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Potential-Controlled Adsorption, Separation, and Detection of Redox Species in Nanofluidic Devices.

ABSTRACT: Nanoscale channels and electrodes for electrochemical measurements exhibit extreme surface-to-volume ratios and a correspondingly high sensitivity to even weak degrees of surface interactions. Here, we exploit the potential-dependent reversible adsorption of outer-sphere redox species to modulate in space and time their concentration in a nanochannel under advective flow conditions. Induced concentration variations propagate downstream at a species-dependent velocity. This allows one to amperometrically distinguish between attomole amounts of species based on their time-of-flight. On-demand concentration pulse generation, separation, and detection are all integrated in a miniaturized platform.

SUBMITTER: Cui J

PROVIDER: S-EPMC6011178 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Potential-Controlled Adsorption, Separation, and Detection of Redox Species in Nanofluidic Devices.

Cui Jin J Mathwig Klaus K Mampallil Dileep D Lemay Serge G SG

Analytical chemistry 20180529 12

Nanoscale channels and electrodes for electrochemical measurements exhibit extreme surface-to-volume ratios and a correspondingly high sensitivity to even weak degrees of surface interactions. Here, we exploit the potential-dependent reversible adsorption of outer-sphere redox species to modulate in space and time their concentration in a nanochannel under advective flow conditions. Induced concentration variations propagate downstream at a species-dependent velocity. This allows one to amperome ...[more]

PMID: 29808992

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