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Ring Ultramicroelectrodes for Current-Blockade Particle-Impact Electrochemistry.

ABSTRACT: In current-blockade impact electrochemistry, insulating particles are detected amperometrically as they impinge upon a micro- or nanoelectrode via a decrease in the faradaic current caused by a redox mediator. A limit of the method is that analytes of a given size yield a broad distribution of response amplitudes due to the inhomogeneities of the mediator flux at the electrode surface. Here, we overcome this limitation by introducing microfabricated ring-shaped electrodes with a width that is significantly smaller than the size of the target particles. We show that the relative step size is somewhat larger and exhibits a narrower distribution than at a conventional ultramicroelectrode of equal diameter.

SUBMITTER: Moazzenzade T

PROVIDER: S-EPMC9310007 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature

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Ring Ultramicroelectrodes for Current-Blockade Particle-Impact Electrochemistry.

Moazzenzade Taghi T Walstra Tieme T Yang Xiaojun X Huskens Jurriaan J Lemay Serge G SG

Analytical chemistry 20220706 28

In current-blockade impact electrochemistry, insulating particles are detected amperometrically as they impinge upon a micro- or nanoelectrode via a decrease in the faradaic current caused by a redox mediator. A limit of the method is that analytes of a given size yield a broad distribution of response amplitudes due to the inhomogeneities of the mediator flux at the electrode surface. Here, we overcome this limitation by introducing microfabricated ring-shaped electrodes with a width that is si ...[more]

PMID: 35792954

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