Physicochemical Properties of Protein-Coated Gold Nanoparticles in Biological Fluids and Cells before and after Proteolytic Digestion

Munish Chanana, Pilar Rivera-Gil, Miguel A. Correa-Duarte, Luis M. Liz-Marzán, and Wolfgang J. Parak

Angew. Chem. Int. Ed. 2013, 52, 4179‒4183

What’s going on in there?! Little is known about the fate of nanoparticles (NPs) after their internalization by cells and organisms. Protein-coated gold NPs were used to study the physicochemical properties of NPs in extra- and intracellular fluids. These potential vehicles for enzymatic drug delivery were highly stable at pH 7.4 in the presence of salts and free proteins, but agglomerated reversibly under acidic conditions (see picture).