with a detection limit of 0.075 pM. The proposed method has been applied to detect Pb 2+ in lake water and human blood serum samples with satisfied results.
研究领域:
生物化学
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纳米医学
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环境科学
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2017
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IF 6.065
Wang Ren,Ying Zhang,Yu Zhu Fan,Jiang Xue Dong,Nian Bing Li,Hong Qun Luo
A resonance Rayleigh scattering (RRS) aptasensor was fabricated for detection of Pb 2+ via hairpin-like label-free substrate and G-wire for signal amplification. A hairpin-like DNA substrate contains a sequence in the loop labeled with ribonucleobase A and c-myc sequence in the stem. When hybridized with 8–17 DNAzyme in the presence of Pb 2+ , the sequence in the loop was activated and cleaved. Hundreds of c-myc sequences departing from the 8–17 DNAzyme yield nanowires superstructure called G-wire in the presence of Mg 2+ . The polymer G-wire was demonstrated by the RRS spectrum, polyacrylamide gel electrophoresis, and AFM. The RRS intensity was enhanced by the product G-wires, and the RRS signal at 370 nm was linear with the logarithm of Pb 2+ concentration in the range of 2.0 nM to 5.0 μM. This method was selective for Pb 2+ even coexisting with other metal ions at high concentrations and was successfully applied to the determination of Pb 2+ in real samples. The aptasensor holds a great promise for universal RRS sensing platform for sensitive detection of various metal ions just by changing the sequence of the probe in the loop and DNAzyme.
研究领域:
分析化学
·
环境科学
·
生物化学
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产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2023
·
IF 8.4
Xinghui Zhou,Chengpeng Li,Wanxue Wang,Feng Zhang,Yi Zhou,Danping Chen,Zhenchao Wang
N 6 -methyladenosine (m 6 A) is a crucial post-transcriptional epigenetic modification in RNAs which associates with numerous cancers development. Here, a cost-effective, and easy-to-operate fluorescence strategy for m 6 A analysis was developed based on the different cleavage efficiency of 8–17 DNAzyme for methylation and unmethylation sites. By arranging 8–17 DNAzyme to recognize and cleave 5'-rAG-3' and 5'-rm 6 AG-3' motifs in the target sequence respectively, various short ssDNA oligoes were produced, leaving different amounts of target sequence. Benefiting from the varying degrees of retardation of CHA amplification reaction, the tiny discrepancy between m 6 A and unmethylated adenine (A) can be distinguished. Moreover, we found that 8–17 DNAzyme was more sensitive to m 6 A than to A. Importantly, the strategy we proposed not only avoids sophisticated chemical labelling and expensive proteins, but also can be easily performed on the ordinary heating apparatus of accessible laboratory. The DCHA strategy demonstrated good analytical performance in complex biological matrices, and was successfully applied to hepatocellular carcinoma-related m 6 A analysis in CTNNB1, MGAT5 and SOCS-2 mRNAs with satisfactory results, showing its potential in clinical analysis.
研究领域:
分子生物学
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生物化学
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癌症生物学
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表观遗传学
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产品关联
DOI
高影响因子