Entrapment of Hydrophobic Drugs in Nanoparticle Monolayers with Efficient Release into Cancer Cells

Gold nanoparticles functionalized with water-soluble zwitterionic ligands form kinetically stable complexes with hydrophobic drugs and dyes. These drugs and dyes are efficiently released into cells, as demonstrated through fluorescence microscopy and cytotoxicity assays. Significantly, there is little or no cellular uptake of particle, making these low toxicity particles promising for delivery applications.