ANALYST
·
2016
·Vol. 141
·期 20
·5829-5834
·
IF 4.033
Xiangmin Miao,Zongbing Li,Liansheng Ling
An ultrasensitive fluorescent platform for sequence-specific recognition of double-stranded DNA (dsDNA) based on the quenching of gold nanoparticles (AuNPs) to a fluorophore labeled DNA probe was developed. The target dsDNA could hybridize with the loop portion of the molecular beacon (MB) to form a triplex DNA structure and opened the “stem–loop” structure of the MB; such triplex DNA was used as an assistant probe (AP). Meanwhile, a fluorophore labeled DNA-AuNP probe that contained a specific enzyme cleavage site was introduced and its fluorescence signal was efficiently quenched due to the vicinity of the fluorophore to the AuNP surface. Such a DNA-AuNP probe could hybridize with the 5′ stem portion of the MB in the AP to form duplex DNA strands that contained a specific enzyme cleavage site for the nicking enzyme assisted cleavage reaction, and resulted in the release of the fluorophore from the AuNP surface and the recovery of the fluorescence signal. Because the AP remains intact during such a cleavage process, it could be reused to hybridize with the next DNA-AuNP probe and trigger the nicking nuclease assisted signal amplification. Under optimal conditions, a low detection limit of 3.8 pM was obtained for dsDNA detection, and the assay has high sequence specificity for dsDNA detection.
研究领域:
生物化学
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纳米生物学
·
分子诊断
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产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2015
·
IF 4.097
Pei Liu,Min Liu,Hunshun Yin,Yunlei Zhou,Shiyun Ai
Aberrant DNA methylation, which is caused by the abnormal level of DNA methyltransferase (MTase), has been considered associated with a growing number of human diseases. Although there are various methods paying close attention to DNA methyltransferase (MTase) detection, most of them are generally complex and expensive. Here, a simple electrochemical strategy for sensitive detection of DNA methyltransferase (MTase) and inhibitor screening based on DpnI digestion triggering the formation of G-quadruplex DNAzymes has been developed. In this paper, a probe richness of guanine (G) was first self-assembled on the surface of the electrode through Au–S bond and then hybridized with the complementary DNA. Without DNA methylation, G-quadruplex DNAzymes cannot be formed due to the double helix structure and a weak electrochemical response can be observed. On the contrary, an obvious enhancement of the electrochemical response can be achieved after the cleavage of the methylated double-strand DNA by DpnI since G-quadruplex DNAzymes can be obtained, which catalyze the oxidation of hydroquinone by H 2 O 2 with the assistance of the cofactor hemin. This method is under a detection limit of 0.96 U/mL and can monitor the change of DNA methylation level selectively. Moreover, RG108 was selected as a representative inhibitor for studying the inhibition activity of DNA MTase.
研究领域:
生物化学
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分子生物学
·
分析化学
✓ 已验证
DOI
高影响因子
BIOELECTROCHEMISTRY
·
2024
·
IF 4.8
Haotian Xie,Zhaojiang Yin,Guobin Wei,Binghui Li,Hanfeng Cui,Hao Fan,Jing Zhang
This study developed a dual-mode “on-off-on” sensor based on a bipyridine ruthenium metal–organic framework (Ru-MOF) and dual enzyme cleavage technology for the sensitive detection of the K-ras gene. The sensor combines electrogenerated chemiluminescence (ECL) and fluorescence (FL) detection modes, achieving high sensitivity and specificity in detecting the K-ras gene through catalytic hairpin assembly (CHA) and dual enzyme cleavage reactions. Experimental results showed that the detection limits for the K-ras gene were 0.044 fM (ECL) and 0.16 fM (FL), demonstrating excellent selectivity and stability during detection. Through testing actual samples, the sensor has shown potential for application in complex biological environments. This method offers an efficient and reliable new tool for cancer diagnosis and treatment.
研究领域:
生物传感
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分子诊断
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癌症研究
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产品关联
DOI
PubMed
高影响因子
Science Advances
·
2020
·Vol. 6
·期 43
·
IF 13.117
Miaomiao Zhang,Yong Guan,Zheng Dang,Pinggen Zhang,Zhen Zheng,Liang Chen,Wen Kuang,Chenchen Wang,Gaolin Liang
Directly observing intracellular nanostructure formation remains challenging. In this work, using a rationally designed small-molecule 4-nitrobenzyl carbamate–Cys(SEt)-Asp-Asp-Phe(iodine)–2-cyano-benzothiazole (NBC-Iod-CBT), we directly observed intracellular nanoparticle formation with nanocomputed tomography (nano-CT). In vitro, upon glutathione reduction and nitroreductase (NTR) cleavage, NBC-Iod-CBT undergoes a CBT-Cys click condensation reaction to self-assemble nanoparticles Iod-CBT-NPs with an average linear absorption coefficient (LAC) value of 0.182 ± 0.078 μm −1 to x-ray. Nano-CT imaging of the NBC-Iod-CBT–treated, NTR-overexpressing HeLa cells showed the existence of Iod-CBT-NPs in their cytoplasm with an average LAC value of 0.172 ± 0.032 μm −1 . We anticipate that our strategy could help people to deeply understand the formation mechanism of intracellular nanostructures in the near future.
研究领域:
纳米技术
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生物医学成像
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分子生物学
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细胞生物学
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2020
·Vol. 44
·期 42
·18250-18255
·
IF 3.288
Lunxi Duan,Hongliang Yao,Yong Xie,Ke Pan
Due to significant roles in cellular functions and cancer treatments, the development of efficient methods to monitor protein–ligand interactions is essential. Herein, we developed a highly selective fluorescence strategy for protein activity detection using a ligand-modified DNA and nucleic acid dye SYBR Green I (SGI). In order to verify our approach, streptavidin (SA) and biotin were selected as model molecules to be investigated. In the presence of targeted protein SA, the biotin-modified hpDNA can bind with SA and protect the hpDNA from enzymatic degradation. Then, the intact hpDNA can excite the fluorescence signal of free SGI. However, the unprotected hpDNA would undergo hydrolysis reactions to produce short fragments in the presence of Exo III and fail to excite the fluorescence of the SGI dye. So, the fluorescence change of SGI can be used to identify SA activity and SA–biotin interaction. This high-specific and label-free fluorescence method can detect protein in buffers as well as biological samples. Our proposed method provided good selectivity and high sensitivity with a detection limit of 0.001 μg mL−1 for SA detection. We believe that this strategy presents a promising platform for high-throughput protein–ligand interaction screening. Moreover, this method can also be applied to monitor other proteins by replacing ligands.
研究领域:
生物化学
·
分子生物学
·
癌症研究
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2025
·
IF 5.5
Yanci Zhang,Yujin Fan,Jiyuan Zhang,Yanxi Hu,Lili Duan,Zhanhui Wang,Yihong Wang,Jiansheng Cui,Liang Tian
The imbalanced expression of microRNA is related to many diseases and tumors, which can be used as a noninvasive biomarker to assist in the diagnosis, prognosis, and monitoring of cancer. A target conversion strategy-based electrochemical biosensor was developed by DNAzyme-cleavage dual cyclic signal amplification and the strand displacement reaction (SDR) to produce high electrochemical signals for microRNA-155 (miRNA-155) analysis. Thereinto, VSe2/multi-walled carbon nanotubes (MWCNTs) with high conductivity were applied as the electrode surface material to provide more active sites and accelerate electron transportation. Then, the excellent immobilization efficiency and large specific surface area of the ZnO@CuS nanoprobes were applied as a recognition molecule carrier. Furthermore, hexaammineruthenium(III) chloride (RuHex), with superior electrochemical redox activity, acted as the electroactive indicator by intercalating into double-helix DNA through electrostatic interaction, which produced high current responses in the presence of the target. Therefore, this miRNA-155 biosensing platform exhibited a relatively low limit of detection of 0.11 fM, ranging from 0.5 fM to 5 nM, and demonstrated excellent repeatability and stability. Hence, this platform appeared to possess favorable human serum detection capacity and be suitable for early cancer diagnostics.
研究领域:
生物医学工程
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分子诊断学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Xin Feng,Hankun Zhu,Yugui Wang,Yong Yu,Hongjie Dai,Liang Ma,Yuhao Zhang
The traditional gelatin extraction methods (acid-base) may hinder to their green applications due to mass energy consumption and pollution. Herein, we constructed a clean and sustainable gelatin extraction method, investigated the molecular mechanism of microwave treatment (0–360 min) and freeze-thaw on the gelatin extraction from the perspective of the crosslinking degree and hydrogen bonds. Microwave (0–60 min) can improve the hydrolysis degree (DH) and expose more enzyme cleavage sites of collagen by destroying the intramolecular and intermolecular covalent crosslinking. Freeze-thaw loosened the collagen structure mainly by destroying hydrogen bonds, further increased degree of freedom, DH and enzyme cleavage sites, improved the gelatin yield and gel strength. However, the long-term microwave treatment (60–360 min) severely damaged the covalent crosslinking, increased the DH and enzyme cleavage sites. Freeze-thaw further loosened the collagen structure, caused the rapid dissolution and degradation of subunit, improved the gelatin yield and reduced the gels strength.
研究领域:
食品科学
·
材料科学
·
可持续化学
·
生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2015
·
IF 6.723
Cuiyun Yang,Kai Shi,Baoting Dou,Yun Xiang,Yaqin Chai,Ruo Yuan
On the basis of the use of silver nanoclusters (AgNCs) in situ synthesized by cytosine (C)-rich loop DNA templates as signal amplification labels, the development of a label-free and highly sensitive method for electrochemical detection of microRNA (miRNA-199a) is described. The target miRNA-199a hybridizes with the partial dsDNA probes to initiate the target-assisted polymerization nicking reaction (TAPNR) amplification to produce massive intermediate sequences, which can be captured on the sensing electrode by the self-assembled DNA secondary probes. These surface-captured intermediate sequences further trigger the hybridization chain reaction (HCR) amplification to form dsDNA polymers with numerous C-rich loop DNA templates on the electrode surface. DNA-templated synthesis of AgNCs can be realized by subsequent incubation of the dsDNA polymer-modified electrode with AgNO3 and sodium borohydride. With this integrated TAPNR and HCR dual amplification strategy, the amount of in situ synthesized AgNCs is dramatically enhanced, leading to substantially amplified current response for highly sensitive detection of miRNA-199a down to 0.64 fM. In addition, the developed method also shows high selectivity toward the target miRNA-199a. Featured with high sensitivity and label-free capability, the proposed sensing scheme can thus offer new opportunities for achieving sensitive, selective, and simple detection of different types of microRNA targets.
研究领域:
生物化学
·
分子生物学
·
纳米技术
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2024
·
IF 8
Huinan Chen,Jingyao Song,Yuanyuan Li,Dongmei Deng,Yuchen Song,Xiaoli Zhu,Liqiang Luo
Tumor biomarkers are a kind of important biomolecules for aiding cancer diagnosis and assessing tumor efficacy, among which alpha-fetoprotein (AFP) is a crucial tumor biomarker for the early diagnosis of hepatocellular carcinoma. In this study, a novel cascade signal amplifying strategy was designed for the ultrasensitive detection of AFP by DNAzyme cleaving-mediated hybridization chain reaction (HCR). The primary antibody was immobilized on the Au nanoparticles modified glassy carbon electrode, which subsequently captured AFP and the secondary antibody. Then, streptavidin was combined with the biotin-modified secondary antibody and Cu 2+ -specific DNAzyme. When Cu 2+ was present, the substrate strand of the DNAzyme would cleave and produce an ssDNA end. Finally, HCR was triggered to form long double-stranded DNA on the electrode, which would greatly inhibit the charge transfer at the electrode/solution interface. Therefore, the DNAzyme cleaving-mediated HCR strategy can be applied as cascade signal amplification for the ultrasensitive electrochemical determination of tumor biomarker AFP. Under optimal conditions, the immunosensor exhibits a broad linear range of 0.001−100 ng·mL −1 (R 2 = 0.990) and a low detection limit of 15.8 fg·mL −1 . The proposed sensor displays high sensitivity and selectivity for AFP detection, which can be employed as a universal sensing platform in clinical diagnostics.
研究领域:
生物医学工程
·
分析化学
·
癌症诊断
✓ 已验证
产品关联
DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2021
·
IF 10.618
Qiong Hu,Luofeng Su,Yan Mao,Shiyu Gan,Yu Bao,Dongdong Qin,Wei Wang,Yuwei Zhang,Li Niu
Being closely associated with a variety of physiological and pathological processes, matrix metalloproteinases (MMPs) are useful as potential targets for drug therapy and informative markers for disease diagnosis. On the basis of the electrochemically induced grafting of ferrocenyl polymers and the proteolytic cleavage of recognition peptide, a novel electrochemical sensor is presented in this work for the highly specific interrogation of MMP activities at ultralow levels. The recognition peptide, to be immobilized via the N-terminus, is free of carboxyl group. The presence of the target MMP would cleave the end-tethered recognition peptide, generating a free carboxyl group at the C-terminus of the rest fragment. To be used as the reversible addition−fragmentation chain-transfer (RAFT) agent, the dithiobenzoate, 4-cyano-4-(phenylcarbonothioylthio)pentanoic acid (CPAD), can therefore be tethered via the carboxylate-Zr(IV)-carboxylate chemistry. Subsequently, the grafting of ferrocenyl polymers through electrochemically induced RAFT (eRAFT) polymerization of ferrocenylmethyl methacrylate (FcMMA) would recruit a large quantity of Fc redox reporters on electrode surface . With benefits from the excellent specificity of the enzyme-substrate recognition, the presented cleavage-based sensor is highly selective. Under optimal conditions, the detection limit in the presence of MMP-2 as the model target can be as low as 0.27 pg mL −1 , with a linear range from 1 pg mL −1 to 1 ng mL −1 . Furthermore, its applicability in the interrogation of MMP activity in complex serum samples and the screening of MMP inhibitors is satisfactory. The presented cleavage-based electrochemical MMP sensor is easy to fabricate and low-cost, thus showing great promise in drug discovery and disease diagnosis.
研究领域:
生物化学
·
分析化学
·
生物传感器
·
药学
·
诊断学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2022
·
IF 9.231
Pengfei Ma,Hua Ye,Hualin Guo,Xiaoyuan Ma,Lin Yue,Zhouping Wang
Herein, for the first time, a novel truncation strategy for aptamers’ sequences based on molecular docking was reported for the first time. T-2 toxin and AFB 1 aptamers were employed as models and fluorescence polarization was used to measure the affinity of aptamers. The T-2 toxin aptamer (T40) with 40 bases and the AFB 1 aptamer with 32 bases were successfully obtained with increased affinities compared with original aptamers. Meanwhile, circular dichroism, FAM-BHQ1 dual labeled T40, enzyme digestion, and molecular dynamics simulation were performed to investigate the binding mechanism between aptamer T40 and T-2 toxin. Finally, based on MnO 2 nanosheet and the fluorescence amplification effect of SYBR Green I, simplified and rapid fluorescence detection of T-2 toxin was achieved with a detection range of 0.03 nM to 30 nM, indicating the great potential of aptamer in practical detection applications.
研究领域:
分析化学
·
分子生物学
·
毒理学
·
纳米技术
✓ 已验证
DOI
PubMed
高影响因子
NANOTECHNOLOGY
·
2022
·Vol. 33
·期 16
·165102
·
IF 3.953
Weilun Sun,Jingjing Xu,Bo Liu,Yuan-Di Zhao,Ling Yu,Wei Chen
Phage is a promising therapeutic agent for treating antibiotic resistant bacteria. However, in the process of treatment, phage may be cleared by the immune system and cleaved by protease, which could affect the efficacy of phage. In order to solve the above problems, phage encapsulation is usually adopted. In this study, we employed metal phenolic network (MPN) for efficient phage encapsulation which could protect phage from the cleavage of protease, and keep cytotoxicity weak. In the model of skin wound infection, the encapsulated phage could be released in response to pH change to achieve good antibacterial effect. Furthermore, the MPN encapsulation could prolong the T4 phage residence time at the wound. Our findings suggest that MPN can be a promising material for phage encapsulation.
研究领域:
药学
·
生物技术
·
微生物学
·
材料科学
✓ 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）