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Updated: May 5, 2026

Engineering Molecular Recognition with Bio-mimetic Polymers on Single Walled Carbon Nanotubes
Published on: January 10, 2017
Single Molecule Discrimination of Heteropolytungstates and Their Isomers in Solution with a Nanometer-Scale Pore
Jessica Ettedgui1,2, John J Kasianowicz1, Arvind Balijepalli1
1Engineering Physics Division, Physical Measurement Laboratory, National Institute of Standards and Technology , Gaithersburg, Maryland 20899, United States.
Abstract:
We report a new method to identify metallic nanoclusters (polyoxometalate structures) in solution at the single molecule limit using a nanometer-scale pore. The technique allows the measurement of polyoxometalates with over 2 orders of magnitude lower analyte concentration than conventional analytical chemistry tools. Furthermore, pH-dependent structural changes in phosphotungstic acid are measured with protein nanopores and validated with NMR. We further demonstrate that the method can also discriminate [PW9O34](9-) structural isomers. The results suggest this technique can serve as a complementary approach to traditional methods.
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