ABSTRACT
Metallic nanomaterials, which are among the most fascinating materials in modern science, exhibit unique optical, electronic, magnetic, and catalytic properties. Because of their photo-optical distinctiveness and biocompatibility, luminescent gold (Au) nanomaterials have become interesting components in bioassays. This chapter focuses on the preparation and bioapplications of polymer-stabilized Au nanoclusters (NCs), thiol-stabilized Au NCs, and luminescent Au nanoparticles (Au NPs, <2 nm). Varying the experimental conditions, such as the molar ratio of the capping agent to Au ions, allows the luminescence wavelengths of these systems to be tuned from the ultraviolet to the near-infrared. The luminescence quantum yields of Au NCs are several orders of magnitude higher than those of bulk Au and larger Au NPs. The biocompatibility of Au NCs and luminescent Au NPs has led to their application in the detection of antibodies, proteins, and metal ions, as well as in cell imaging.
