Analytical Methods
·
2018
·Vol. 10
·期 34
·4183-4188
·
IF 2.073
Renjun Wang,Xiaolu Yan,Jing Sun,Xiao Wang,Xian-En Zhao,Wei Liu,Shuyun Zhu
In this contribution, DNA-templated silver nanoclusters (DNA-AgNCs) were successfully utilized as novel fluorescent probes for the detection of quinolones for the first time. The as-prepared DNA-AgNCs exhibited strong emission at 596 nm, which could be quenched by Cu2+ ions. The addition of quinolones caused restoration of fluorescence intensity of the DNA-AgNCs–Cu2+ system. This detection protocol exhibited excellent sensitivities for four kinds of quinolones. For instance, the linear ranges were from 20 to 100 nM for nalidixic acid with the limit of detection (LOD) 2.0 nM, from 5 to 120 nM for cinoxacin with the LOD 1.2 nM, from 5 to 100 nM for ciprofloxacin with the LOD 1.0 nM, and from 1 to 60 nM for moxifloxacin with the LOD 96 pM, respectively. Benefiting from high sensitivity, satisfactory recoveries were obtained for trace detection of quinolones in real samples, such as tablets and human urine.
研究领域:
分析化学
·
纳米技术
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
Biosensors-Basel
·
2023
·Vol. 13
·期 5
·520
·
IF 5.4
Guowen Li,Xiufang Huang,Chifang Peng,Fengxia Sun
It is still challenging to achieve simultaneous and sensitive detection of multiple organophosphorus pesticides (OPs). Herein, we optimized the ssDNA templates for the synthesis of silver nanoclusters (Ag NCs). For the first time, we found that the fluorescence intensity of T base-extended DNA-templated Ag NCs was over three times higher than the original C-riched DNA-templated Ag NCs. Moreover, a “turn-off” fluorescence sensor based on the brightest DNA-Ag NCs was constructed for the sensitive detection of dimethoate, ethion and phorate. Under strong alkaline conditions, the P-S bonds in three pesticides were broken, and the corresponding hydrolysates were obtained. The sulfhydryl groups in the hydrolyzed products formed Ag-S bonds with the silver atoms on the surface of Ag NCs, which resulted in the aggregation of Ag NCs, following the fluorescence quenching. The fluorescence sensor showed that the linear ranges were 0.1–4 ng/mL for dimethoate with a limit of detection (LOD) of 0.05 ng/mL, 0.3–2 µg/mL for ethion with a LOD of 30 ng/mL, and 0.03–0.25 µg/mL for phorate with a LOD of 3 ng/mL. Moreover, the developed method was successfully applied to the detection of dimethoate, ethion and phorate in lake water samples, indicating a potential application in OP detection.Keywords:fluorescence sensor;DNA-templated silver nanoclusters;organophosphorus pesticides;fluorescence quenching
研究领域:
分析化学
·
环境科学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2022
·Vol. 12
·期 46
·30024-30029
·
IF 4.036
Baozhu Zhang,Ziyao Yang,Yuxia Li,Ling Ma,Fenfang Li,Xiuqing Lv,Guangming Wen
A label-free aptasensor has been fabricated in order to detect adenosine triphosphate (ATP) using turn-on fluorescence DNA-Ag NCs. The fluorescence of the DNA-Ag NCs could increase remarkably with the addition of ATP mainly because ATP specifically interacts with its aptamer to change the microenvironment of the darkish DNA-Ag NCs located at one terminus or two termini due to the conformational alteration of the aptamer structure. The proposed sensor can detect ATP in a linear range of 6–27 mM with a good detection limit of 5.0 μM. Additionally, the proposed method succeeded in detecting ATP in fetal bovine serum.
研究领域:
分析化学
·
生物传感器
·
纳米技术
✓ 已验证
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2018
·
IF 5.667
Jiao Wang,Ziying Zhang,Xia Gao,Xiaodong Lin,Yaqing Liu,Shuo Wang
Lead ion (Pb 2+ ) is known as a major non-degradable environmental pollutant and is quite harmful to human health. In our investigation, a novel ratiometric fluorescent nanosensor with DNA-AgNCs as single fluorophore has been successfully constructed for ultrasensitive and specific detection of Pb 2+ . The single-strand DNA templated silver nanoclusters present green emission, which can be converted into red emission after approaching a specific DNA segment by forming duplex with its complementary DNA strands (ds-DNA-AgNCs). The ds-DNA-AgNCs contains rA cleavage site of Pb 2+ -dependent DNAzyme configuration. In the presence of Pb 2+ , the specific DNA segment would be released from the ds-DNA-AgNCs, resulting in discoloration of DNA-AgNCs from red to green. Since Pb 2+ can successively cleave the rA site, the signal change from red to green emission is amplified. Thus, benefiting from the Pb 2+ -dependent DNAzyme and the charming properties of DNA-AgNCs, the proposed platform exhibits a good linear relationship from 0.001 nM to 10 nM with a detection limit of 1.0 pM for Pb 2+ determination, which is lower than most of the reported Pb 2+ biosensors. Moreover, this sensitive ratiometric fluorescent probe exhibits excellent selectivity toward Pb 2+ detection in real samples, such as lake water, tap water, and human serum samples, illustrating the huge potential applications for complicated samples in the future.
研究领域:
生物化学
·
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2021
·
IF 7.514
Yixia Yang,Behafarid Ghalandari,Liyun Lin,Xiao Sang,Wenqiong Su,Adeleh Divsalar,Xianting Ding
The abuse application of glyphosate can result in a potential hazard for environment and human, however its ultrasensitive detection remains challenging. Herein, a Cu 2+ modulated DNA-templated silver nanoclusters (DNA-AgNCs) sensor was constructed to sensitively determine glyphosate based on the turn-on fluorescence strategy. The fluorescence quenching of DNA-AgNCs occurred with the existence of Cu 2+ . Upon the presence of glyphosate, the functional groups on the surface of glyphosate could chelate with Cu 2+ , following the fluorescence recovery of DNA-AgNCs. Through the stoichiometric methods, we unveil that Cu 2+ -trigged fluorescence quenching mode is a combination of static and dynamic quenching with the static mode being predominant. In DNA-AgNCs/Cu 2+ system, the carboxylate, amine, and phosphonate groups of glyphosate interact with Cu 2+ through chelation, in which the carboxylate oxygen, the phosphonate oxygen atoms, and the monoprotonated secondary amine nitrogen atom and Cu 2+ form chelate rings. This fluorescence sensor showed a desired linearity of glyphosate analysis under the optimum conditions, ranging from 15 to 100 μg/L with a low detection down to 5 μg/L. Moreover, the proposed sensor was successfully utilized to measure glyphosate in real samples, indicating a promising application in pesticide residues detection.
研究领域:
分析化学
·
环境科学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2024
·Vol. 14
·期 8
·5594-5599
·
IF 3.9
Yuxia Li,Zeting Meng,Yating Liu,Baozhu Zhang
A turn-on fluorescence nanoprobe was constructed for the determination of adenosine 5′-triphosphate (ATP) based on DNA-templated silver nanoclusters (DNA-AgNCs). The significant enhancement fluorescence intensity of DNA-AgNCs in the presence of ATP is due to the high special binding affinity between ATP and the aptamer, resulting in the environment of DNA-AgNCs with darkish fluorescence lying at one terminus of DNA slightly altering owing to the change of ATP aptamer conformation. A good linear range runs from 9 to 24 mM with a satisfactory detection limit of 3 μM. Furthermore, the proposed nanoprobe exhibited good performance for ATP detection in diluted fetal bovine serum.
研究领域:
分析化学
·
纳米技术
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2017
·
IF 4.233
Wei-Xian Wang,Yuqing Wu,Hong-Wei Li
The aggregation-induced emission (AIE) phenomenon of the metal nanoclusters (NCs) has been discovered quite recently, which is considered to be creative to improve the optical properties of NCs upon ligand aggregation. In the present study, we report an AIE system for double-stranded DNA-templated silver nanoclusters (AgNCs-dsDNA) by using bovine serum albumin (BSA) in solution, which induce a moderate emission enhancement of AgNCs (5-fold) and a blue-shift through a loosen interaction. In addition, significant luminescence enhancement (30-fold) is further stimulated by the addition of digestive enzyme to the system by altering the surface structure of the aggregated particles. The processes are observed directly through transmission electron microscopy (TEM), where the dispersed AgNCs spheres are aggregated in a large incompact sheet-like film by BSA; while further trypsin addition lead them into larger particles (>50 nm) with higher density. And the intrinsic mechanism is explained well by UV–vis absorption and time-resolved luminescence spectra. The observed luminescence enhancement in step-II is attributed to the AIE through stronger interaction between the hydrolysates of BSA and the ligand dsDNA. Therefore, the optical properties of AgNCs-dsDNA are regulated well by the addition of BSA and trypsin in different amounts, which relates directly to the degree of aggregation and can be extended to other metal nanoclusters by employing the pairs of protein and related enzyme.
研究领域:
纳米技术
·
光学材料
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanoscale
·
2018
·Vol. 10
·期 23
·11079-11090
·
IF 7.233
Jingpu Zhang,Yanlei Liu,Xiao Zhi,Chunlei Zhang,Tie Fu Liu,Daxiang Cui
Dysregulation of microRNAs (miRNAs) is correlated with cancer progression. In vitro detection methods using extracts from cell lysis cannot provide information about the spatial distribution of miRNAs. Due to the development of miRNA fluorescence in situ hybridization (FISH), increasing amounts of intracellular expression information are being obtained. However, miRNA FISH suffers from weak signals and complex steps and thus remains very challenging. Herein, a strategy based on DNA-templated silver nanoclusters (AgNCs/DNAs) and their G-rich fluorescence enhancement effect was developed for FISH detection of miRNAs in gastric cancer cells. The method combines hybridization and signal amplification into one step, which allows imaging of intracellular miRNAs immediately after hybridization. Most importantly, using the method based on our design, miR-101-3p, miR-16-5p and miR-19b-3p were found to be located in the nuclei of MGC803 cells with granulated shapes, indicating an unanticipated distribution pattern. In addition, before the final miRNA FISH, we performed an optimization of AgNCs/DNAs and their G-rich fluorescence enhancement effect; we found that the effect occurred at shorter wavelengths emitting green fluorescence, with weakened red fluorescence at longer wavelengths. However, the components involved in the FISH process impacted the fluorescence properties so greatly that the probes finally exhibited slightly strengthened red fluorescence signals. Our method enables facile visualization of miRNAs at the subcellular level, which may benefit the precise localization of miRNAs in single cells in the future.
研究领域:
癌症生物学
·
分子生物学
·
纳米技术
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Food Measurement and Characterization
·
2024
·
IF 2.9
Cheng Jun-Hu,Zhang Xinxue,Ma Ji,Sun Da-Wen
Tropomyosin (TM), the major allergen in shellfish, is a common protein cause of allergenic diseases, hence a sensitive, efficient method for TM detection is urgently needed to protect allergy sufferers in food products. In this work, a novel fluorescent aptasensor for TM-sensitive detection based on DNA-templated silver nanoclusters (AgNCs) and catalytic hairpin assembly (CHA) was designed. With the rapid separation and enrichment of magnetic beads, the detection of TM was converted to the detection of cDNA (complementary DNA). Then the cDNA was utilized as the initiator to successfully trigger the CHA amplification technique, which ultimately formed double-stranded to induce high fluorescence signals by AgNCs. Specifically, the cDNA could trigger repeated cycles, which enabled signal amplification and enhanced aptasensor performance with an excellent linear relationship in a wide linear range from 0.1 to 50 μg/mL (R 2 = 0.9967) and a desirable low detection limit of 0.0179 μg/mL. It is worth noting that the method was successfully validated with high specificity and stability for detecting processed shrimp products, implying great potential in the field of allergen assay.
研究领域:
食品科学
·
分析化学
·
生物传感器
·
过敏测试
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2020
·Vol. 413
·期 6
·1541-1547
·
IF 3.637
Zhang Hong,Liu Pengfei,Wang Huifang,Ji Xiaoming,Zhao Mingqin,Song Zhaopeng
In the article, a simple and label-free strategy was proposed for the sensitive detection of lysozyme based on the fluorescence quenching of positively charged gold nanorods ((+)AuNRs) to DNA-templated silver nanoclusters (DNA/AgNCs). To construct the sensor, a DNA template was designed with a C-rich sequence at the 5′-terminal for the synthesis of AgNCs, while a lysozyme binding aptamer (LBA) at the 3′-terminal for the recognition of lysozyme, and such DNA/AgNCs was used as the fluorescence probe. Meantime, the fluorescence signal of such DNA/AgNCs can be quenched based on the electrostatic adsorption of them with (+)AuNRs, due to the surface energy transfer. In the presence of lysozyme, the specific binding happened between the LBA section of DNA/AgNCs and lysozyme, inducing the reduction of the total charge of DNA/AgNCs and weakening the adsorption of them with (+)AuNRs, which directly resulting in the recovery of the fluorescence signal. Besides, the fluorescence signal recovery of DNA/AgNCs has a linear positive proportional relationship with lysozyme concentration in the range of 10 pM–2.0 nM under the optimal conditions. Moreover, a satisfactory recovery (99.6–107.2%) was obtained while detecting lysozyme in human serum samples.
A simple and label-free strategy was proposed for the sensitive detection of lysozyme based on the fluorescence quenching of positively charged gold nanorods ((+)AuNRs) to DNA-templated silver nanoclusters (DNA/AgNCs).
研究领域:
分析化学
·
纳米技术
·
生物传感器
·
分子诊断
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Yiting Jiang,Minxuan Sun,Nan Ouyang,Yuguo Tang,Peng Miao
Herein, we develop a novel and effective combination nanoplatform for cancer theranostics. Folic acid (FA) is first modified on the photothermal agent of polydopamine (PDA), which possesses excellent near-infrared (NIR) absorbance and thermal conversion features. Temperature-sensitive silver nanoclusters (AgNCs) are then synthesized on the DNA template that also loads the anticancer drug doxorubicin (Dox). After accumulation in cancer cells, PDA generates cytotoxic heat upon excitation of NIR light for photothermal therapy. On the other hand, the temperature increment is able to destroy the template of AgNCs, leading to the fluorescence variation and controlled release of Dox for chemotherapy. The combined nanosystem exhibits outstanding fluorescence tracing, NIR photothermal transduction, as well as chemo drug delivery capabilities. Both in vitro and in vivo results demonstrate excellent tumor growth suppression phenomena and no apparent adverse effects. This research provides a powerful targeted nanoplatform for cancer theranostics, which may have great potential value for future clinical applications.
研究领域:
生物医学工程
·
纳米技术
·
癌症研究
·
诊疗学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2019
·
IF 9.518
Ya Cao,Yuhao Dai,Hong Chen,Yingying Tang,Xu Chen,Ying Wang,Jing Zhao,Xiaoli Zhu
In this work, DNA-templated silver nanoclusters (DNA-AgNCs) with unique fluorescent and electrochemical properties are prepared as dual signal probes for both qualitative imaging and quantitative detection of cancer cells in an integrated system . ITO electrode that has good light transmittance and electric conductivity is employed as a substrate for dual analysis of cancer cells. ITO electrode is firstly modified by AS1141 aptamer , which could selectively bind to nucleolin overexpressed on the surface of a model breast cancer cell, MCF-7 cell line. The composite of mucin 1 antibody (anti-MUC1) and DNA-AgNCs then binds to MUC1 on the surface of captured MCF-7 cell, forming a sandwich-like structure. Therefore, our method allows noninvasive fluorescence imaging and amplified electrochemical detection using a single labeling platform, providing a biocompatible and highly specific method for adequate analysis of cancer cells. Experimental results demonstrate that strong red fluorescence of DNA-AgNCs clearly displays the loading of cancer cells on ITO electrode after dual recognition, and amplified electrochemical signals of DNA-AgNCs enable improved sensitivity toward quantitative analysis with a detection limit of 3 cells.
研究领域:
生物医学工程
·
分析化学
·
癌症研究
·
纳米技术
✓ 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）