ANALYTICAL SCIENCES
·
2018
·Vol. 34
·期 2
·149-153
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IF 1.355
Xiao Fang ZHANG,Hong Mei XU,Lei HAN,Nian Bing LI,Hong Qun LUO
The detection of disease-related DNA is of great significance for early and accurate diagnosis and therapy. In this work, we successfully achieved the sensitive detection of target DNA based on a thioflavin T (ThT)-induced G-quadruplex fluorescent biosensor. ThT, a water-soluble fluorescent dye, can induce G-rich sequences to form G-quadruplexes and obtain an obviously enhanced fluorescence. In this work, it was employed to construct a biosensor for the detection of HIV. When the target HIV existed, the hairpin DNA probes would be opened in succession and release the completely exposed G-rich sequence to combine with ThT. The simple and rapid biosensor performed satisfactory selectivity; it also exhibited sensitivity with a detection limit of 2.4 nM. With good performance in human serum, we believe that this optical biosensor has the potential to be applied to the practical detection of target DNA.
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
PubMed
高影响因子
ELECTROANALYSIS
·
2017
·Vol. 29
·期 5
·1310-1315
·
IF 2.851
Panpan Zhang,Gulijamal Arken,Guixin Li,Ming Guan,Shuge Tian
A novel photo-induced electrochemical biosensing method has been developed based on fluorescence quenching effect and electrochemical method. In this sensing strategy, the molecular beacon probes labeled with methylene blue were immobilized on the gold nanoparticles modified gold electrode surface firstly; then dopamine was assembled on the electrode surface through electrostatic interaction with gold nanoparticles. Under the continuous illumination, the fluorescence of the methylene blue was quenched by the gold nanoparticles before hybridization; after hybridization with the complementary DNA, methylene blue was far away from the gold nanoparticles and the fluorescence recovered, and then singlet oxygen was generated in the photosensitive reaction of methylene blue in the presence of dissolved oxygen. Singlet oxygen reacted with dopamine, which resulted in the reduction of concentration of the dopamine on the electrode surface. The current of the dopamine on the electrode was used for the sensing of the conformational change of molecular beacon and hence for the detection of target DNA.
研究领域:
生物化学
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分析化学
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生物传感器
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产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
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2018
·Vol. 42
·期 6
·4714-4718
·
IF 3.201
Yu Ling,Xiao Fang Zhang,Xiao Hui Chen,Li Liu,Xiao Hu Wang,De Shou Wang,Nian Bing Li,Hong Qun Luo
Sensitive detection of disease-related DNA is of great significance for early and accurate diagnosis and therapy. To achieve this aim, we constructed a dual-cycling amplification biosensor for target oligonucleotide detection. Based on the toehold-mediated strand displacement reaction (TSDR), target DNA competitively hybridized with the assistant DNA which previously formed a duplex complex with the trigger DNA, and the trigger DNA was released. Exonuclease III (Exo III) would specially hydrolyze the assistant DNA in the new duplex DNA to free the target DNA for a new cycle. Similarly, based on the TSDR and Exo III assisted amplification, the released trigger DNA would repeatedly open the G-quadruplex hairpins and promote the generation of numerous G-quadruplex sequences. Then, the fluorescence intensity of Thioflavin T (ThT) would present apparent enhancement due to the formation of the G-quadruplex/ThT complex. The commercially available ThT is economical and of low toxicity. More importantly, owing to its satisfactory water solubility, ThT effectively avoids the introduction of organic solvents. There was no need for expensive modification through the whole process. The proposed method displayed high distinction efficiency towards target DNA against mismatched DNA. Additionally, the linear range of this strategy was 0.2–10 nM, and the detection limit was 0.04 nM. Besides, this sensor can be applied in human serum with satisfactory results.
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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产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2016
·
IF 4.758
Shulian Bai,Ting Wang,Zhang Zhang,Shangchun Sheng,Wen Yu,Guoming Xie
Adopting the concept and operation of hybridization-based associative toehold activation (HATA) concatemer induced catalyzed hairpin assembly (CHA), a novel colorimetric biosensor was developed for detecting target DNA and human alpha-thrombin. The assemble of separate DNA hairpin components can be triggered by specific target binding that are otherwise unable to spontaneously happen. In the presence of four ingeniously designed hairpin structures, the target molecule can trigger two cascade recycling reactions: HATA concatemer reaction and CHA reaction. In the HATA concatemer reaction, the toehold and branch migration domain overhang at the 5′ end and 3′ end of hairpin probe H1, respectively. Upon the addition of target molecule, plenty of toeholds and branch migration domains can be brought into close proximity via DNA self-assemble. Then, the toeholds and branch migration domains of HATA products serve as the trigger of CHA. In this concatemer recycling, numerous guanine rich DNA duplexes can be produced through the highly effective use of target molecule. The proposed sensing system exhibits a remarkable analytical performance and an ultrahigh discrimination capability for proximal mismatch. Under optimal conditions, the calibration curves have a good linearity from 1 pM to 75 nM and 1 pM to 2.5 nM for target DNA and human alpha-thrombin, respectively. The corresponding detection limits are 0.14 pMand 0.68 pM Therefore, this new biosensor has a great potential for further applications in biomedical research and demonstrates excellent versatility for different analytes.
研究领域:
生物技术
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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
NANO
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2020
·
IF 1.566
Zhikun Zhang,Xiaojie Ye,Qingqing Liu,Cuixia Hu,Jimmy Yun,Runjing Liu,Yumin Liu
Nucleic acid detection is becoming increasingly important in the diagnostics of genetic diseases for biological analysis. We herein propose gold nanoparticles as probe for colorimetric detection of nucleic acids with branched DNA nanostructures, which enables a novel and simple colorimetric biosensor. In our system, the target DNA specifically triggered two short-chain ssDNA probes to generate branched DNA nanostructures (Y-shape DNA), which prevent AuNPs from aggregation in aqueous NaCl solution. On the contrary, when the target DNA did not exist, gold nanoparticles were unstable and aggregated easily because there is no anti-aggregation function from Y-shape DNA. Sensor response was found to be proportional to the target DNA concentration from 5 to 100 nM, with detection limits determined as 5 nM. The developed platform is for colorimetric nucleic acid detection without enzymes, label and modification holds great promise for practical applications.
研究领域:
生物技术
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纳米技术
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分子生物学
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分析化学
✓ 已验证
产品关联
DOI
高影响因子
Analytical Methods
·
2021
·Vol. 13
·期 5
·712-718
·
IF 2.896
Jing Liu,Tianze Wang,Bo Xiao,Muhan Deng,Peng Yu,Taiping Qing
The breast cancer 1 (BRCA1) gene is a tumor suppressor gene, whose mutation is closely related to breast cancer. Therefore, the sensitive detection of the BRCA1 gene is extremely important for human health, particularly for women. In this study, a label-free fluorescent method based on hairpin DNA-templated copper nanoclusters (CuNCs) was for the first time developed for the detection of the BRCA1 gene. In the absence of target DNA, the detection system showed a strong red emission and produced a high emission peak. However, in the presence of the BRCA1 gene, the DNA probe hybridized with the BRCA1 gene and conformation of the DNA probe changed. As a result, the amount of produced CuNCs decreased and a low emission peak was obtained. The fluorescence intensity of the detection system was linearly correlated with the concentration of the BRCA1 gene ranging from 2 nM to 600 nM. The detectable limit was 2 nM for the BRCA1 gene assay, which was comparable with those reported by other non-amplifying sensors. Moreover, the developed method showed satisfactory recoveries for the BRCA1 gene assay in the bovine serum. The DNA-templated CuNC-based fluorescent assay thus offered a promising platform for the diagnosis of a breast cancer biomarker.
研究领域:
分子生物学
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癌症研究
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纳米技术
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生物医学工程
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分析化学
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产品关联
DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
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2018
·
IF 8.173
Xing-Pei Liu,Jing-Shuai Chen,Chang-jie Mao,He-Lin Niu,Ji-Ming Song,Bao-Kang Jin
A novel enhanced photoelectrochemical DNA sensor, based on a TiO 2 /Au hybrid electrode structure , was developed to detect target DNA. The sensor was developed by successively modifying fluorine-tin oxide (FTO) electrodes with TiO 2 nanoparticles , gold (Au) nanoparticles, hairpin DNA (DNA1), and CdSe-COOH quantum dots (QDs), which acted as signal amplification factors . In the absence of target DNA, the incubated DNA1 hairpin and the CdSe-COOH QDs were in close contact with the TiO 2 /Au electrode surface , leading to an enhanced photocurrent intensity due to the sensitization effect. After incubation of the modified electrode with the target DNA, the hairpin DNA changed into a double helix structure, and the CdSe QDs moved away from the TiO 2 /Au electrode surface, leading to a decreased sensitization effect and photoelectrochemical signal intensity. This novel DNA sensor exhibited stable, sensitive and reproducible detection of DNA from 0.1 μM to 10 fM, with a lower detection limit of 3 fM. It provided good specificity, reproducibility, stability and is a promising strategy for the detection of a variety of other DNA targets, for early clinical diagnosis of various diseases.
研究领域:
生物化学
·
分析化学
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纳米技术
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生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER
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2023
·
IF 4.6
Jianhan Ye,Xin Lu,Xiaohuan Zhao,Fen Wu,Yuanchen Dong,Qian Shi,Lijin Xu
The large-sized glass nanopipette (GN) allows for an access of large targets and show the benefits of excellent mechanical stability and reproducibility. The nanoscale DNA-decorated multilamellar cholesterol assemblies are introduced into the GN with several nanometers, and could in situ grow into a micrometer-scale aggregates under DNA signal stimulus, developing a simple and sensitive strategy for DNA detection in the micrometer-scale GN. The detection limit of target DNA reaches 2.69 fM in a GN with a diameter of up to ca. 4.76 μm.
研究领域:
纳米技术
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生物物理学
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分析化学
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分子生物学
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2012
·
IF 3.832
Xiaomeng Meng,Minrong Xu,Jianying Zhu,Huanshun Yin,Shiyun Ai
In this paper, a novel sensitive biosensor was fabricated for DNA detection based on gold nanoparticles (AuNPs) locked nucleic acid modified hairpin DNA probe (LNA-m-HpDNA) and enzymatic signal amplification. LNA-m-HpDNA dually labeled with 3′-thiol and 5′-biotin was efficiently assembled on the electrode via the interaction of thiol and gold. The stem-loop structure of LNA-m-HpDNA was unfolded after hybridization with target DNA, which forced biotin away from the electrode surface. Streptavidin-labeled horseradish peroxidase (Streptavidin-HRP) was subsequently immobilized on the electrode surface via the specific conjugation of biotin and streptavidin. Thereafter, the resulting HRP/target DNA–LNA-m-HpDNA (cDNA–LNA)/AuNPs modified Au electrode was successfully assembled for the construction of the DNA biosensor. Cyclic voltammetry and electrochemical impedance spectroscopy were carried out for the characterization of modified electrodes. Electrochemical reduction signal of benzoquinone was investigated in this work to indirectly analyze DNA hybridization via chronoamperometry. Under optimum conditions, the biosensor showed a good linear relationship between the current value and logarithm of the target DNA concentration ranging from 10 to 1000 pM with a low detection limit of 6.0 pM (S/N = 3). Furthermore, the DNA biosensor exhibited excellent discrimination ability to detect single-base mismatched DNA, three-base mismatched DNA and non-complementary DNA sequence. This strategy could provide a new platform for disease diagnose with high sensitivity.
研究领域:
生物化学
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纳米技术
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分子生物学
·
分析化学
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产品关联
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2022
·
IF 8.008
Jinzheng Zhang,Shuailong Zhou,Shiyi Tan,Kangyan Yi,Mengya Jin,Qian Shi,Fen Wu,Nannan Liu
Pore structure-based analytical techniques have great potential applications for the detection of biological molecules. However, the sophistication of traditional pore sensors is restricted in their applicability of analytical chemistry due to a lack of effective carrier probes. Here, we used porous coordination network-224 (PCN-224) composite probes in conjunction with a glass nanopipette (GN) as a sensing platform. The sensor exhibits a good fluorescence signal and a change in GN’s ionic current at the same time. Due to the volume exclusion mechanism coming from PCN-224, the detection limit of target DNA reaches 10 fM in a GN with a diameter of up to ca. 260 nm, outperforming a simple probe. The structure of the composite probe is optimized by the probe’s pairing efficiency. Furthermore, the sensor can also discriminate between 1-, 3-, and 5-mismatch DNA sequences and capture the target DNA from a complex mixture. Based on the GN platform, a series of techniques for detecting biomolecules are expected to emerge because of its simplicity, robustness, and universality by incorporating advanced nanoprobes.
研究领域:
分析化学
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生物传感器
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纳米技术
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2021
·Vol. 11
·期 33
·20046-20056
·
IF 3.361
Yuqi Huang,Shuhui Zhao,Wenxiu Zhang,Qiuyue Duan,Qi Yan,Hu Fu,Liang Zhong,Gang Yi
Nucleic acids are genetic materials in the human body that play important roles in storing, copying, and transmitting genetic information. Abnormal nucleic acid sequences, base mutations, and genetic changes often lead to cancer and other diseases. Meanwhile, methylated DNA is one of the main epigenetic modifications, which is considered to be an excellent biomarker in the early detection, prognosis, and treatment of cancers. Therefore, a multifunctional electrochemical biosensor was constructed with sturdy tetrahedral tripods, which assisted multiple tandem hairpins through base complementary pairing and effective ultra-sensitive detection of targets (DNA, microRNA, and methylated DNA). In the experiments, experimental conditions were optimized, and different DNA concentrations in serum were detected to verify the sensitivity of the biosensor and the feasibility of this protocol. In addition, microRNA and DNA methylation were detected through different designs of tetrahedral tripods (TTs) that capture probes to prove the superiority of this scheme. A sturdy pyramid structure of TTs extremely enhanced the capture efficiency of targets. The targets triggered the one-step isothermal multi-tandem amplification reaction by incubating multiple hairpin assemblies. To our knowledge, a combination of two parts, which greatly reduced background interference and decreased non-specific substance interference, has appeared for the first time in this paper. Moreover, the load area of electrochemical substances was significantly increased than that in previous studies. This greatly increased the detection range and detection limit of targets. The electrochemical signal responses were generated in freely diffusing hexaammineruthenium(III) chloride (RuHex). RuHex could adhere to the DNA phosphate backbone by a powerful electrostatic attraction, causing increased current responses.
研究领域:
生物传感器
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电化学
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纳米技术
·
分子生物学
·
癌症诊断
·
表观遗传学
✓ 已验证
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）