SENSORS AND ACTUATORS B-CHEMICAL
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2018
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IF 5.667
Xiang Ran,Zhen Liu,Zhenzhen Wang,Fang Pu,Jinsong Ren,Xiaogang Qu
High sensitive detection and monitoring of miRNAs in living cells have obtained considerable attention for clinical diagnosis of diseases. However, there are still enormous challenges for developing new method of quantification of miRNA in vivo. Herein, an intelligent MnO 2 -carried catalytic DNA machine (MCDM) was constructed for direct visualization of MicroRNAs in vivo with high selectivity and extremely low detection limit. MnO 2 nanosheets were used as a degradable carrier to introduce the DNA machine into cells. Benefiting from the enhanced permeability and retention (EPR) effect, the MnO 2 -carried probes could accumulate in tumor tissue, realizing a direct visualization of low concentration of miR-21 in the tumor of living animals in situ.
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
Materials
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2018
·Vol. 11
·期 12
·2408
·
IF 2.467
Jingjing Zhang,Jialun Han,Shehong Feng,Chaoqun Niu,Chen Liu,Jie Du,Yong Chen
In this study, a target recycled amplification, background signal suppression, label-free fluorescent, enzyme-free deoxyribonucleic acid (DNA) machine was developed for the detection of adenosine triphosphate (ATP) in human urine. ATP and DNA fuel strands (FS) were found to trigger the operation of the DNA machine and lead to the cyclic multiplexing of ATP and the release of single stranded (SS) DNA. Double-stranded DNA (dsDNA) was formed on graphene oxide (GO) from the combination of SS DNA and complementary strands (CS′). These double strands then detached from the surface of the GO and in the process interacted with PicoGreen dye resulting in amplifying fluorescence intensity. The results revealed that the detection range of the DNA machine is from 100 to 600 nM (R2= 0.99108) with a limit of detection (LOD) of 127.9 pM. A DNA machine circuit and AND-NOT-AND-OR logic gates were successfully constructed, and the strategy was used to detect ATP in human urine. With the advantage of target recycling amplification and GO suppressing background signal without fluorescent label and enzyme, this developed strategy has great potential for sensitive detection of different proteins and small molecules.
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
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2017
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IF 5.401
Xiao Fang Zhang,Na Li,Yu Ling,Li Tang,Nian Bing Li,Hong Qun Luo
As one of the DNA damage repair enzymes, uracil-DNA glycosylase (UDG) plays an important role in maintaining genomic integrity. By linked bridge hybridizing-induced split G-quadruplex (SQ), we demonstrate here the construction of a simple and sensitive DNA machine for the detection of UDG activity. The satisfactory split G-quadruplex sequences (SQS) were successfully selected to be the ingredients of SQ formation. In this work, UDG recognized and removed the uracil bases from the stem of hairpin DNA (HP). And then, HP with a low melting temperature hybridized with designed SQS, forming a three-way DNA structure with an SQ. With the addition of Thioflavin T, a dramatical enhancement of fluorescence intensity was presented due to the G-quadruplex/Thioflavin T complex formation. The detection limit was as low as 7.8 × 10 −3 U/mL. And we also successfully investigated the performance of UDG activity in the HeLa cell lysate. This optical DNA machine with the merits of being simple, rapid, and economical was flexibly suitable for not only active UDG assay but also diverse target detection by adjusting the recognition region of the HP.
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
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2018
·
IF 5.667
Xiao Fang Zhang,Na Li,Yu Ling,Nian Bing Li,Hong Qun Luo
Since uracil-DNA glycosylase (UDG) is closely related to some human diseases, monitoring and detection of UDG activity have great significance in its clinic diagnosis and functional study. Here we demonstrate a sensitive cascade multi-amplification fluorescence strategy for the active UDG assay with the help of exonuclease III (Exo III). Under the cleavage reaction of UDG, the double-stranded DNA containing peculiar uracil bases separated into two dissociative single-stranded DNA, which separately hybridized with two cyclic hairpin probes to launch the Exo III-assisted dual cycles. The hairpin DNA modified with fluorophore and quenching group was employed as the signal probe. After the dual cycles, countless same short DNA fragments were generated to hybridize with signal probes, initiating a new Exo III-assisted cyclic amplification and releasing numerous single-stranded DNA which carried only fluorophores. Thus, the fluorescence intensity of the detection system was enhanced. This study obtained the detection limit as low as 2.4 × 10 −4 U/mL for detecting the UDG activity. And it performed satisfactory selectivity and well practical applicability by analysis of the HeLa cell lysate, providing a potential method for clinic diagnosis and functional study of UDG activity.
研究领域:
生物化学
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分子生物学
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临床诊断
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DOI
高影响因子
ELECTROANALYSIS
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2022
·Vol. 35
·期 4
·e202200330
·
IF 3.077
Ting Huang,Wenxing Zhang,Guobing Wie,Nian Hong,Mei Wang,Qiqi Fan,Qiangqiang Yu,Fusheng Liao,Hao Fan
Herein, a reagentless electrochemical DNA sensor based on a self-powered DNA machine for detecting survivin mRNA in cells is developed. The metal-organic framework (MOFs) loaded with DNAzyme cofactors (Mn 2+ ) is coated on PTFE rods on the Au surface and assembled with the DNA walker, overcoming the complexity of adding metal ions from the external environment. In addition, the orbital chain is modified by a synthetic bisferrocene signal marker, which further enables signal amplification. Under optimal conditions, the sensor exhibits a range from 1×10 −14 mol/L to 1×10 −8 mol/L with a detection limit (S/N=3) of 1.28 fM.
研究领域:
生物传感技术
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分子生物学
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纳米材料科学
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DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2017
·
IF 5.401
Xiao Fang Zhang,Na Li,Cui Ye,Jia Yu Liang,Nian Bing Li,Hong Qun Luo
Uracil-DNA glycosylase (UDG), one of the base-excision repair enzymes, is closely relevant for the diseases of the organism. Here, we proposed a resonance Rayleigh scattering (RRS) strategy for sensitively detecting the active UDG based on a dual amplification DNA machine without label under the catalysis of exonuclease III (Exo III). In our study, a double-stranded DNA complex S1-S2 containing triggers and peculiar uracil bases was employed. To achieve the dual amplification strategy, we adopted hairpin probes HP1 and HP2. The unique hairpin probes can partially hybridize with S1 and S2, respectively. With the excision reaction of UDG, the uracil bases were excised from S2 in double-stranded S1-S2, resulting in a lower melting temperature of the S1-S2. Then, the S1-S2 was dissociated to single-stranded S1 and S2 with abasic sites. Subsequently, the liberated strands separately hybridized with hairpins to initiate the Exo III-catalyzed dual amplification. In the presence of K + , countless c-myc sequences which were produced by the amplification reaction formed G-quadruplex structures. Finally, with the addition of Mg 2+ , long and continuous G-wire structures were obtained, causing an obvious enhancement of RRS intensity. The proposed RRS DNA machine obtained the limit of detection as low as 1.0 × 10 −5 U/mL for the active UDG assay. Moreover, qualitative analysis of the active UDG was successfully achieved in HeLa cells lysate. The DNA machine is a potential tool to be used in UDG clinical diagnosis or functional study.
研究领域:
分子生物学
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分析化学
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生物医学工程
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临床诊断
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产品关联
DOI
高影响因子