ANALYTICAL CHEMISTRY
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2014
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IF 5.825
Yunxia Yuan,Runqing Li,Zhihong Liu
Layered WS2 nanosheet is a kind of two-dimensional (2D) covalent-network solid material with remarkable structural and electronic properties that has attracted increasing interest in recent years. In this work, we propose a one-step sonication-assisted exfoliation method to prepare water-soluble WS2 nanosheet and demonstrate its application as a biosensing platform. The synthesis route is simple and straightforward. We reveal that single-strand DNA (ssDNA) chains can readily be adsorbed on the nanosheet, leading to complete and fast quenching of a fluorescent dye tagged to the DNA chain. The adsorbed ssDNA is detachable from the nanosheet upon the interaction with other biomolecules, resulting in the restoration of the fluorescence. The 2D WS2 nanosheet thus acts as an efficient platform for assembling of bioprobes. Because of the extraordinarily high quenching efficiency, which is the synergic result of both excited-state energy transfer and static quenching, the WS2 platform affords minimal background and high sensitivity. Our attempt will extend the application of this material to biosensing and probing areas.
研究领域:
材料科学
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纳米技术
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生物传感器
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2023
·Vol. 47
·期 28
·13228-13234
·
IF 3.3
Yuanyi Wu,Shihan Liu,Yumei Xiao,Qian Li,Qin Xiang,Xianqin Song,Shanglin Wu,Kaiyong Wang,Yi Yang
Accurate detection of DNA is critical for biomedicine and food safety. Layered double hydroxides (LDHs) are a class of two-dimensional layered materials that have received extensive attention in the fields of sensors, catalysis, and materials science. The application of LDHs in DNA sensing in turn represents a fascinating topic. In this study, we found that both 6-carboxyfluorescein (FAM)-modified single-stranded DNA (ssDNA) probes and probe/target double-stranded DNA (dsDNA) duplexes could be adsorbed by LDHs, which resulted in high fluorescence quenching (>95%) for the first time. Based on the extraordinarily high quenching efficiency of LDHs, we developed a fluorescent sensing platform for simple and highly efficient detection of DNA, using Ni/Al-LDHs as fluorescence quenchers. For the selective degradation of dsDNA, exonuclease III was integrated into the sensor. In the sensing platform, the fluorescence of the probes was rapidly quenched by Ni/Al-LDHs. In the presence of the target DNA, dsDNA was formed, which was subsequently selectively degraded by exonuclease III into short fragments, resulting in the maintenance of the fluorescence of FAM labels. The linear range was 10–400 nM. The detection limit was 1.38 nM. This sensor accomplished the detection of target DNA within 50 min. It provides a convenient, rapid and versatile sensing platform for DNA biomarkers.
研究领域:
生物医学工程
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材料科学
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分析化学
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生物传感器
✓ 已验证
DOI
高影响因子
JOURNAL OF FLUORESCENCE
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2015
·Vol. 25
·期 5
·1267-1277
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IF 1.927
Huang Weidong,Wang Yue,Wang Zhimin
Single-molecule detection (SMD) and single-molecule fluorescence resonance energy transfer (smFRET) were conducted using Cy3- and Cy5-labeled single-strand DNAs (ssDNAs) either immobilized on substrates or encapsulated in microdroplets. High-quality fluorescent images were obtained using a total internal reflection fluorescence microscope (TIRFM). In the substrate system, deposition of a low concentration of fluorescence molecules on substrates through electrostatic adsorption showed that most of the fluorescence spots were single molecules, and the mean value of signal to noise ratio (S/N) reached 6.9 ± 0.34. smFRET analysis was conducted through immobilization of donor- and acceptor-labeled oligonucleotides on substrates. In the droplet system, fluorophor-labeled oligonucleotides were injected into T-type microfluidics. Single and double fluorophor-labeled DNA molecules encapsulated in droplets were detected, the FRET efficiency and inter-dye distance of a single donor-acceptor pair were measured accurately. smFRET was conducted detailedly in the tortuous channel for the first time.
研究领域:
生物化学
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分子生物学
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生物物理学
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产品关联
DOI
PubMed
高影响因子
Scientific Reports
·
2018
·Vol. 8
·期 1
·1-8
·
IF 4.122
Zhang Hong,Li Xintong,He Fan,Zhao Mingqin,Ling Liansheng
A novel turn-off colorimetric sensor for sequence-specific recognition of single-stranded DNA (ssDNA) was established by combining Y-shaped DNA duplex and G-quadruplex-hemin DNAzyme. A G-rich single-stranded DNA (Oligo-1) displays peroxidase mimicking catalytic activity due to the specific binding with hemin in the presence of K + , which was able to catalyze the oxidation of colorless 2,2′-azinobis(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS 2− ) by H 2 O 2 to generate green ABTS− radical for colorimetric assay. Oligonucleotide 2 (Oligo-2) was partly complementary with Oligo-1 and the target DNA. Upon addition of target DNA, Oligo-1, Oligo-2 and target DNA can hybridize with each other to form Y-shaped DNA duplex. The DNAzyme sequence of Oligo-1 was partly caged into Y-shaped DNA duplex, resulting in the inactivation of the DNAzyme and a sharp decrease of the absorbance of the oxidation product of ABTS 2− . Under the optimum condition, the absorbance decreased linearly with the concentration of target DNA over the range of 1.0–250 nM and the detection limit was 0.95 nM (3σ/slope) Moreover, satisfied result was obtained for the discrimination of single-base or two-base mismatched DNA.
研究领域:
生物化学
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分子生物学
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纳米技术
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分析化学
✓ 已验证
DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2023
·
IF 7.4
Duo Chen,Na Chen,Fangning Liu,Yiming Wang,Huageng Liang,Yanbing Yang,Quan Yuan
Portable point-of-care testing (POCT) is currently drawing enormous attention owing to its great potential for disease diagnosis and personal health management. Electrochemical biosensors, with the intrinsic advantages of cost-effectiveness, fast response, ease of miniaturization, and integration, are considered as one of the most promising candidates for POCT application. However, the clinical application of electrochemical biosensors-based POCT is hindered by the decreased detection sensitivity due to the low abundance of disease-relevant biomolecules in extremely complex biological samples. Herein, we construct a flexible electrochemical biosensor based on single-stranded DNA functionalized single-walled carbon nanotubes (ssDNA-SWNTs) for high sensitivity and stability detection of miRNA-21 in human urine to achieve bladder cancer (BCa) diagnosis and classification. The ssDNA-SWNT electrodes with a 2D interconnected network structure exhibit a high electrical conductivity, thus enabling the ultrasensitive detection of miRNA-21 with a detection limit of 3.0 fM. Additionally, the intrinsic flexibility of ssDNA-SWNT electrodes endows the biosensors with the capability to achieve high stability detection of miRNA-21 even under large bending deformations. In a cohort of 40 BCa patients at stages I–III and 44 negative control samples, the constructed ssDNA-SWNT biosensors could detect BCa with a 92.5% sensitivity, an 88.6% specificity, and classify the cancer stages with an overall accuracy of 81.0%. Additionally, the flexible ssDNA-SWNT biosensors could also be utilized for treatment efficiency assessment and cancer recurrence monitoring. Owing to their excellent sensitivity and stability, the designed flexible ssDNA-SWNT biosensors in this work propose a strategy to realize point-of-care detection of complex clinical samples to achieve personalized healthcare.
研究领域:
生物医学工程
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纳米技术
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癌症诊断
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电化学
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即时检测设备
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产品关联
DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
·
2022
·
IF 6.911
Wenrui Ma,Lulu Liu,Xu Zhang,Xingfei Liu,Yi Xu,Shunbo Li,Muling Zeng
Developing sensitive and miniaturized biosensors for the detection of microRNAs (miRNAs) is highly desirable due to their association with early cancer diagnosis and prognosis. Here, a new microfluidic-based biosensor, combined with multifunctional nanosurface and DSN-assisted target recycle amplification strategy, is designed for the detection of miRNA-21. The design of nanosurface includes gold nanoparticles on porous anodic aluminum oxide (AAO) for surface enhanced Raman scattering (SERS) substrate, Au MBA @Ag core-shell nanoparticles for SERS nanotags and single-stranded DNA (ssDNA) in between for miRNA capture and nanotags immobilization. When the target miRNA is present near the nanosurface, it will be captured by ssDNA via hybridization reaction. Then, triggered by the DSN-assisted target recycle process, the freshly formed DNA/miRNA heteroduplexes are cleaved by DSN enzyme into DNA fragments and single-strand miRNA. The SERS nanotags are also dissociated from the nanosurface, leading to decrease of SERS signal. The cleaved target miRNA can be captured and SERS nanotags are released again in the next cycle, resulting in amplification of detection signal. To improve the accuracy of this biosensor, the functionalized AAO membrane is subdivided into two groups - AAO/Au array linked with encoded core-shell SERS nanotags acting as a reactor and primary detector and AAO/ [email protected] array serving as a collector and secondary detector for the dissociative SERS nanotags from the reactor. The decrease of SERS signal in primary detector and increase of signal in secondary detector ensures the accuracy and it is called dual-SERS detection strategy. The detection of miRNA-21 can be achieved with only 30 μL sample and 10 μL enzyme and a wide linear range of 10 fM∼10 nM is obtained. In addition, the microfluidic dual-SERS detection strategy can greatly reduce the possibility of false positive or false negative in single detection mode and it can be applied to the simultaneous detection of multiple miRNAs via integrating different probes.
研究领域:
生物传感器
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微流控技术
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表面增强拉曼散射（SERS）
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纳米技术
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癌症诊断
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分子生物学
✓ 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）