An aptamer-based microfluidic device for thermally controlled affinity extraction

Microfluidics and Nanofluidics (Impact Factor: 2.67). 04/2008; 6(4):479-487. DOI: 10.1007/s10404-008-0322-4

ABSTRACT We present a microfluidic device for specific extraction and thermally activated release of analytes using nucleic acid aptamers.
The device primarily consists of a microchamber that is packed with aptamer-functionalized microbeads as a stationary phase,
and integrated with a micro heater and temperature sensor. We demonstrate the device operation by performing the extraction
of a metabolic analyte, adenosine monophosphate coupled with thiazole orange (TO-AMP), with high selectivity to an RNA aptamer.
Controlled release of TO-AMP from the aptamer surface is then conducted at low temperatures using on-chip thermal activation.
This allows isocratic analyte elution, which eliminates the use of potentially harsh reagents, and enables efficient regeneration
of the aptamer surfaces when device reusability is desired.

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