Synthesis, optical and microscopical characterization of albumin/porous silica/gold nanorods

We describe the synthesis of novel hybrid nanoparticles composed of a gold nanorods core and a bovine serum albumin-conjugated porous silica shell. The pores of the porous silica shell are loaded with the cytotoxic surfactant cetrimonium bromide. Throughout the various steps of the synthesis, these nanoparticles exhibit excellent light extinction in a near infrared window around 700 - 900 nm, and good colloidal stability in aqueous environment. On replacement of the bovine serum albumin and cetrimonium bromide with functional macromolecules (e. g. antibodies) and appropriate drugs, this architecture may find application in a variety of biomedical applications including optical and photoacoustic diagnoses and imaging, photothermal and photoacoustic therapies and controlled drug release.