Impedimetric immunosensor for the detection of histamine based on reduced graphene oxide

Abstract

In this work, we present a reduced graphene oxide‐based impedimetric histamine biosensor. Histamine as a bioamine mediates immune‐modulatory effects in acute inflammatory and allergic reactions. In a proof‐of‐principle approach, the low‐cost sensor platform determines low concentrations of histamine in buffer solution with an impedimetric readout technique. As a sensor platform we used ultra‐thin graphene oxide lines fabricated by a simple soft‐lithographic approach. The lines of about 20 μm width were characterised by atomic force microscopy and scanning electron microscopy. Reduction of graphene oxide to a conductive transducer material was performed by a rapid thermal protocol in inert atmosphere. The reduction process was monitored by impedance spectroscopy and X‐ray photoelectron spectroscopy. For our biosensor experiments we adopted a commonly‐used protocol for surface plasmon resonance (SPR) detection of histamine. With our reduced graphene oxide platform we detected antigen‐antibody binding events of histamine with concentrations of 0.1–1 μM via impedance changes in a low frequency range. The results from the rGO sensors were comparable to the SPR detection.