SENSORS AND ACTUATORS B-CHEMICAL
·
2020
·
IF 7.1
Yuqiang Hu,Zhen Zhang,Weicong Ye,Wei Zhang,Minghao Hu,Wenqian Yuan,Hongbo Wang,Xianjin Xiao,Tongbo Wu
Human apurinic/apyrimidinic endonuclease 1 (APE1) plays a crucial role in DNA repair and gene regulation. The abnormal variations of the concentration of APE1 in the human blood and tissue cells are highly correlated to various diseases. Thus, APE1 can be used as a biomarker to aid clinical diagnosis of diseases. Detection of APE1 activity with high sensitivity and selectivity simultaneously is difficult to achieve. Here we provide a DNA structure-mediated fluorescent biosensor to solve the above problem. Upon the existence of APE1, the apurinic/apyrimidinic site will be cleaved, and the terminal structure of the hairpin DNA substrate will change. Then the terminal deoxynucleotidyl transferase and endonuclease IV could provide dual fluorescent signal amplification. Through the ingenious structure design of the biosensor, we have improved the reactivity of APE1 and minimized the interference of other enzymes. The results indicate that the detection limit for APE1 is as low as 1.7 × 10 −6 U/mL. The biosensor has been successfully applied to the detection of APE1 in real biological samples and the screening of APE1 inhibitors.
研究领域:
生物化学
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分子生物学
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医学诊断
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DOI
高影响因子
TALANTA
·
2021
·
IF 6.057
Jinying Liu,Jiabao Zhang,Yue Zhang,Yan Wang,Mengke Wang,Ziwen Li,Guannan Wang,Xingguang Su
In this paper, we proposed a dual-signal fluorometric and colorimetric system based on silicon quantum dots (SiQDs) and 4-nitrophenol (4-NP) for pH and urease sensing. SiQDs with fluorescence emission of 460 nm were prepared via aqueous-phase synthesis. As the pH of the system gradually increased, the absorption band of 4-NP at 400 nm increased and a color reaction from colorless to yellow occurred. The absorption of 4-NP overlapped quiet well with the fluorescence excitation spectrum of SiQDs, which can effectively quench the fluorescence of SiQDs. Therefore, the change of fluorescence and absorption intensities could be used to quantify pH value. The fluorometric and colorimetric pH-sensing systems both exhibited a linear respond to pH ranging from 6.0 to 7.8 with an interval of 0.2 pH unit. Urease could specifically hydrolyze urea to generate carbon dioxide and ammonia, causing an obvious increase of the pH value. Thus, urease could also be detected quantitatively by the above dual-signal pH sensing system. The linear ranges of the fluorometric and colorimetric methods for urease detection were both 2–40 U L-1. The limits of detection were 1.67 and 1.07 U L-1, respectively. More importantly, this established dual-signal system has been successfully exploited in the detection of urease in real samples with satisfactory recoveries. Compared with other traditional single-signal assay strategies, the results obtained by dual-signal methods are more accurate and reliable.
研究领域:
分析化学
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生物化学
·
纳米技术
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DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 12
·1-7
·
IF 5.479
Zhao Xian-En,Zuo Ya-Nan,Qu Xiaoqing,Sun Jing,Liu Lingyuan,Zhu Shuyun
The authors describe novel colorimetric assays for tyrosinase (TYR) and catalase (CAT) based on the substrate-triggered decomposition of MnO 2 nanosheets (NSs). The MnO 2 NSs can act as oxidase mimics that catalyze the oxidation of the substrate tetramethylbenzidine (TMB) to form a blue dye with an absorption maximum at 652 nm. The oxidase-mimicking activity of the MnO 2 NSs is inhibited by dopamine (DA)/hydrogen peroxide (H 2 O 2 ) due to their decomposition of the MnO 2 NSs. TYR catalyzes the oxidation of DA while CAT can decompose H 2 O 2 into water and oxygen. Therefore, the oxidase-mimicking activity of MnO 2 NSs is restored in the presence of both enzymes and their substrates. Based on the competitive consumption of substrates between enzymes and MnO 2 NSs, a colorimetric method for determination of enzyme activity and its substrate is developed. The detection limits for TYR and CAT are 6 mU·mL −1 and 33 mU·mL −1 , respectively.
A colorimetric method for monitoring enzyme activity and its substrate is described. It is based on the substrate-inhibited oxidase-mimicking activity of MnO 2 nanosheets.
研究领域:
生物化学
·
分析化学
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DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2016
·
IF 7.476
Cong Tang,Zhaosheng Qian,Yuanyuan Huang,Jiamin Xu,Hang Ao,Meizhi Zhao,Jin Zhou,Jianrong Chen,Hui Feng
A convenient, reliable and highly sensitive assay for alkaline phosphatase (ALP) activity in the real-time manner is developed based on β-cyclodextrin-modified carbon quantum dots (β-CD-CQDs) nanoprobe through specific host-guest recognition. Carbon quantum dots were first functionalized with 3-aminophenyl boronic acid to produce boronic acid-functionalized CQDs, and then further modified with hydropropyl β-cyclodextrins (β-CD) through B-O bonds to form β-CD-CQDs nanoprobe. p -Nitrophenol phosphate disodium salt is used as the substrate of ALP, and can hydrolyze to p -nitrophenol under the catalysis of ALP. The resulting p -nitrophenol can enter the cavity of β-CD moiety in the nanoprobe due to their specific host-guest recognition, where photoinduced electron transfer process between p -nitrophenol and CQDs takes place to efficiently quench the fluorescence of the probe. The correlation between quenched fluorescence and ALP level can be used to establish quantitative evaluation of ALP activity in a broad range from 3.4 to 100.0 U/L with the detection limit of 0.9 U/L. This assay shows a high sensitivity to ALP even in the presence of a very high concentration of glucose. This study demonstrates a good electron donor/acceptor pair, which can be used to design general detection strategy through PET process, and also broadens the application of host-guest recognition for enzymes detection in clinical practice.
研究领域:
生物化学
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医学检验
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纳米生物学
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DOI
高影响因子
BIOELECTROCHEMISTRY
·
2025
·
IF 4.5
Yun Zhang,Liang Gao,Zhe Shi,Qiong Wu,Xiangmin Miao
Sensitive telomerase activity detection becomes particularly significance since the important value of it in early cancer diagnosis as a potential biomarker. Herein, we developed a paper-based analytical devices (PADs) for telomerase activity detection, using positively charged Au@luminol nanoparticles ((+)Au@luminol NPs) as electrochemiluminescence (ECL) signal probe coupling with hybridization chain reaction (HCR) and CRISPR/Cas12a dual signal amplification. Firstly, the initial strong ECL signal was obtained based on the electrostatic adsorption of (+)Au@luminol NPs onto the surface of HCR double-stranded hybrid aggregates. In the presence of telomerase, the primer was efficiently elongated with telomeric repeats of (TTAGGG) n to release activator DNA and trigger the CRISPR/Cas12a, which can prevent the happen of HCR and the adsorption of (+)Au@luminol NPs through cleaving the capture probe on the electrode surface, such results directly inducing the decrease of the ECL signal that was proportional to telomerase concentration, due to the efficient signal amplification of HCR and CRISPR/Cas12a, a low detection limit of 2.3 cells/mL for telomerase could be detected. Moreover, the sensor realized the effective application for telomerase extracts analysis in human serum samples, making it possess potential application value for telomerase activity assays in cancer diagnostics.
研究领域:
生物医学工程
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分子诊断学
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癌症早期诊断
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DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2023
·
IF 8.2
Liangqiang Chen,Wanqiu Huang,Mengdi Hao,Fan Yang,Hao Shen,Shaoning Yu,Li Wang
α-Amylase plays a significant part in fermentation and the food industry, as this enzyme effectively regulates the content of different sugars in brewing systems and affects the yield and quality of alcoholic beverages. Nevertheless, current strategies suffer from unsatisfactory sensitivity and are time-consuming or are indirect methods which demand the assistance of tool enzymes or inhibitors. Therefore, they are unsuitable for the low bioactivity and non-invasive detection of α-amylase in fermentation samples. Rapid, sensitive, facile, and direct detection method of this protein remains challenging in actual applications. In this work, a nanozyme-based α-amylase assay was constructed. The colorimetric assay used the interaction between α-amylase and γ-cyclodextrin (γ-CD) which crosslinks MOF-919-NH 2 . The determination mechanism bases on the hydrolysis of γ-CD by α-amylase, resulting in increased peroxidase-like bioactivity of the released MOF nanozyme. The detection limit was 0.12 U L −1 with a wide linear range (0–200 U L −1 ) and excellent selectivity. Additionally, the proposed detection method was successfully utilized in distilled yeasts to verify analytical capability in fermentation samples. The exploration of this nanozyme-based assay not only provides a convenient and effective strategy for enzyme activity determination in food industry, but also has promotion significance in clinical diagnosis and pharmaceutical production.
研究领域:
食品科学
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分析化学
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生物技术
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酶学
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DOI
PubMed
高影响因子
JOURNAL OF SEPARATION SCIENCE
·
2013
·Vol. 36
·期 16
·2691-2697
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IF 2.591
Haiyan Zhao,Zilin Chen
An electrophoretically mediated microanalysis method with partial filling technique was developed for screening aromatase inhibitors in traditional Chinese medicine. The in-capillary enzymatic reaction was performed in 20 mM sodium phosphate buffer (pH 7.4), and sodium phosphate buffer (20 mM, pH 8.0) was used as a background electrolyte. A long plug of coenzyme reduced β-nicotinamide adenine dinucleotide 2′-phosphate hydrate dissolved in the reaction buffer was hydrodynamically injected into a fused silica capillary followed by the injection of reaction buffer, enzyme, and substrate solution. The reaction was initiated with a voltage of 5 kV applied to the capillary for 40 s. The voltage was turned off for 20 min to increase the product amount and again turned on at a constant voltage of 20 kV to separate all the components. Direct detection was performed at 260 nm. The enzyme activity was directly assayed by measuring the peak area of the produced β-nicotinamide adenine dinucleotide phosphate and the decreased peak area indicated the aromatase inhibition. Using the Lineweaver–Burk equation, the Michaelis–Menten constant was calculated to be 50 ± 4.5 nM. The method was applied to the screening of aromatase inhibitors from 15 natural products. Seven compounds were found to have potent AR inhibitory activity.
研究领域:
药理学
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分析化学
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中医药学
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DOI
PubMed
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2024
·Vol. 40
·期 2
·320-325
·
IF 3.1
Zhu Tang Jiayao,Yuan Xiang,Mao Guojiang,Wei Lin,Xiao Lehui
Acid phosphatase (ACP) is a ubiquitous phosphatase in living organisms. The abnormal variation of ACP is related to various diseases. Herein, we propose a colorimetric method based on CeO 2 -modified gold core shell nanoparticles (Au@CeO 2 NPs) to analyze ACP activity with high sensitivity and specificity. In this design, 2-phospho- L -ascorbic acid trisodium salt (AAP) is dephosphorylated by ACP and produces reductive ascorbic acid (AA), which makes the CeO 2 shell decomposition. A remarkable blue shift of localized surface plasmon resonance peak (LSPR, from yellow to green) along with the scattering intensity ratio changes from individual Au@CeO 2 NPs are observed. ACP activity can be quantified by calculating the ratio changes of individual Au@CeO 2 NPs. This assay reveals limit of detection (LOD) of 0.044 mU/mL and the linear range of 0.05–5.0 mU/mL, which are much lower than most of spectroscopic measurements in bulk solution. Furthermore, the recovery measurements in real samples are satisfactory and the capacity for practical application is demonstrated. As a consequence, Au@CeO 2 NPs used in this assay will find new applications for the ultrasensitive detection of enzyme activity.
研究领域:
生物分析化学
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纳米技术
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酶学
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生物传感器
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生物医学诊断
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DOI
高影响因子
Journal of Materials Chemistry C
·
2017
·Vol. 5
·期 11
·2826-2832
·
IF 5.256
Hang Ao,Hui Feng,Xiaolu Huang,Meizhi Zhao,Zhaosheng Qian
Dynamic covalent B–O bonds are introduced to the design of a reversible fluorescence nanoswitch in response to the external stimulus of pH. This nanoswitch is based on a phenylboronic acid functionalized carbon quantum dot (PBA–CQD) nanoprobe, and constructed with reference to the two facts that the PBA–CQD probe can bind to p-nitrophenol to form a non-fluorescent conjugate via B–O bonds, and that the making and breaking of the B–O bonds between them can be controlled by pH changes. Excellent reversibility of this nanoswitch is illustrated by switching of the pH from 4 to 8. The reaction between the PBA–CQD nanoprobe and the p-nitrophenol resulting in switching off the fluorescence is further utilized to design a general detection strategy for enzyme activity when substrates that can generate p-nitrophenol through enzymatic reactions are chosen. The feasibility of the detection strategy is qualitatively assessed using α-glucosidase and β-galactosidase, and its practicability to quantitatively monitor enzyme activity is also demonstrated by taking α-glucosidase as an example. The detection limit of this method can be as low as 0.33 U L−1, which is much lower than those reported previously and is sufficiently low to be capable of α-glucosidase level detection in practical human samples. This study demonstrates excellent usability of dynamic covalent B–O bonds in the design of reversible switches and in the general detection of enzyme activity, and provides a sensitive, real-time assay for α-glucosidase based on carbon quantum dots.
研究领域:
分析化学
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生物医学工程
·
酶学
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产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2022
·Vol. 189
·期 4
·1-5
·
IF 6.408
Tian Dazhi,Xiang Wen,Wang Hao,Jiang Wentao,Li Ting,Yang Minghui
B-doped core–shell Fe@BC nanozyme was synthesized. The peroxidase (POD) like activity of Fe@BC nanozyme was studied and utilized for detecting the activity of alanine aminotransferase (ALT). In the presence of ALT as well as ALT co-substrates l -alanine and α-ketoglutarate, l -glutamate is generated. The following catalytic oxidation of l -glutamate by glutamate oxidase leads to the generation of H 2 O 2 . The POD-like activity of Fe@BC can oxidize 3,3′,5,5′-tetramethylbenzidine (TMB) to oxTMB in the presence of H 2 O 2 , generating a blue-colored compound. Through the detection of the amount of H 2 O 2 generated, ALT activity can be determined through measuring the absorbance intensity variation at 450 nm. The limit of detection of the assay is 4 U/L, with a linear range from 10 to 1000 U/L. For human serum samples, the ALT levels determined by our assay are comparable to those determined by the hospital with a correlation coefficient of 0.991, demonstrating the reliability of our assay results. Graphical abstract
研究领域:
生物化学
·
医学诊断
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产品关联
DOI
PubMed
高影响因子
TALANTA
·
2023
·
IF 6.1
Dan Luo,Zaiqiong Liu,Aiwen Su,Yanli Zhang,Hongbin Wang,Lijuan Yang,Wenrong Yang,Pengfei Pang
T4 polynucleotide kinase (T4 PNK) is an important DNA repair-related enzyme that plays a crucial role in DNA recombination, replication and damage repair. Herein, an electrochemical biosensor was developed for detection of T4 PNK activity and inhibitor screening based on supramolecular host–guest recognition between phosphate pillar (Dumitrache and McKinnon, 2017) [5] arene (PP5) and methylene blue (MB). The water-soluble PP5 employed as the host for complexation of MB guest molecules. The substrate DNA with 5′-hydroxyl group was first self-assembled on the gold electrode surface through the chemical adsorption of the thiol group , which was phosphorylated in the presence of T4 PNK and adenosine triphosphate (ATP). TiO 2 served as a bridge to link phosphorylated DNA and PP5 via the robust phosphate-Ti 4+ -phosphate chemistry . The immobilized PP5 captured the MB on electrode surface via the supramolecular host–guest recognition interaction, resulting in an enhanced electrochemical response signal. The electrochemical signal is proportional to the T4 PNK concentration in the range of 2 × 10 −4 to 5 U mL −1 with a detection limit of 1 × 10 −4 U mL −1 . It was also successfully used for PNK inhibitor screening and PNK activity assay in HeLa cell lysates sample. The proposed strategy provides a novel sensing platform for kinase activity assay and inhibitor screening, holding a great potential in clinical diagnostics, inhibitor screening, and nucleotide kinase-target drug discovery.
研究领域:
生物化学
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分子生物学
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分析化学
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DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Jin Li,Xiao-Peng Liu,Wen-Qi Ye,Zhang-Run Xu
Alkaline phosphatase (ALP), as a crucial enzyme involved in many physiological activities, is always used as one of the significant biomarkers in clinical diagnosis. Herein, a novel, simple, and effective photothermal quantitative method based on the etching of MnO 2 -coated gold nanoparticles ( [email protected] 2 NPs) was established for ALP activity assay with a household thermometer-based visual readout. The photothermal effect of [email protected] 2 NPs is much higher than that of MnO 2 NPs or Au NPs. The MnO 2 shell of [email protected] 2 NPs can be etched by ascorbic acid , a product of ALP-catalyzed hydrolysis of 2-phospho- l -ascorbic acid. With the etching of [email protected] 2 NPs, the photothermal conversion efficiency decreased gradually, causing the decrease of the temperature increment of the solutions by degrees. A household thermometer, instead of large-scale and professional instruments, was used as a signal reader to realize the visual quantitative detection. The photothermal platform was used successfully for the determination of ALP with a wide linear range from 2.0 to 50 U/L and a detection limit as low as 0.75 U/L. Moreover, the inhibition efficiency of sodium vanadate for ALP activity was investigated, proving the photothermal quantitative method will be a potential platform for screening enzyme inhibitors . Such a sensitive, facile, and low-cost sensing assay provides a new prospect to develop platforms for point-of-care testing.
研究领域:
生物化学
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纳米技术
·
分析化学
·
临床诊断
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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）