Highly Fluorescent Gene Carrier Based on Ag–Au Alloy Nanoclusters

For systemic delivery of gene, gold nanoparticles (GNPs) have been exploited as novel gene carriers because of the excellent characteristics for "visible" in intracellular trafficking. Herein, a highly fluorescent gene carrier was prepared by conjugating polyethylenimines on Ag-Au alloy nanoclusters. This carrier exhibited remarkable high gene transfection efficiencies and relatively low cytotoxicity toward B16F10, HeLa, and CHO cells. More interestingly, the high fluorescent Ag-Au-PEI conjugates showed high quantum yield of 14.56%, which is much higher than most of the reported gold nanocluster-based quantum dots and Ag-Au-PEI possessed bioimaging capacity both in vitro and in vivo.