Scheme 1. Schematic illustration of the as-prepared Hb-protected ultra-small Au nanoclusters and their multiple functions. Within the Hb@AuNCs, the Hb provides oxygen (O2) binding and releasing properties, while the AuNCs provide autofluorescence properties and antioxidant catalytic activity against harmful reactive oxygen species (ROS) such as hydrogen peroxide (H2O2) and against methemoglobin (metHb) conversion.
