Biological profiles of plasmonic particles modified with a cell penetrating peptide

Gold nanorods (GNRs) coated with silica shells, modified with polyethylene glycol (PEG) and finally functionalized with cell penetrating peptides (CPPs) are tested in cellular uptake and cell viability. Different silica shell thicknesses (5 and 30 nm) were chosen and samples were characterized both morphologically by TEM and DLS and optically by spectrophotometry. A murine macrophagic cellular line was used to evaluate the biological profiles of CPP-functionalized silica-coated GNRs. Their kinetics of cellular uptake were investigated at different particle concentrations and results were reported as a function of incubation time. Their cytotoxicity was addressed by a colorimetric WST-8 assay at different time points and particle concentrations. Our preliminary experiments allow us to establish the best range of conditions to prepare multifunctional cellular vehicles displaying plasmonic features for photothermal and photoacoustic applications.