Regulating the Optical Properties of Gold Nanoclusters for Biological Applications

[Image: see text] Gold nanoclusters are promising optically functional materials because of their attractive optical properties, such as luminescence, two-photon absorption, photothermal conversion, and photodynamics. Regulating the optical functions of gold nanoclusters and improving their performance have attracted wide interest in biological applications. In this Review, we introduce the principles to manipulate both the intrinsic optical properties and the apparent optical performance of gold nanoclusters. Manipulating the surface ligands and compounding with other nanomaterials are facile and efficient strategies. Based on the regulated optical properties, the gold nanoclusters can be well applied in various biomedical applications from multimodal bioimaging toward theranostics. By correlating structures and optical properties, we expect a better utilization of the optical gold nanoclusters in the biological field.