In Situ Ligand-Directed Growth of Gold Nanoparticles in Biological Tissues

Fundamental understandings and precise control of nanoparti-cle growth in the complex biological environment are crucial to broadening their potential applications in tissue imaging. Herein, we report that glutathione (GSH), a widely used cap-ping ligand for precise control of the size of gold nanoparticle (AuNP) down to single-atom level in test tubes, can also be used to direct the selective growth of the AuNPs in the mito-chondria of renal tubule cells as well as hippocampus cells in the tissues. Precise control of this growth process can lead to formation of both ultrasmall AuNPs with near-infrared lumi-nescence and large plasmonic AuNPs. The observed selective growth of the AuNPs is likely due to unique GSH storage function of the mitochondria. Using a different ligand, β-glucose thiol, we also found that the brush border of intestine for glucose absorption became the major site for the growth of luminescent AuNPs. These findings suggest that selective growth of AuNPs in the biological tissues can in...