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We report a label-free nanopore sensor for the detection of Zn 2+ ions. By taking advantage of the cleavage of a substrate peptide by zinc-dependent enzymes, nanomolar concentrations of Zn 2+ ions could be detected within minutes. Furthermore, structurally similar transition metals such as Ni 2+ , Co 2+ , Hg 2+ , Cu 2+ , and Cd 2+ did not interfere with their detection. The enzymatic reaction-based nanopore sensing strategy developed in this work may find potential applications in environmental monitoring and medical diagnosis.
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Rapid and sensitive detection of the activity of ADAM17 using a graphene oxide-based fluorescence sensor
A disintegrin and metalloproteinase 17 (ADAM17) has become a novel biomarker and potential therapeutic target for the early detection and treatment of human cancers. In this work, by covalently attaching fluorescently labeled ADAM17 substrate peptide (Pep-FAM) molecules to carboxylated graphene oxide (cGO) and monitoring the cleavage of the peptide substrate by ADAM17, we developed a cGO-Pep-FAM fluorescence sensor for the rapid, sensitive and accurate detection of ADAM17. The sensor was highly sensitive with a detection limit of 17.5 picomolar. Furthermore, the sensor was selective: structure similar proteases such as ADAM9 and MMP-9 would not interfere with ADAM17 detection. In addition, simulated serum samples were successfully analyzed. Our developed cGO-Pep-FAM sensing strategy should find useful applications in disease diagnosis and drug screening.
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- Award ID(s):
- 1708596
- PAR ID:
- 10094111
- Date Published:
- Journal Name:
- The Analyst
- Volume:
- 144
- Issue:
- 5
- ISSN:
- 0003-2654
- Page Range / eLocation ID:
- 1825 to 1830
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/c8an02344a
