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Solid-nanopores/nanopipettes have the exquisite ability to reveal the changes in molecular volume due to the advantages of adjustable size, good rigidity and low noise. Herein, a new platform for sensing application was established based on G-quadruplex-hemin DNAzyme (GQH) functionalized gold-coated nanopipettes. In this method, GQH was immobilized on gold-coated nanopipette, which could be used as a catalyst for the reaction of HO with 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) to promote the conversion of ABTS to ABTS ions inside gold-coated nanopipette, and the change of transmembrane ion current could be monitored in real time. At the optimal conditions, there was a correlation between the ion current and the concentration of HO in a certain range, which could be used for the hydrogen peroxide sensing. The GQH immobilized nanopipette provides a useful platform to investigate enzymatic catalysis in confined environment, which can be used in electrocatalysis, sensing and fundamental electrochemistry.
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http://dx.doi.org/10.1016/j.talanta.2023.124384 | DOI Listing |
Talanta
August 2025
College of Chemistry and Materials Science, Sichuan Normal University, Chengdu, 610066, China. Electronic address:
Herein, a simple yet powerful label-free electrochemical sensing platform developed for dual detection of Pb and malathion by ingeniously integrating Pb-dependent DNAzyme and malathion aptamer into a triplex DNA structure. The designed DNA complex not only served as dual recognition elements but also functioned as signal amplifiers through DNA walker activity triggered by target binding. When detecting Pb, the activated DNAzyme initiated cyclic cleavage of substrate DNA, thereby generating numerous G-quadruplex/hemin complexes that produced significantly enhanced electrochemical signal and achieved its signal-on detection.
View Article and Find Full Text PDFTalanta
August 2025
School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212003, PR China.
The abnormal expression of microRNA (miRNA) is closely related to the occurrence and progression of diverse cancers. Accurate diagnosis of early-stage cancers via low-cost Point-of-Care Testing (POCT) remains highly desirable but challenging. Herein, a dual-colorimetric amplification biosensor has been developed for the simultaneous detection of two tumor-associated miRNAs.
View Article and Find Full Text PDFBioelectrochemistry
December 2025
Shanghai Engineering Research Center of Food Rapid Detection, School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China. Electronic address:
Copper is an essential trace element that plays critical roles in numerous physiological processes, including mitochondrial respiration, antioxidant defense, and neurotransmitter biosynthesis. However, an imbalance in copper homeostasis can lead to severe health disorders. Copper deficiency is linked to diseases such as anemia and neutropenia, while copper overload is associated with neurodegenerative diseases like Wilson's disease and Alzheimer's disease.
View Article and Find Full Text PDFAnal Chem
July 2025
School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
The correct spatial folding of the aptamer significantly influences its binding performance with the target. By extending the terminal double-stranded domain of the hemin aptamer, we obtained apt71 with a more stable spatial conformation. The catalytic activity of the resulting apt71/hemin DNAzyme reached 200% of that of the original aptamer.
View Article and Find Full Text PDFBiosens Bioelectron
November 2025
College of Chemistry and Materials Science, Sichuan Normal University, Chengdu, 610066, China. Electronic address:
Developing sensitive multi-target-combined detection method is of great significance for the early and accurate diagnosis and prognosis of hepatocellular carcinoma (HCC). Herein, an electrochemical biosensor was proposed for detecting HCC biomarkers miRNA 122 and alpha-fetoprotein (AFP), employing a DNA triangular prism (DTP) nanostructure as an efficient supporting platform integrated with a DNAzyme-hybridization chain reaction (HCR)-CRISPR/Cas12a triple signal amplification strategy. The ssDNA portion at the top of the DTP hybridized with ssDNA (S6) rich in guanine, thereby capturing hemin and forming G-quadruplex/hemin complexes, generating a strong initial electrochemical signal.
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