SENSORS AND ACTUATORS B-CHEMICAL
·
2016
·
IF 4.758
Gonge Tang,Cailan Zhao,Jie Gao,Hongliang Tan
It is of great importance to simply and sensitively detect hydrogen sulfide (H 2 S) because of its role in various physiological processes as well as its inherent toxicity. In this work, a colorimetric method for H 2 S detection was developed by employing terbium-G-quadruplex-hemin (Tb/G4-hemin) DNAzyme as a peroxidase mimic, which can catalyze H 2 O 2 -mediated oxidation of 2,2′-azinobis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) to produce radical cation (ABTS + ). Compared with the G4-hemin DNAzyme promoted by K + and Na + , Tb/G4-hemin DNAzyme exhibits a higher catalytic activity. In the presence of Ag + , the peroxidase-like activity of Tb/G4-hemin DNAzyme can be inhibited significantly owing to the disruption of G-quadruplex structure. However, the addition of H 2 S can effectively suppress such negative behavior by competitive binding with Ag + , leading to the recovery of the peroxidase-like activity of Tb/G4-hemin DNAzyme, which can be reflected by an increase in absorbance signal of ABTS + . The absorbance of ABTS + was enhanced linearly with increasing H 2 S concentration from 20 nM to 2 μM. The detection limit for H 2 S is 13 nM, which is much lower than most of previous methods. Moreover, the proposed method possesses the features of simple preparation, easy reproducibility and good biocompatibility. Given the fine performances and striking properties, we believe that the Tb/G4-hemin DNAzyme would have a great promise for analytical applications.
研究领域:
分析化学
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生物化学
·
分子生物学
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DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2022
·
IF 9.221
Jianmei Yang,Qian Bi,Xinmei Song,Ruo Yuan,Yun Xiang
Sensitive and accurate monitoring of amino acid concentration variations plays an important role for diagnosis of diseases at early stage. Here, the aptamer/organometallic receptor-based methodology for label-free and amplified electrochemical determination of phenylalanine , an amino acid, through multi-pedal DNA walker and DNAzyme dual signal enhancement is demonstrated. The binding of the phenylalanine/organometallic receptor complex with the aptamer results in the release of active DNAzyme walking strands to trigger the multi-pedal DNA walkers to move on the surface of electrode. The substrate hairpins are then cyclically cleaved by the DNA walkers to liberate a large number of free G-quadruplexes, which interact with and confine hemin on the electrode via the G-quadruplex/hemin structures. Significantly amplified current signals can therefore be generated by electrochemical reduction of hemin for the sensitive measurement of phenylalanine down to 1.03 μM. Such an aptasensor also has a high selectivity and can monitor phenylalanine in diluted serums, making it a promising alternative for the development of versatile and robust aptamer-based platforms for detection of various amino acids.
研究领域:
生物化学
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分析化学
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医学诊断
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产品关联
DOI
高影响因子
JOURNAL OF APPLIED ELECTROCHEMISTRY
·
2022
·Vol. 52
·期 5
·885-893
·
IF 2.925
Zhao Fei,Xue Wenwen,Zhang Hongfang
Abnormal expression and functioning of microRNAs in the immune system are frequently linked to various cancers. Our previous work demonstrated a universal, label-free, and reliable microRNA detection platform based on the nanochannels-based recognition interface and electrode-based sensing interface. Herein, the strategy of G-quadruplex DNAzyme-catalyzed deposition was introduced into the nanochannels to improve the detection sensitivity of the platform. G-quadruplex DNAzyme could catalyze the oxidation of 4-chloro-1-naphthol to produce insoluble precipitates into the nanochannels which amplified the effect of the hybridization reaction between the capture probe and the target to the mass transport of the redox probe through the recognition interface. Then, a porous carbon nanofibers-modified electrode was applied to further amplify the monitoring sensitivity of the sensing interface to the concentration change of the redox probe methylene blue. Thereby, sensitive electrochemical detection of microRNA-21 was acquired. The biosensing platform exhibited a broad linear range of 100 aM to 1 nM for microRNA-21, with a low detection limit of 40 aM. What is more, the selective and reproducible platform provided an alternative technique for the PCR-free determination of microRNA in serum and tumor cells. Graphical abstract
研究领域:
生物化学
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分子生物学
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癌症研究
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电化学
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DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2021
·
IF 7.46
Lihong Zhou,Yamin Xiong,Hui Wang,Aihong Yin,Xueying Zhang,Huiling Li,Qinghua Fu,Peili Huang
Monitoring copper (Cu) species in bio-samples is critical for the investigation and auxiliary diagnosis of Cu-metabolism disorders. Herein, a target-triggered DNAzyme walker, consisting of Carboxyfluorescein (FAM)-labeled substrates of the Cu-DNAzyme (Cu-Sub) coated gold nanoparticles (AuNPs) ( [email protected] track) and the enzyme chain of the Cu-DNAzyme (Cu-Enzy) functionalized magnetic beads ( [email protected] 3D walking unit), was designed for the sensitive detection of copper species. Upon addition of copper ion (Cu 2+ ), DNAzyme was activated and triggered the walking process, thereby releasing FAM-labeled fragments and recovering fluorescence. When compared with free-running Cu-Enzy or co-conjugated Cu-Enzy on AuNPs walking units, the [email protected] walking unit exhibited a higher cleavage efficiency, shorter detection time (40 min), and a lower limit of detection (LOD = 3 nM). This improved performance was mainly attributed to multivalent interactions between the 3D track and the 3D walking unit which dramatically increased the affinity and cleavage efficiency. Importantly, good accuracy was observed for copper species analysis in clinical serum samples (n = 130), relative to other instrumentation, inductively coupled plasma atomic emission spectrometry (ICP-AES) ( P > 0.01). The serum detection data indicated that total, exchangeable and relative exchangeable Cu variables could serve as potential indicators for the auxiliary diagnosis of Cu-related disorders. Thus, our target-triggered DNAzyme walker provides improved technical support for the in-depth study of clinical Cu metabolic-related diseases.
研究领域:
分析化学
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生物化学
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纳米技术
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临床诊断
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DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2013
·
IF 5.695
Wenjiao Zhou,Xue Gong,Yun Xiang,Ruo Yuan,Yaqin Chai
The employment of DNAzyme probes for visual biodetections has received increasing interest recently due to the simple nature of this type of assay. However, achieving high sensitivity and detecting targets beyond nucleic acids remain two major challenges in DNAzyme-based visual detections. In this work, based on a new quadratic amplification strategy, we developed a sensitive and visual detection method for cytokines by using hairpin aptamer DNAzyme probes. The target cytokine, interferon γ (IFN-γ), associates with the aptamer sequences and unfolds the hairpin structure of the probes, leading to simultaneous recycling of the target IFN-γ (assisted by Bst-polymerase) and the DNA sequences (aided by λ exonuclease) to achieve quadratic amplification. This quadratic amplification results in the generation of numerous peroxidase-mimicking DNAzymes, which cause significantly intensified color change of the probe solution for highly sensitive detection of IFN-γ by the naked eye down to 50 pM. The proposed visual sensing method shows also high selectivity toward the target IFN-γ and can be performed in homogeneous solutions with using completely unmodified, synthetic aptamer DNAzyme probes. These distinct advantages of our developed assay protocol make it a potential platform for detecting various types of biomolecules with careful probe designs.
研究领域:
生物化学
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分析化学
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分子生物学
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生物技术
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产品关联
DOI
PubMed
高影响因子
BIOELECTROCHEMISTRY
·
2024
·
IF 4.8
Linhong Cao,Tianyu Wang,Jingling Xie,Yihua Wang,Yaxin Huang,Sijian Luo,Xiaoting Zhan,Hui Jiang,Liuxin Ran,Xing Jin,Jinbo Liu,Baolin Li
In this study, an innovative electrochemical biosensor was developed for the rapid, specific, and sensitive detection of Acinetobacter baumannii without the need for sample pretreatment. The biosensor utilized an aptamer as a specific capture probe for A. baumannii and employed a self-powered DNAzyme walker cleavage cycle reaction to achieve signal amplification. Upon introduction of the target bacteria, the aptamer captured the bacteria and released the Trigger, activating the DNAzyme to cleave the substrate chain containing methylene blue (MB). This led to the release of MB-labeled DNA fragments from the electrode surface, resulting in a significant decrease in the square wave voltammetry (SWV) signal of MB on the sensing platform. The limit of detection (LOD) for A. baumannii was determined to be 30 CFU/mL, enabling discrimination of the target bacteria from other common clinical isolates. Furthermore, the biosensor’s potential for real sample analysis was demonstrated in cerebrospinal fluid (CSF), showcasing its efficacy and versatility as a biosensing tool with wide-ranging applications in disease diagnosis and bioanalysis.
研究领域:
生物传感技术
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医学诊断
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微生物学
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产品关联
DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2021
·
IF 6.986
Mengmeng Xia,Fu Zhou,Xiuyun Feng,Jiahui Sun,Li Wang,Na Li,Xiayan Wang,Guangfeng Wang
An effective and precise electrochemiluminescence resonance energy transfer (ECL-RET), including the efficient regulation over the proximity of a donor and an acceptor and the reliable stimuli responsive as well as the avoidance of undesirable probes leakage, etc., is significant for the development of an accurate and sensitive ECL detection method; yet, the current literature in documentation involves only a limited range of such ECL-RET systems. Herein, we propose an ECL-RET strategy with dually quenched ultralow background signals and a dual-stimuli responsive, accurate signal output for the ultrasensitive and reliable detection of anatoxin-a (ATX-a). The dual quenching is accomplished by an integrated ECL-RET probe of metal organic frameworks (MOFs) encapsulated into Ru(bpy)32+ (Ru-MOF) (donor) coated with silver nanoparticles (AgNPs) shell (acceptor 1) and close proximity with DNA-ferrocene (Fc) (acceptor 2). Multistimuli responsive DNAzyme facilitated the accurate signal switch by both target ATX-a and hydrogen peroxide (H2O2). Because of the specific recognition of the aptamer toward ATX-a, an intricate design of the DNA sequence enabled the exposure of the Ag+-dependent DNAzyme sequence and H2O2 in situ generated Ag+ triggering a catalytic cleavage reaction to freely release the two ECL-RET energy acceptors, thus switching the ECL signal significantly and achieving ultrasensitive detection. It is noteworthy that AgNPs are key in this ECL-RET strategy, serving both as the gate-keepers for avoiding ECL probes leakage and also the ECL energy acceptors, and mostly importantly serving as the redox substrate for the subsequent DNAzyme catalytic signal switch. The proposed ECL-RET aptasensor for ATX-a detection displayed splendid monitoring performance with a quite low detection limit of 0.00034 mg mL–1. This sensor not only led to the development of a dual-quenching ECL-RET system but also provided meaningful multistimuli responsive ECL biosensing platform construction, which shows a promising application prospect in complicated sample analysis.
研究领域:
分析化学
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生物传感
·
环境科学
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DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2016
·
IF 7.476
Yin-Zhu Wang,Wei Zhao,Pan-Pan Dai,Hai-Jie Lu,Jing-Juan Xu,Jing Pan,Hong-Yuan Chen
Herein, a spatial-resolved electrochemiluminescene (ECL) ratiometry based on a closed biopolar electrode (BPE) is reported for the highly sensitive detection of prostate specific antigen (PSA). [email protected] 3 N 4 NCs as one ECL emitter were firstly coated on the cathode of BPE, while the anode of the BPE served for calibration via another ECL substance, Ru(bpy) 3 2+ . The electroneutrality across the BPE makes the reactions on each pole of BPE electrically coupled. Thus one electrochemical sensing reaction at one pole of BPE could be quantified at both ends. A composite, Pt-PAMAM-DNAzyme was assembled on the surface of cathode via DNA hybridization between probe DNA and PSA aptamer . It acted as an ECL quencher of g-C 3 N 4 via resonance energy transfer (RET) and catalyzing the reduction of O 2 , the co-reactant of g-C 3 N 4 . Meanwhile, it could promote the ECL of Ru(bpy) 3 2+ at anode, since the catalytic reduction of O 2 at the cathode increased the faradiac current flowing through the BPE. Based on this signal composite , an ECL “off-on” phenomenon was observed at the cathode, after Pt-PAMAM-DNAzyme was “peeled off” by PSA. Conversely, at the anode, an “on-off” ECL changing was obtained. Therefore, a sensitive ratiometry for PSA detection was achieved with a linear range from 0.10 to 200 ng/mL. Since the two ECL emitters were physically separated, the ratiometric system was relatively simple and neither optical filters nor spectrometer were required. The strategy combining the ECL ratiometry and BPE broadens the applications of BPE-ECL and shows good perspective in clinical application.
研究领域:
生物分析
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医学检测
·
电化学传感
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DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2024
·
IF 5.7
Mengmeng Wu,Bing Yang,Lu Shi,Qiaorong Tang,Jing Wang,Wei Liu,Baoxin Li,Yan Jin
Background The human immunodeficiency virus (HIV) remains a major worldwide health problem. Nowadays, many methods have been developed for quantitative detecting human immunodeficiency virus DNA (HIV-DNA), such as fluorescence and colorimetry. However, these methods still have the disadvantages of being expensive and requiring professional technicians. Early diagnosis of pathogens is increasingly dependent on portable instruments and simple point-of-care testing (POCT). Therefore, it is meaningful and necessary to develop portable and cheap methods for detecting disease markers. Results In this work, a label-free chemiluminescence (CL) method was developed for detecting HIV-DNA via a handheld luminometer. To achieve label-free target detection, the CL catalyst, G-triplex-hemin DNAzyme (G3-hemin DNAzyme), was in-situ assembled in the presence of HIV-DNA. For improving sensitivity, HIV-DNA induced the cyclic strand displacement reaction (SDR), which can form three G3-hemin DNAzymes in one cycle. So, the chemiluminescence reaction between luminol and H 2 O 2 was highly effectively catalyzed, and the CL intensity was linearly related with the concentration of HIV-DNA in the range of 0.05–10 nM with a detection limit of 29.0 pM. Due to the high specificity of hairpin DNA, single-base mismatch can be discriminated, which ensured the specific detection of HIV-DNA. Significance In-situ formation of G3-hemin DNAzyme led to label-free and selective detection without complex synthesis and functionalization. Therefore, it offers a cheap, selective, sensitive and portable method for detecting disease-related genes, which is promising for POCT of clinical diagnosis in resource-limited settings.
研究领域:
生物医学
·
分子诊断
·
临床检验
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产品关联
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2025
·Vol. 192
·期 6
·1-12
·
IF 5.3
Chen Yafei,Zhang Xuhui,Huang Wanjin,Jin Zhenhuan,Wei Xiaoping,Li Jianping
Atrazine (ATZ) is used extensively, resulting in residues in food and the environment, posing a serious threat to human health. Herein, Cd 0.5 Zn 0.5 S/Ti 3 C 2 photoelectric material was synthesized and immobilized on a FTO electrode as a photoanode. A photoelectrochemical (PEC) aptamer sensor was constructed for the highly sensitive and selective determination of ATZ based on signal amplification via cascade catalysis of CRISPR/Cas12a and G-quadruplex/hemin DNAzyme (G4/hemin DNAzyme). G4/hemin DNAzyme catalyses the oxidation reaction between H 2 O 2 and dopamine (DA) to form polydopamine (PDA) deposit. This process, in turn, inhibits the photocurrent at the photoanode, leading to a decrease in photocurrent. Concurrently, the depletion of DA as an electron donor for the PEC reaction at the photoelectrode further contributes to the decrease in photocurrent. ATZ can hybridize with ATZ aptamer (Apt) in Apt/cDNA to release activation strand (cDNA), which activates the activity of CRISPR/Cas12a and triggers cleavage of G4, causing the cleaving of G4/hemin DNAzyme immobilized on the electrode surface. This process leads to a decrease of G4/hemin DNAzymes amount on the electrode, consequently reducing both the PDA generation and the DA consumption. As a result, the photocurrent is restored. The cascade catalysis of CRISPR/Cas12a and G4/hemin DNAzyme has been demonstrated to result in photocurrent amplification. The photocurrent change was linear with the logarithmic value of ATZ concentration in the range 1.00 × 10 –12 to 1.00 × 10 –5 mol/L. The limit of detection was 3.47 × 10 –13 mol/L. The sensor has been successfully applied to the determination of trace ATZ in environmental and food samples. Graphical abstract
研究领域:
环境科学
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分析化学
·
分子生物学
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产品关联
DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2015
·
IF 6.409
Qian Zhou,Youxiu Lin,Yuping Lin,Qiaohua Wei,Guonan Chen,Dianping Tang
In this work, a sensitive and specific electrochemical biosensor for lead ion (Pb 2+ ) detection was developed by coupling with synergetic catalysis of porous Au–Pd bimetallic nanoparticles and hemin/G-quadruplex-based DNAzyme. In the presence of target Pb 2+ , the substrate strand was cleaved and the enzyme strand was released. Subsequently, G-rich DNA-labeled Au–Pd bimetallic nanoparticle was linked with the released enzyme strand through the helper DNA . Upon addition of hemin , a large number of hemin/G-quadruplex-based DNAzyme molecules were formed on the electrode to serve as nicotinamide adenine dinucleotide hydrogen (NADH) oxidase and peroxidase mimics. DNAzyme could catalyzed the reduction of H 2 O 2 , generated from NADH in the presence of O 2 , to produce an electrochemical signal when using thionine as the electron mediator. Introduction of porors Au–Pd bimetallic nanoparticles could enhance the detectable signal and cause the increase in the sensitivity. Experimental results showed that the variations (∆ I ) in the cathodic peak currents of the biosensor were linearly dependent on target Pb 2+ concentrations from 1.0 pM to 100 nM with a detection limit (LOD) of 0.34 pM. The excellent performance of the sensing platform indicated its promising prospect as a valuable tool for simple and cost-effective Pb 2+ detection in practical application.
研究领域:
生物化学
·
纳米技术
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环境科学
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产品关联
DOI
PubMed
高影响因子
ANALYST
·
2022
·Vol. 147
·期 11
·2575-2581
·
IF 5.227
Xu-Hua Zhao,Xiao-Chun Dai,Ya-Nan Zhou,Han-Xiao Zhang,Xiao-Hua Cui,Xiang Zhai,Bao-Feng Yu,Zhi-Ling Song
In this paper, we developed an amplified fluorescence biosensor for acetylcholinesterase (AChE) activity detection by taking advantage of the mercury ion-mediated Mgzyme (Mg2+-dependent DNAzyme) activity. The catalytic activity of Mgzyme can be inhibited by the formation of T–Hg2+–T base pairs between the Mgzyme and mercury ions. Therefore, the Mgzyme–Hg2+ complex has no activity on a molecular beacon (MB) substrate, which afforded a very weak fluorescence background for this biosensor. After the addition of acetylcholinesterase (AChE), the substrate acetylthiocholine could be hydrolyzed to thiocholine, which has a stronger binding power with mercury ions than T–Hg2+–T base pairs. Therefore, the Mgzyme activity was recovered. The activated Mgzyme could hybridize with the MB substrate and undergo many cleavage cycles, resulting in a significant increase of fluorescence intensity. This biosensor displayed high sensitivity with the detection limit as low as 0.01 mU mL−1. Moreover, this design did not require complex composition and sequence design; thus it is simple and convenient. This biosensor was also applied for the determination of AChE in human blood and showed satisfactory results.
研究领域:
分析化学
·
生物化学
·
生物传感器
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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）