Preparation and Biomedical Applications of Gold Nanocluster

Gold nanoclusters (AuNCs) have attracted considerable attentions as a novel class of fluorophores, due to their unique physical and chemical properties. These properties include convenient synthesis, ultra-small size, outstanding fluorescent properties, excellent optical/colloidal stability and biocompatibility. In this review, we summarize the synthesis strategies for the AuNCs, which involve template method, etching method, reversible phase transfer method, as well as dynamic control method. We also focus on recent advances on applications of the AuNCs in biomedicine, where they are used as fluorescent labels in biosensor, bio-imaging and multifunctional drug delivery systems. In particular, the photothermal effect of the AuNCs can be utilized to light-trigger controlled drug release for carrying on photothermal therapy. Finally, we discuss the prospects and challenges facing the AuNCs in their synthesis strategies and biological applications.