Dendronized Anionic Gold Nanoparticles: Synthesis, Characterization and Antiviral Activity

Abstract

Anionic carbosilane dendrons decorated with sulfonate functions and with a thiol moiety at the focal point have been used to synthesize water soluble gold nanoparticles (AuNPs) by direct reaction of dendrons, gold precursor and reducing agent in water and also by place-exchange reaction. These nanoparticles have been characterized by nuclear magnetic resonance (NMR), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), UV, elemental analysis, and Z potential. Also, the interacting ability of the anionic sulfonate functions was investigated by electron paramagnetic resonance (EPR) using copper(II) as a probe. It was found that the different structures and conformations of the AuNPs modulate the availability of sulfonate and thiol groups to be complexed by copper(II). Toxicity assays of AuNPs showed that those produced by direct reaction were less toxic than those obtained by ligand exchange. Inhibition of HIV-1 infection was higher for dendronized AuNPs than for dendrons.