Electrochemical detection of enzyme kinetics using a nanofluidic thin layer cell device.

Abstract

ABSTRACT
We have developed a lithography-based nanofluidic device for sensitive electrochemical detection applications. The
device consists of a solution-filled channel bounded by parallel electrodes that are separated by ~50 nm. Redox cycling
at the two electrodes is used to amplify the electrochemical signals from molecules in the volume between the electrodes,
and can lead to dramatic improvements in sensitivity and/or selectivity. Interestingly, an important limit to sensitivity is
placed by statistical fluctuations in the number of molecules present in the device, a consequence of its extremely small
volume (a few femtolitres). In this Proceedings article, we focus on the consequences of these statistical fluctuations on
the signal-to-noise ratio of electrochemical sensors based on redox cycling.
KEYWORDS: Nanofluidics, electrochemistry, sensing, number fluctuations, mesoscopic.