Biomolecule-assisted synthesis of water-soluble silver nanoparticles and their biomedical applications.

The application of nanoparticles in the biomedical field is an exciting interdisciplinary research area in current materials science. In the present study, size-tunable and water-soluble noble metal silver nanoparticles (Ag NPs) have been successfully synthesized with the assistance of glutathione (GSH). The as-synthesized Ag NPs are ready to bind covalently with a model protein (bovine serum albumin) in mild conditions. The optical property of surface-modifiable Ag NPs was extremely sensitive to their size and the surface modification, suggesting a potential in the biomedical analysis and detection. Furthermore, Ag NPs with an average diameter of ca. 6 nm effectively suppress the proliferation of human leukemic K562 cells in the dose- and time-dependent manners, suggesting the promising potential of Ag NPs in cancer therapy.