Biosensors: Graphene‐Oxide‐Based Immunosensing through Fluorescence Quenching by Peroxidase‐Catalyzed Polymerization (Small 13/2012)

Graphene oxide (GO), an intermediary of graphene nanosheets, possesses many unique properties. The present immunosensing platform utilizes innate fluorescence of GO, not demanding biomolecules labeled with fluorescent dyes used in other types of optical biosensors. Peroxidase-catalyzed polymerization of a dye (e.g., diaminobenzidine) directly quenches the innate fluorescence of GO, which does not require anadditional quenching probe. Based on the phenomenon, a highly sensitive immunosensor is developed for the detection of target analytes, such as interleukin-5, a key cytokine associated with asthma pathology and eosinophilia. The GO-based immunoassay system can extend its application to the detection of other target chemicals and high-throughput screening.