JOURNAL OF MOLECULAR STRUCTURE
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2022
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IF 3.841
Xianqiang Song,Xin Chen,Zhaoxiong Liang,Dan Xu,Yong Liang
In this work, we present core/shell Au@MnO 2 nanoparticles-based visual sensing strategy for mercury ion (Hg 2+ ) detection. The MnO 2 shell of Au@MnO 2 nanoparticles catalyzes the oxidation reaction between tetramethylbenzidine (TMB) and oxygen in the air, generating blue derivative (oxTMB) with an absorption peak at 650 nm. Glutathione (GSH) inhibits the formation of oxTMB, reversing the reaction and turning it back into colorless TMB molecules. While in the existence of Hg 2+ , GSH binds to Hg 2+ due to the strong affinity between the Hg 2+ and the -SH, and in this situation, Au@MnO 2 catalyzes the oxidation of TMB to make the solution become blue. Using the colorimetric sensor, the detection limit of Hg 2+ reached as low as 0.473 nM by UV–vis spectroscopy and 1 nM under the naked eye observation, which is lower than toxicity level of Hg 2+ (10 nM) formulated by the U.S. Environmental Protection Agency.
研究领域:
分析化学
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环境科学
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DOI
高影响因子
MICROCHEMICAL JOURNAL
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2024
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IF 4.9
Yahang Li,Hanrui Zhou,Qing Song,Mingzhu Zou,Ying Wei,Qingguo Zhang
The emergence of flexible, painless sensors for biomolecule measurement represents a growing trend in biomedical research. In this context, a highly sensitive flexible sweat sensor, incorporating MnO 2 -TMB@PAM aggregates employing dual-detection routes via visualization and UV–vis spectrometry, has been developed. The sensor utilizes bovine serum albumin (BSA) templated MnO 2 nanoparticles (NPs) as a catalyst for glucose detection. Unlike natural enzymes, this nanozyme is not only cost-effective and stable but also exhibits tandem enzyme-like activities, which facilitates quick and straightforward glucose detection. MnO 2 NPs are synthesized in situ on the surface of polyacrylamide (PAM), ensuring high stability and increasing the contact area of reactors, thereby enhancing the catalytic efficiency of MnO 2 NPs . Additionally, 3,3′,5,5′-tetramethylbenzidine (TMB) is modified on the hydrogel to create an integrated sensing patch (referred to as MnO 2 -TMB@PAM). This patch enables fast and convenient sensing routes, positioning it as a potential candidate for point-of-care testing (POCT) devices. Due to the excellent flexibility and transmittance of PAM , the sensing patch allows for rapid colorimetric analysis of biomolecules such as glucose and dopamine via UV–vis spectrophotometry, as well as visual detection with the naked eyes. Consequently, a high-sensitive, selective, and visually active flexible sensor has been established based on colorimetric and visual methods, facilitating efficient sensing of biomarkers from in vitro biological fluids.
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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DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
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2022
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IF 12.545
Yingzhi Zhang,Jiayuan Fan,Jing Zhao,Zhangrun Xu
Exosomes, carrying specific molecular information of their parent cells, have been regarded as a kind of promising noninvasive biomarker for liquid biopsy. Plentiful fluorescence methods have been proposed for exosome assay. However, most of them are dependent on nucleic acid signal amplification strategies, which require complicated sequence design and experimental operation. Herein, a metal-enhanced fluorescence (MEF) biochip based on shell-isolated [email protected] 2 nanoparticle array was designed for simple and sensitive assay of exosomes. The designed method consists of only two parts: signal conversion and MEF amplification. The conversion of exosome signals to DNA signals was realized by means of chain displacement reaction. The subtle conversion effectively averts the effect of steric hindrance on MEF while amplifying the signal easily for the first time. The MEF biochip based on shell-isolated [email protected] 2 nanoparticle array achieves a second signal amplification in a simple way. Profiting from the two signal amplifications, this strategy displays high sensitivity toward exosomes with a detection limit of 4.5 × 10 3 particles μL −1 . Compared with the result without MEF, the sensitivity is enhanced about thirty times. As far as we know, this is the first attempt for exosome assay by using MEF strategy. In addition to the favorable fluorescence enhancement, both shell-isolated [email protected] 2 nanoparticles and [email protected] 2 nanoparticle array show excellent stability in buffer solutions, which is conducive to practical application. Moreover, the proposed method is able to distinguish breast cancer patients from healthy people, showing its potential for exosome-based liquid biopsy.
研究领域:
生物医学工程
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纳米技术
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癌症研究
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分子诊断
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DOI
PubMed
高影响因子
TALANTA
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2023
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IF 6.1
Hongding Zhang,Sifei Wu,Hui-Jin Xiao,Hai-Bo Wang,Linxia Fang,Jun-Tao Cao
Ultrasensitive analytical methods are still urgent for the discovery of trace level biomarkers and the early clinical diagnosis of disease. In this work, an ultrasensitive universal sensing platform was constructed by integrating fluorescent assay with chemical-chemical redox cycling signal amplification strategy. Using Ru@SiO 2 nanoparticles wrapped by MnO 2 nanosheets (Ru@SiO 2 @MnO 2 ) as fluorescent probe , the chemical-chemical redox cycling system was conducted upon ascorbic acid (AA) and tris(2-carboxyethyl)phosphine (TCEP) as reductants and MnO 2 nanosheets as oxidant. The MnO 2 nanosheets not only could quench the fluorescence of Ru@SiO 2 nanoparticles to reduce the background, but also could serve as oxidants to react with AA, generating dehydroascorbic acid (DHA). The DHA was reduced by TCEP in turn to form AA that participated in the next cycling of chemical-chemical redox reaction. Thus, the constantly released AA from the chemical-chemical redox cycling system could massively etch MnO 2 nanosheets on Ru@SiO 2 surface, making the fluorescence of Ru@SiO 2 nanoparticles greatly recovered. It was shown that the sensitivity of the fluorescent assay was improved almost 52 times by utilizing the chemical-chemical redox cycling signal amplification strategy. This strategy was further employed to detect DNA methylation with the aid of AA-encapsulated liposomes that were modified with 5 mC antibodies to bind with the methylated DNA captured in 96-well plate. A detection of limit down to 16.2 fM was achieved for the detection of methylated DNA. It's believed that the incorporation of chemical-chemical redox cycling signal amplification strategy into fluorescent sensing paves a new way for ultrasensitive detection of biomarkers.
研究领域:
分析化学
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生物标志物检测
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纳米技术
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生物化学
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产品关联
DOI
PubMed
高影响因子
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