%0 Journal Article
%T Pushing the Limits of Electrical Detection of Ultralow Flows in Nanofluidic Channels
%A Klaus Mathwig
%A Serge G. Lemay
%J Micromachines
%D 2013
%I MDPI AG
%R 10.3390/mi4020138
%X This paper presents improvements in flow detection by electrical cross-correlation spectroscopy. This new technique detects molecular number fluctuations of electrochemically active analyte molecules as they are transported by liquid flow through a nanochannel. The fluctuations are used as a marker of liquid flow as their time of flight in between two consecutive transducers is determined, thereby allowing for the measurement of liquid flow rates in the picoliter-per-minute regime. Here we show an enhanced record-low sensitivity below 1 pL/min by capitalizing on improved electrical instrumentation, an optimized sensor geometry and a smaller channel cross section. We further discuss the impact of sensor geometry on the cross-correlation functions.
%K flow detection
%K electrochemical sensor
%K nanofluidics
%K cross-correlation
%K nanochannel
%K redox cycling
%U http://www.mdpi.com/2072-666X/4/2/138