An integrated microfluidic system for affinity extraction and concentration of biomolecules coupled to MALDI-MS

We present an innovative microfluidic device that accomplishes integrated, all-aqueous realization of specific extraction, concentration, and coupling to mass spectrometric detection of biomolecular analytes. The device uses an aptamer (i.e., oligonucleotide that binds specifically to an analyte via affinity coupling) immobilized on microbeads to achieve highly selective analyte capture and concentration. Here, we demonstrate specific extraction and concentration of adenosine monophosphate (model analyte) by approximately 100x, while providing a reusable platform via sufficiently low temperature release and regeneration of the aptamer surface at 38 degC.