Biocompatible transferrin-conjugated sodium hexametaphosphate-stabilized goldnanoparticles: synthesis, characterization, cytotoxicity and cellular uptake

Abstract

The feasibility of using gold nanoparticles (AuNPs) for biomedical applications has led toconsiderable interest in the development of novel synthetic protocols and surfacemodification strategies for AuNPs to produce biocompatible molecular probes. Thisinvestigation is, to our knowledge, the first to elucidate the synthesis and characterizationof sodium hexametaphosphate (HMP)-stabilized gold nanoparticles (Au–HMP) in anaqueous medium. The role of HMP, a food additive, as a polymeric stabilizing andprotecting agent for AuNPs is elucidated. The surface modification of Au–HMPnanoparticles was carried out using polyethylene glycol and transferrin to producemolecular probes for possible clinical applications. In vitro cell viability studies performedusing as-synthesized Au–HMP nanoparticles and their surface-modified counterparts revealthe biocompatibility of the nanoparticles. The transferrin-conjugated nanoparticles havesignificantly higher cellular uptake in J5 cells (liver cancer cells) than control cells (oralmucosa fibroblast cells), as determined by inductively coupled plasma mass spectrometry.This study demonstrates the possibility of using an inexpensive and non-toxic foodadditive, HMP, as a stabilizer in the large-scale generation of biocompatible andmonodispersed AuNPs, which may have future diagnostic and therapeutic applications.