Biosynthesis of β-D-glucan-gold nanoparticles, cytotoxicity and oxidative stress in mouse splenocytes

This study reports biosynthesis of gold-nanoparticles (AuNPs) by using beta-D-glucans isolated from the yeast Yarrowia lypolitica D1. beta-D-glucans serve as reducing and stabilizing mediators that induce the formation of AuNPs on the outer surface of the own beta-D-glucan. The systems were physicochemically characterized by ultraviolet visible (UV-Vis) spectroscopy, high-resolution transmission electron microscopy (HR-TEM), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), and dynamic light scattering (DLS) analyses. The results revealed the generation of AuNPs with quasi-spherical shape or large one dimension (1D) gold-nanostructures (AuNSs) depending on the HAuCl4 concentration. A cytotoxic study was assessed in mouse splenocytes. Contrary to that expected, important cytotoxicity was found in all beta-D-gluc+AuNPs systems by an oxidative stress increase. This study discusses the cytotoxic mechanism, suggesting that the resulting beta-D-gluc+AuNPs systems may not be candidates for the formulation of immunostimulants or nanocarriers for biomedical applications. (C) 2019 Elsevier B.V. All rights reserved.