Physicochemical Properties Influence the Cytotoxicity Level of Gold Nanoparticles

Abstract

Gold nanoparticles (AuNPs) can be used for a variety of biological applications, including medical treatment and drug transport [1]. A wide AuNPs application range arises the necessity to broaden studies of parameters that affect their toxicity. Their biocompatibility can differ in relation to synthesis method and the used chemical for their stabilization, but also their physicochemical properties e.g. size and shape [2]. Laser ablation of a gold target could be considered as “green” synthesis, since no chemical or toxic waste is produced [3]. Our goal was to analyze the physicochemical properties and cytotoxicity impact of two “green” AuNPs synthesized under different laser parameters. The analyzed AuNPs were characterized by UV–visible spectroscopy analysis, dynamic light scattering (DLS), and ζ-potential (ZP) measurements at two time points to additionally asses their stability. Cytotoxic concentration of AuNPs on the human cell line MRC-5 was evaluated by viability assay (XTT). Our results indicated that cytotoxic effects arise parallel to elevation of applied concentration. AuNPs with UV spectra maximum at lower wavelengths, higher ζ-potential and hydrodynamic diameter, and higher stability displayed higher levels of cytotoxicity. A safe application depends on AuNPs' biocompatibility that relies on their unique physical and chemical properties that influence their stability. Future perspectives, which include functionalization and AuNPs coating, could additionally reduce their toxicity by altering their physicochemical properties and focus their specific applications.