Performance of a Faradaic impedimetric immunosensor for blood group antigen A

The performance is described of a label-free Faradaic impedimetric immunosensor based on immobilized monoclonal IgM antibodies to blood group antigen A (anti–A) for blood typing. Anti–A was directly immobilized onto gold electrodes modified with an amine-reactive self assembled monolayer of dithiobis(succinimidylundecanoate). The alteration of the interfacial features of the electrodes due to different modification or recognition steps was probed by Faradaic impedance spectroscopy and cyclic voltammetry in the presence of a hexacyanoferrate(II)/(III) redox couple. Various optimization studies were undertaken with respect to the construction and potential use of the immunosensors as a diagnostic tool for blood typing.