International Journal of Analytical Chemistry
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2019
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IF 1.682
Kai Sun,Qingzhu Liu,Rui Zhu,Qi Liu,Shunyao Li,Youbin Si,Qingguo Huang
Certain nano-scale metal oxides exhibiting the intrinsic enzyme-like reactivity had been used for environment monitoring. Herein, we evaluated the oxidase-mimicking activity of environmentally relevant nano-MnO2 and its sensitivity to the presence of metal ions, and particularly, the use of MnO2 nanozyme to potentially detect Cu2+, Zn2+, Mn2+, and Fe2+ in water. The results indicated the oxidase-like activity of nano-MnO2 at acidic pH-driven oxidation of 2,6-dimethoxyphenol (2,6-DMP) via a single-electron transfer process, leading to the formation of a yellow product. Notably, the presence of Cu2+ and Mn2+ heightened the oxidase-mimicking activity of nano-MnO2 at 25°C and pH 3.8, showing that Cu2+ and Mn2+ could modify the reactive sites of nano-MnO2 surface to ameliorate its catalytic activity, while the activity of MnO2 nanozyme in systems with Zn2+ and Fe2+ was impeded probably because of the strong affinity of Zn2+ and Fe2+ toward nano-MnO2 surface. Based on these effects, we designed a procedure to use MnO2 nanozyme to, respectively, detect Cu2+, Zn2+, Mn2+, and Fe2+ in the real water samples. MnO2 nanozyme-based detecting systems achieved high accuracy (relative errors: 2.2–26.1%) and recovery (93.0–124.0%) for detection of the four metal ions, respectively. Such cost-effective detecting systems may provide a potential application for quantitative determination of metal ions in real water environmental samples.
研究领域:
环境科学
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生物化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2021
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IF 8.742
Yu Chen,Zenghui Mai,Senqing Fan,Yuyang Wang,Boya Qiu,Yilin Wang,Jiaojiao Chen,Zeyi Xiao
A catalytic membrane micro-reactor (CMMR) with nano MnO 2 /ZIF-8 immobilized in membrane pores has been fabricated by flowing synthesis and formaldehyde degradation was used to test its catalytic performance. The CMMR with deep-permeation nano structure (DPNS) has good stability, uniform nano MnO 2 /ZIF-8 dispersion and higher loading capacity. The MnO 2 coated on the surface of nano ZIF-8 with the size in the range of 100–150 nm was obtained. The contact between formaldehyde and MnO 2 is enhanced by the effect of even disperse of membrane pores. The enhanced mass transfer can be achieved in the micro-scale pores of the membrane by the confined space effect. A higher amount of MnO 2 loading and higher formaldehyde absorption rate can be achieved by the effect of ZIF-8 in membrane pores. The formaldehyde degradation rate was increased from 82.6% to 94.0%, if the MnO 2 loading capacity was increased from 98 mg g −1 to 344 mg g −1 .
研究领域:
化学工程
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环境科学
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产品关联
DOI
高影响因子
ANALYTICA CHIMICA ACTA
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2025
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IF 6
Jiabin Yang,Min Wang
Background Abnormal expression of microRNA (miRNA) is closely associated with the occurrence and development of cancer and various other diseases. Therefore, obtaining quantitative information on miRNA expression, especially detecting miRNA expression levels in living cells, is of great significance for studying related physiological and pathological processes as well as diagnosing diseases. RNA-cleaving DNAzyme (RCD)-based DNA walkers have shown great potential in the detection of miRNA. However, their application is hindered by low intracellular delivery efficiency, limited catalytic efficiency, and the requirement for additional supply of cofactors. Results In this study, we developed a novel self-feedback dual-walker (SFDW) nanosystem, loaded onto urchin-like nano-MnO 2 (UNM), for intracellular trace-level miR-21 imaging. The SFDW nanosystem incorporates a hairpin-structured capture probe and two mutually activating DNA walkers. During the detection process, the capture probe recognizes and binds to miR-21 in the matrix, opens the hairpin structure, and subsequently activates the DNA walkers. The cleavage product of each DNA walker in the nanosystem serves as the activator for the other, thereby establishing a biocircuit (self-feedback circuit) with cyclic amplification effect between the two. This mechanism significantly enhances the signal amplification capability. The UNM carrier not only promotes cellular uptake for the SFDW nanosystem, but supplies endogenous Mn 2+ cofactors via intracellular glutathione-triggered degradation as well. The SFDW nanosystem achieved a low detection limit of 2.8 pM, and successfully enabled miRNA visualization in living cells. Significance The self-feedback circuit improved detection sensitivity and reduced the detection limit, while the introduction of UNM enhanced delivery efficiency and provided the necessary cofactors. This proposed strategy can address the limitations of RCD-based DNA walkers in intracellular miRNA detection and holds great potential for clinical diagnosis and early-stage disease screening.
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产品关联
DOI
PubMed
高影响因子
TEXTILE RESEARCH JOURNAL
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2023
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IF 2.3
Qi Wang,Mengfan Wang,Jiali Sun,Xiaolin Zhang,Weichun Chen,Xichen Yu,Wei Fan
With rapid development in the smart wearable field, new-style flexible energy storage devices are necessary to satisfy the demands of flexible smart clothing. Thereinto, fiber supercapacitors present promising application prospects. This work puts forward a facile and reliable strategy to fabricate coaxial fiber electrodes via binary wet spinning, and further assembles them into parallel or twisted nano-MnO2 fiber supercapacitors. In the obtained fiber electrode, a carboxymethylcellulose layer onto nano-MnO2 not only allows the requisite ion exchange between the electrochemical active materials and gel electrolyte, but also plays the role of separator to protect the two fiber electrodes effectively from contacting a short circuit, greatly ensuring the electrochemical stability of the nano-MnO2 fiber supercapacitors. The parallel nano-MnO2 fiber supercapacitor reaches a maximum CL of 19.7 μF/cm, EL of 0.0027 μWh/cm and PL of 1.49 μW/cm; the twisted MnO2 fiber supercapacitor achieves maximum CL, EL and PL of 49 μF/cm, 0.0053 μWh/cm and 1.0 μW/cm, respectively. Besides, the outstanding softness and tensile properties of the obtained nano-MnO2 fiber supercapacitors also guarantee stable electrochemical performance under bending, knotting or other large-distortion situations, which is beneficial to develop a new generation of metal oxide fiber supercapacitors for smart wearable clothing.
研究领域:
材料科学
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能源存储
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智能纺织品
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）