High-sensitivity electrochemical enzyme-linked assay on a microfluidic interdigitated microelectrode.

ABSTRACT: A novel enzyme-linked DNA hybridization assay on an interdigitated array (IDA) microelectrode integrated into a microfluidic channel is demonstrated with sub-nM detection limit. To improve the detection limit as compared to conventional electrochemical biosensors, a recyclable redox product, 4-aminophenol (PAP) is used with an IDA microelectrode. The IDA has a modest and easily fabricated inter-digit spacing of 10 μm, yet we were able to demonstrate 97% recycling efficiency of PAP due to the integration in a microfluidic channel. With a 70 nL sample volume, the characterized detection limit for PAP of 1.0 × 10⁻¹⁰ M is achieved, with a linear dynamic range that extends from 1.0 × 10⁻⁹ to 1.0 × 10⁻⁵ M. This detection limit, which is the lowest reported detection limit for PAP, is due to the

SUBMITTER: Chen IJ 

PROVIDER: S-EPMC3120925 | biostudies-literature | 2011 Jul

REPOSITORIES: biostudies-literature