Introduction of nanoscale positive controls for nanotoxicology: A new aspect of utilization of stability-enhanced Gold-Polyethyleneimine conjugates (Au-PEIs)

We report on a stability-enhanced suspension of gold-polyethyleneimine conjugates (Au-PEIs), prepared by an optimized synthetic process. The physicochemical properties of Au-PEIs were characterized using several analytical instruments including dynamic light scattering, UV-Vis, transmission electron microscope, and atomic force microscope. The nanoparticles in this report have shown excellent colloidal stability to avoid particle-particle interactions in various aqueous environments, which is very critical to become effective materials in nanomedicine. Most importantly, the cytotoxicity of Au-PEIs has been investigated by cell viability assays using a variety of cell lines (CHO K1, HeLa, and A549) and has significant toxicity in common, appeared to be more toxic than a traditional positive control (CdSO
4
). This suggests the potential for use as a universal nanoscale positive control material in nanotoxicity studies.