MOLECULES
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2021
·Vol. 26
·期 16
·5016
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IF 4.412
Yufen Lai,Mengyan Li,Xiaofei Liao,Li Zou
Abnormal levels of reduced glutathione (GSH) and glutathione reductase (GR) are usually related to a variety of diseases, so it is of great significance to determine the GSH concentration and GR activity. We herein develop a smartphone-assisted colorimetric biosensor for the detection of GSH and GR activity in human serum and mouse liver using hemin/G-quadruplex DNAzyme. Firstly, an obvious color change from colorless to green can be observed, owing to the high peroxidase-like activity of hemin/G-quadruplex DNAzyme toward 2,2′-azino-bis(3-ethylbenzothiozoline-6-sulfonic acid) (ABTS). With the addition of GSH or GR, the H2O2-mediated oxidation of ABTS catalyzed by hemin/G-quadruplex DNAzyme is significantly inhibited, resulting in remarkable color fading. Therefore, the detection of GSH and GR activity can be achieved by observing the color transition or measuring the absorbance at 420 nm. The detection limit was estimated to be as low as 0.1 μM and 10 μU/mL for GSH and GR, respectively. More interestingly, the RGB values of the sensing system can be identified by the smartphone application (APP, color collect), which makes it an ideal format for on-site determination and point-of-care testing (POCT). In addition, the proposed method shows excellent selectivity and acceptable applicability for the determination of GSH concentration and GR activity in human serum samples and mouse liver tissues, which might hold great application potential in clinical diagnosis and drug screening.Keywords:smartphone;colorimetric assay;glutathione;glutathione reductase;hemin/G-quadruplex DNAzyme
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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DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
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2017
·
IF 7.78
Shuai Chen,Pin Liu,Kewen Su,Xuan Li,Zhen Qin,Wei Xu,Jun Chen,Chaorui Li,Jingfu Qiu
In this work, novel octahedral Cu 2 O-Au nanocomposites were synthesized and first applied in an electrochemical aptasensor to detect thrombin (TB) with the aid of a DNAzyme for signal amplification . The octahedral Cu 2 O-Au nanocomposites have not only simultaneously served as signal amplifying molecules but have also been utilized as an ideal loading platform to immobilize a large number of electroactive substances and recognition probes. Gold nanoparticles (AuNPs) were grown directly on the surface of the octahedral Cu 2 O nanocrystals , and the Cu 2 O-Au nanocomposites obtained had the advantages of large surface areas and excellent biocompatibilities. The hemin/G-quadruplex, which was formed by intercalating hemin into the amino terminated thrombin binding aptamer (NH 2 -TBA), and the electroactive toluidine blue (Tb) were immobilized onto the Cu 2 O-Au nanocomposite surfaces through a stable Au-N bond. AuNPs, Cu 2 O and hemin/G-quadruplex co-catalyse the H 2 O 2 in the working buffer to promote the electron transfer of Tb as a multiple signal amplification strategy in order to improve the performance of the electrochemical aptasensor. Under optimal conditions, the designed aptasensor exhibited sensitive detection of TB from 100 fM to 20 nM with a lower detection limit of 23fM. This proposed aptasensor exhibited good sensitivity, high specificity and acceptable reproducibility and could be widely applied in bioassay analysis.
研究领域:
生物化学
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纳米医学
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分析化学
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DOI
PubMed
高影响因子
ANALYST
·
2013
·Vol. 138
·期 12
·3409-3415
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IF 3.969
Xiaomeng Meng,Yunlei Zhou,Qianjin Liang,Xiangjin Qu,Qingqing Yang,Huanshun Yin,Shiyun Ai
A simple and novel microRNA (miRNA) biosensor was developed using DNA-Au bio bar code (DNA-Au) and G-quadruplex-based DNAenzyme. DNA-Au increased the amount of miRNA-21 participating in hybridization. Hemin/G-quadruplex DNAenzyme significantly improved the catalysis of H2O2 by oxidation of hydroquinone, resulting in an obvious reduction current of benzoquinone for miRNA-21 indirect detection. Under optimum conditions, the linear relationship between miRNA-21 concentration and reduction response was obtained with the detection limit of 0.006 pM, which showed a good sensitivity. Besides, selectivity of the biosensor was investigated by detecting the base mismatched miRNAs. This proposed method was further applied to detect miRNA-21 extracted from human hepatocarcinoma BEL-7402 cells and human mastocarcinoma MCF-7 cells. The influence of bisphenol A (BPA) on the expression of miRNA-21 in cells was also investigated. The biosensor performs well in practical applications, which suggests it may provide a new platform for gene diagnosis.
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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癌症研究
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DOI
PubMed
高影响因子
FOOD CONTROL
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2024
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IF 5.6
Xiaowei Chen,Yujun Feng,Yuanyuan Wang,Xin Yang,Xingping Zhang,Hualin Yang,Yu Zhou
With the gradual increase of oxytetracycline (OTC) residue in the environment, it is particularly important to establish a sensitive and efficient method to detect OTC. In this work, a novel colorimetric and fluorescence dual-mode detection method based on hemin/G-quadruplex (hemin/G4) DNAzyme and zeolitic imidazolate framework-8 (ZIF-8) is developed. OTC can compete with G4 to bind hemin to reduce the amount of hemin/G4. Thus, the oxidation of 3, 3′, 5, 5′-tetramethylbenzidine (TMB) to blue color by hemin/G4 is inhibited. In addition, the OTC or OTC-hemin can be aggregated with the help of ZIF-8 to produce strong green fluorescence due to the aggregation-induced emission (AIE) effect. In colorimetric and fluorescence mode, the linear ranges of the new method are 0.375–18 μM and 0–52.5 μM, with a limit of detection (LOD) of 0.116 μM and 0.040 μM, respectively. Besides, this new method has a good selectivity and recovery rate in the detection of real samples. Therefore, the method can be used for the efficient and sensitive detection of OTC.
研究领域:
分析化学
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环境科学
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生物技术
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DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2019
·
IF 6.393
Ting Bao,Meiqi Wen,Wei Wen,Xiuhua Zhang,Shengfu Wang
In this work, a novel electrochemical biosensor was constructed for ultrasensitive interferon-gamma (IFN-γ) detection based on [email protected] imidazolate framework-8 hybrids anchored gold nanoclusters ( [email protected] ) and hemin/G-quadruplex DNAzyme decorated layered-branched hybridization chain reaction (LB-HCR). The two-dimensional [email protected] hybrids were utilized as template to anchor AuNCs through a sequential deposition method. On the [email protected] platform, an improved and efficient LB-HCR pattern was designed on the strength of traditional HCR with the cascade-like assembly of four hairpins. In which, HP1 and HP2 participated in traditional HCR process to form long double-helix DNA, AD1 and AD2 assembled alternately to facilitate the layerly chain-branching growth of DNA nanostructures. The target-triggered LB-HCR resulted in the generation of dendritic DNA nanostructures integrated with numerous in-situ formed hemin/G quadruplex DNAzyme as amplifying labels, which catalyzed the reduction of H 2 O 2 with thionine acted as the electron mediator to realize amplified signal output. This multiple-amplified strategy exhibited good analytical performance towards IFN-γ with a wide linear range form 1 fM to 50 pM and a low detection limit of 0.6 fM, holding promising application in disease diagnosis and monitoring.
研究领域:
生物传感器
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电化学
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纳米技术
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分析化学
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分子诊断
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产品关联
DOI
高影响因子
Analytical Methods
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2017
·Vol. 10
·期 1
·51-58
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IF 1.9
Xiao-Li Du,Tian-Fang Kang,Li-Ping Lu,Shui-Yuan Cheng
A novel electrochemiluminescence (ECL) biosensor based on CdSe@CdS quantum dots (QDs) functionalized MoS2 modified electrode was developed for sensitive detection of Pb(II) using HRP-mimicking DNAzyme biocatalytic precipitation (BCP) for ECL signal quenching. Polycationic poly(diallyldimethylammonium chloride) (PDDA) and negatively charged QDs were adsorbed on the surface of MoS2, in sequence, to form the MoS2–QDs composites, which were employed as a matrix for the immobilization of the G-rich DNA strand, i.e., T30695. The MoS2–QDs were characterized by UV-vis absorption spectroscopy, fluorescence spectroscopy, energy dispersive spectrometry, transmission electron microscopy, and field emission scanning electron microscopy. CdSe@CdS QDs can produce an ECL signal using 0.1 M K2S2O8 as a co-reactant. T30695 can combine with Pb(II) ions to form a stable parallel G-quadruplex. The G-quadruplex can further combine with hemin to form DNAzyme, which can catalyze H2O2 and oxidize 4-chloro-1-naphthol (4-CN) to produce an insoluble precipitation of benzo-4-chlorohexadienone on the surface of the sensor. When the concentration of Pb(II) in the solution was increased, more of DNAzyme was generated and subsequently more 4-CN molecules were oxidized catalytically, leading to a decrease of the ECL signal. Using this quenching strategy, the ECL signal of the biosensor was linearly dependent on the logarithm of the Pb(II) concentration ranging from 1.0 × 10−15 to 1.0 × 10−11 M with a detection limit of 0.98 f M. The stability and selectivity of the sensor were also investigated. The sensor was applied in the determination of Pb(II) in the real water samples and satisfactory results were obtained.
研究领域:
分析化学
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环境科学
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纳米技术
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生物传感器
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DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
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2014
·
IF 6.451
Hao Wu,Kai Zhang,Yaling Liu,Hongyong Wang,Jun Wu,Feifan Zhu,Pei Zou
In this work, a new binding-induced and label-free colorimetric method for protein detection has been developed on the basis of an autonomous assembly of hemin/G-quadruplex DNAzyme amplification strategy. The system consists of two proximity probes carrying two aptamer sequences as recognition elements for target, and two hairpin structures include three-fourths and one-fourth of the G-quadruplex sequences in inactive configuration as functional elements. In the presence of target protein, two proximity probes bind to the protein simultaneously, forming a stable DNA–protein complex. Then the complex triggers an autonomous cross-opening of the two functional hairpin structures, leading to the formation of numerous hemin/G-quadruplex DNAzymes. The resulting DNAzymes catalyze the oxidation of colorless 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS 2− ) to the green-colored ABTS •− with the presence of H 2 O 2 , thus providing the amplified colorimetric detection of target. Using human α-thrombin as the protein target, this binding-induced DNAzyme amplification colorimetric method affords high sensitivity with a detection limit of 1.9 pM. Furthermore, this method might be further extended to sensitive detection of other proteins by simply replacing recognition elements of proximity probes.
研究领域:
生物化学
·
分析化学
·
生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子