ANALYTICAL CHEMISTRY
·
2021
·
IF 6.986
Junhua Chen,Gu Shi,Chong Yan
A visual detection method was proposed for polychlorinated biphenyls (PCBs) detection using lateral flow test paper as the sensing platform. The aptamer sequence was used to recognize the target 3,3′,4,4′-tetrachlorobiphenyl (PCB77). The integration of Zn2+-dependent DNAzyme with toehold-mediated strand displacement reaction significantly improved the response signals. Gold nanoparticles were utilized as the signal tracers in the test paper, making the results visible directly by the naked eye. Under optimal conditions, the paper enables the visual detection of PCB77 as low as 10 pM without additional instrumentation. The assay displays a high selectivity for PCB77 against potential interfering molecules. The visual test paper is robust and has been applied to the detection of PCB77 in milk samples with good recovery and satisfactory accuracy. Using two different PCBs (PCB77 and PCB72) as inputs, we further fabricated OR and AND logic gates, which is conducive to the development of an intelligent detection strategy for PCBs monitoring. Given the attractive characteristics of disposability, low cost, logic operation, and intuitive output, the test paper shows great promise for on-site screening of PCBs in resource-limited areas.
研究领域:
分析化学
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环境科学
·
生物传感
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DOI
PubMed
高影响因子
JOURNAL OF FOOD COMPOSITION AND ANALYSIS
·
2021
·
IF 4.556
Yue-Hong Pang,Yi-Ying Wang,Meng-Meng Sun,Xiao-Fang Shen
The cauliflower mosaicvirus 35S (CaMV35S), as the most common promoter, has a usage rate of 70 % in transgenic crops, especially in dicots. Herein, a visual detection method of rolling circle amplification (RCA) combined with DNAzyme technology was developed for the determination of CaMV35S gene. A template sequence of the G-quadruple gene was designed for combining with the target gene CaMV35S. When the target gene existed, the RCA reaction occurred through the action of the enzyme, and the product combined with hemin to generate DNAzyme, which catalyzed the color reaction of 2′-hydrazine-bis-3-ethylbenzothiazolin-6-sulfonic acid (ABTS). Under the optimal experimental conditions, the linear range is 1 × 10 −13 ∼1 × 10 -8 mol/L, and the detection limit is 3 × 10 -14 mol/L (S/N = 3). The method has been successfully applied to standard samples and practical samples (soybean and tofu). For verifying the feasibility and reliability, real-time fluorescent quantitative PCR method was used to detect the target gene CaMV35S, and the results were in good agreement with those of our method, indicating that our developed method can be used for the determination of actual samples.
研究领域:
分子生物学
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基因工程
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农业科学
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产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2021
·
IF 7.963
Haiyan Wang,Yiming Xie,Yujia Wang,Guosong Lai
The abuse of kanamycin (Kana) in many fields has led to increasing antibiotic pollution problems and serious threats to public health. Therefore, determining how to develop methods to realize the convenient detection of antibiotics in complicated environmental matrices is highly desirable. In this study, we utilized a target biorecognition-triggered hybridization chain reaction (HCR) assembly of a G-quadruplex DNAzyme (G-DNAzyme)-decorated nanotree to develop a novel homogeneous colorimetric biosensing method for the convenient and ultrasensitive detection of Kana antibiotic residues in real samples. Through the designed aptamer-recognition reaction, an Mg 2+ -dependent DNAzyme (MNAzyme) strand can be liberated. Thus, its catalyzed cleavage of the hairpin substrates anchored at a DNA nanowire will cause the assembled formation of an HCR-initiator; this process can be greatly amplified by the exonuclease III-assisted target recycling and the MNAzyme-catalyzed release of another MNAzyme strand. Based on the DNA-nanowire-accelerated HCR assembly of many G-DNAzyme-decorated DNA duplexes on the two sides of the nanowire, a DNA nanotree decorated by numerous G-DNAzymes will form to realize the ultrasensitive colorimetric signal output. Under the optimal conditions, this method exhibited a wide five-order-of-magnitude linear range and a very low detection limit of 28 fg mL −1 . In addition, excellent selectivity, repeatability, and reliability were also demonstrated for this homogeneous bioassay method. These unique features along with its automatic manipulation and low assay cost show promise for practical applications.
研究领域:
分析化学
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生物传感器
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环境科学
·
分子生物学
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DOI
PubMed
高影响因子
TALANTA
·
2022
·
IF 6.556
Lv Yuxiong,Sun Yingying,Liu Wenjie,Yu Jianna,Jing Guoxing,Liu Wen,Xia Huaiyue,Li Dongyan,Li Wenshan
Detection of ultralow concentration of tetracycline (TC) plays a key role in food safety and human health. Herein, we fabricated an enzyme-free dual-amplification assay for sensitive detection of TC in milk. The sensing system ingeniously combined Mg 2+ -dependent DNAzyme (MNAzyme) cleavage and catalytic hairpin assembly (CHA). Through the binding of TC and specific aptamer (Apt), DNA1 was released from the Apt-DNA1 complex. Then the separated DNA1 would hybridize with DNA2 to activate the catalytic activity of MNAzyme, which subsequently cleaved the substrate H0 and generated a new unit to trigger the following CHA reaction between H1 and H2, thereby releasing the G-rich sequence of H1 to induce the formation of G-quadruplex–hemin DNAzyme as a colorimetric signal readout. Under optimal conditions, the absorption intensity exhibited a significant linear correlation with the logarithm of the target TC concentration over a range of 4 orders of magnitude dynamic range from 1 pM to 10 nM. The limit of detection was calculated to be 0.89 pM and the method showed high selectivity for TC. More impressively, the proposed method was employed for TC determination in the milk sample.
研究领域:
分析化学
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食品科学
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生物技术
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分子生物学
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产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Peipei Song,Zhirui Fan,Shuai Sun,Chengye Sun,Jun Wang
In recent years, lead (Pb) contaminated soil has caused irreversible damage to human beings. It is urgent to develop a novel technology for accurate detection of Pb in the soil solution. Herein, a new electrochemical sensor was fabricated. Fe/ZIF-8 was used as the modification material, gold nanoparticles (AuNPs) were electrodeposited, and DNAzyme was applied on the surface as the probe. Under the optimum conditions (DNAzyme concentration of 1 μmol, fixation time of 4 min, incubation time of 17 h and reaction time of 30 min), the detection range was 5×10 −12 ∼ 5×10 −5 M, and the minimum detection limit was 10 −13 M (3δ). Furthermore, the electrochemical sensor demonstrated outstanding anti-interference ability to common cations, anions, organic compounds and other interference factors. After four consecutive tests, the relative standard deviation (RSD) was only 0.39%, and it still displayed excellent reproducibility with 0.69% of RSD. After 20 days, the sensor’s response to Pb 2+ remained at 93.58%. In addition, the sensor could accurately detect Pb 2+ in the actual soil solutions, and the recoveries of the samples ranged from 92% to 109.4%. In conclusion, this electrochemical sensor can specifically detect Pb 2+ in the soil solution with enhanced sensitivity, anti-interference capability and stability, which is of great significance for Pb 2+ detection in the field.
研究领域:
环境科学
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分析化学
·
纳米技术
✓ 已验证
DOI
高影响因子
MICROCHIMICA ACTA
·
2017
·Vol. 184
·期 8
·2941-2948
·
IF 4.58
Han Cong,Li Rongguo,Li Hui,Liu Su,Xu Chenggong,Wang Jingfeng,Wang Yu,Huang Jiadong
The authors describe a label-free electrochemical aptasensor for ultrasensitive and highly specific detection of the antibiotic based on cascade enzymatic recycling couple with DNAzyme amplification. The assay involves two sequential reactions: the first reaction is a λ exonuclease-assisted cyclic digestion reaction triggered by target-aptamer binding. The second reaction is a nicking endonuclease-aided cyclic nicking reaction, which produces a large amount of G-rich nucleic acid segments. These form a G-quadruplex/hemin complex in the presence of K(I) ions and hemin. Because the G-quadruplex/hemin complex acts as a horseradish peroxidase-mimicking DNAzyme with excellent redox activity, the electrochemical signal transduction is accomplished due to the electroreduction of H 2 O 2 . It appears that this work is the first example that cascade enzymatic recycling coupled to DNAzyme amplification is used for antibiotic detection. The aptasensor was applied to the quantitation of kanamycin and gave a response that is linear in the 1 pM to 10 nM kanamycin concentration range, with a detection limit as low as 0.5 pM. The working voltage (vs. Ag/AgCl) at which data can be acquired best is −0.35 V. The assay offers the advantages of remarkably improved sensitivity, use of affordable instrumentation, and simplified operation without the need for electrochemical labeling or addition of labile reagents. Thus, cascade enzymatic recycling coupled to DNAzyme amplification represents a versatile platform for highly sensitive and specific antibiotics detection.
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研究领域:
分析化学
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生物医学工程
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分子生物学
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产品关联
DOI
高影响因子
Food Analytical Methods
·
2014
·Vol. 8
·期 6
·1556-1564
·
IF 1.802
Liu Tao,Zhang Xiao,Hao Jianpeng,Zhu Wenxin,Liu Wei,Zhang Daohong,Wang Jianlong
Herein, we for the first time report an acetylcholinesterase (AChE)-free colorimetric method for the detection of chlorpyrifos (CP), which is based on the oxidation reaction of H 2 O 2 with CP and 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS 2− ) catalyzed by hemin/G-quadruplex DNAzyme. In the absence of CP, ABTS 2− is directly oxidized by H 2 O 2 with hemin/G-quadruplex DNAzyme as a biocatalyst to produce the blue-green-colored free radical anion (ABTS ·− ), accompanied with an obvious UV-visible absorbance at 418 nm. However, the amount of H 2 O 2 used in H 2 O 2 -DNAzyme-ABTS 2− system will be decreased if CP is first reacted with H 2 O 2 , leading to the decrease of the amount of ABTS ·− and a change in the UV-visible absorbance of ABTS ·− at 418 nm. Thus, an indirect dependence relation between CP concentration and the absorbance of ABTS ·− at 418 nm could be constructed and used for CP detection. Under optimal conditions, the detection range of the method is 0.04–1 μg/mL, with a detection limit of 0.01 μg/mL. Application of the method in real juice samples shows good analytical features in terms of recoveries (95–107.5 %), the relative standard deviation (RSD) (0.6–4.7 %), rendering it as an attractive candidate to current methodologies for the determination of CP.
研究领域:
分析化学
·
环境科学
·
食品安全
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产品关联
DOI
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2020
·Vol. 412
·期 27
·7525-7533
·
IF 3.637
Wu Huanan,Wang Shuokang,Li Sam Fong Yau,Bao Qi,Xu Qiyong
Detection of lead(II) (Pb 2+ ) ions in water is important for the protection of human health and environment. The growing demand for onsite detection still faces challenges for sensitive and easy-to-use methods. In this work, a novel surface plasmon resonance (SPR) biosensor based on GR-5 DNAzyme and gold nanoparticles (AuNPs) was developed. Thiolated DNAzyme was immobilized on the gold surface of the sensor chip followed by anchoring the substrate-functionalized AuNPs through the DNAzyme-substrate hybridization. The coupling between the localized surface plasmon (LSP) of AuNPs and the surface plasmon polaritons (SPP) on the gold sensor surface was used to improve the sensitivity. The substrate cleavage in the presence of Pb 2+ ions was catalyzed by DNAzyme, leading to the removal of AuNPs and the diminished LSP-SPP coupling. The optimal detection limit was 80 pM for the sensor fabricated with 1 μM DNAzyme, corresponding to two or three orders of magnitude lower than the toxicity levels of Pb 2+ in drinking water defined by WHO and USEPA. By tuning the surface coverage of DNAzyme, the sensitivity and dynamic range could be controlled. This sensor also featured high selectivity to Pb 2+ ions and simple detection procedure. Successful detection of Pb 2+ ions in groundwater indicates that this method has the prospect in the onsite detection of Pb 2+ ions in water. Given the variety of AuNPs and metal-specific DNAzymes, this detection strategy would lead to the development of more sensitive and versatile heavy metal sensors.
Graphical abstract
研究领域:
生物化学
·
环境科学
·
纳米技术
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产品关联
DOI
PubMed
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2022
·Vol. 414
·期 22
·6581-6590
·
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
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Biosensors-Basel
·
2023
·Vol. 13
·期 1
·118
·
IF 5.4
Yue Guan,Junning Ma,Jing Neng,Bolei Yang,Yan Wang,Fuguo Xing
Zearalenone (ZEN), one of the most frequently occurring mycotoxin contaminants in foods and feeds, poses considerable threat to human and animal health, owing to its acute and chronic toxicities. Thus, rapid and accurate detection of ZEN has attracted broad research interest. In this work, a novel and label-free chemiluminescence aptasensor based on a ZEN aptamer and a G-quadruplex DNAzyme was constructed. It was established on a competitive assay between ZEN and an auxiliary DNA for the aptamer, leading to activation of the G-quadruplex/hemin DNAzyme and subsequent signal amplification by chemiluminescence generation after substrate addition. To maximize the detection sensitivity, numerous key parameters including truncated aptamers were optimized with molecular docking analysis. Upon optimization, our aptasensor exhibited a perfect linear relationship (R2= 0.9996) for ZEN detection in a concentration range of 1–100 ng/mL (3.14–314.10 nM) within 40 min, achieving a detection limit of 2.85 ng/mL (8.95 nM), which was a 6.7-fold improvement over that before optimization. Most importantly, the aptasensor obtained a satisfactory recovery rate of 92.84–137.27% and 84.90–124.24% for ZEN-spiked wheat and maize samples, respectively. Overall, our label-free chemiluminescence aptasensor displayed simplicity, sensitivity, specificity and practicality in real samples, indicating high application prospects in the food supply chain for rapid detection of ZEN.Keywords:chemiluminescence;label-free;aptasensor;DNAzyme;ZEN
研究领域:
分析化学
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食品科学
·
毒理学
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产品关联
DOI
PubMed
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2022
·Vol. 414
·期 14
·4079-4088
·
IF 4.478
Xu Wei,Zhang Yu,Chen Hao,Dong Jinhua,Khan Ranjha,Shen Jianjun,Liu Honglin
Here, we developed a surface-enhanced Raman scattering (SERS) sensor based on functionalized Au@Ag core–shell nanorods (Au@Ag NRs) and cascade DNAzyme amplifier (CSA) for sensitive and accurate determination of microRNA-21 (miRNA-21). The as-prepared SERS nanoprobes were composed of a thiol-modification hairpin probe (HP2)–functionalized Au@Ag NRs and hairpin DNAzyme (HP1-Dz). Compared with original gold nanorods, the silver shell caused an enhancement of plasmonic properties, resulting in a significant enhancement of Raman signals. In the presence of target miRNAs, the hairpin construction of HP1-Dz changed due to DNA/RNA hybridization; subsequently, the DNAzyme-catalyzed cleaving process changed, and the Raman signals of the SERS nanoprobes gradually “turned off” with time elapse because of the dissociation of the Raman reporter from the surface of Au@Ag NRs. Hence, based on this principle, the proposed SERS sensor exhibited good linearity in the range 0.5 fM to 10 nM for miRNA-21 detection with a detection limit (LOD) of 0.5 fM. The proposed SERS platform has potential application in quantitative and precise detection of miRNA-21 in human serum. Graphical abstract
研究领域:
纳米技术
·
分析化学
·
生物传感
·
分子生物学
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生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
·
2025
·
IF 5.1
Mei Xiang,Chengyan Yin,Qiulian Chen,Guonian Zhu,Zhaoxia Chen,Hailiang Li,Ruth Antwi-Baah,Jiangwen Tang,Kunhong Yang,Shuxia Xu
A DNAzyme-based photocatalytic electrochemical biosensor was developed for the label-free detection of uranyl ions (UO 2 2+ ) in water. In this sensing platform, SYBR Green (SG) molecules were embedded in double-stranded DNA (dsDNA), which was cleaved via formed singlet oxygen ( 1 O 2 ) during photosensitization, resulting in a significant decrease in the impedance signal of [Fe (CN) 6 ] 3−/4− . In the presence of UO 2 2+ , the substrate strand was cleaved by the target UO 2 2+ , releasing the SG molecule from the dsDNA, and the photosensitive reaction was turned off. Therefore, UO 2 2+ can be detected based on changes in [Fe(CN) 6 ] 3−/4− electrochemical signals. Such a sensing strategy allowed the detection of UO 2 2+ in the concentration range of 1–1000 nM, with a limit of detection (LOD) of 1.3 × 10 −10 M. The LOD meets the maximum allowable contamination level (1.3 × 10 −7 M) of UO 2 2+ in drinking water set by the US Environmental Protection Agency (EPA). The proposed sensor has been successfully applied for detection of UO 2 2+ in spiked actual water samples with recoveries in the range of 88.0 %–103 %, comparable to those obtained by ICP-MS. The method, which combines photocatalysis with an electrochemical biosensor, significantly improved the sensitivity for UO 2 2+ detection without the need of labeling and additional signal amplification steps. It is also a promising strategy for rapid monitoring of UO 2 2+ in environmental water samples.
研究领域:
环境科学
·
分析化学
·
生物传感技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）