A disposable dry film photoresist-based microcapillary immunosensor chip for rapid detection of Epstein–Barr virus infection

Although there has been considerable progress in the development of engineering principles for miniaturized diagnostic devices, a substantial challenge remains to construct an integrated platform combining the advantages of low-cost production, easy handling and sensitive detection technique. We here report a new approach to disposable, polymeric bioanalytical microdevice: an immunosensor fabricated in Vacrel® 8100, a photoresist film that enables wafer-level production via simple lamination and photolithography in a non-cleanroom setting. The incorporated procedures of facile reagent delivery, fluid handling and amperometric detection using microfluidics allowed replicating the workflow of benchtop ELISA technique. The presence and accessibility of surface carboxyl groups enabled fast and versatile immobilization of biomolecules via amide crosslinking. We investigated the covalent bonding yield utilizing glucose oxidase and IR spectroscopy. To evaluate the platform, we show specific detection of an IgG-class antibody to Epstein–Barr virus (EBV) infection from a 5 μl human serum specimen with only a 2 min read-out time, which demonstrated 97.5% agreement with results obtained from a reference microplate format. Our approach offers the opportunity for rapid and low-cost microfluidic assays that enables easy-to-use point-of-care biomarker detection in clinically relevant samples.