Toxicity of Gold Nanoparticles Functionalized with Cationic and Anionic Side Chains

Abstract

The structure and properties of gold nanoparticles make them useful for a wide array of biological application. Toxicity, however, has been observed at high concentrations using these systems. MTT, hemolysis, and bacterial viability assays were used to explore differential toxicity among the cell types used, using 2 nm core particles. These studies show that cationic particles are moderately toxic, whereas anionic particles are quite nontoxic. Concentration-dependent lysis mediated by initial electrostatic binding was observed in dye release studies using lipid vesicles, providing the probable mechanism for observed toxicity with the cationic MMPCs.

Fluorinated and Charged Hydrogenated Alkanethiolates Grafted on Gold: Expanding the Diversity of Mixed-Monolayer Nanoparticles for Biological Applications

“…We observed that the negatively charged NP-MDDS/F6/ Bodipy showed limited cytotoxicity to moderate toxicity in a concentration dependent manner with 38% of the cell population labeled with both NPs and PI indicating disruption of the cell membrane at a concentration of 0.2 mg/mL ( Figure S24). In an assessment of NPs toxicity toward mammalian cells, Rotello and co-workers 47 reported that anionic NPs, featuring, for instance, carboxylate groups on their surface, are less toxic than cationic NPs, with the anionic displaying LC 50 values about 1 order of magnitude higher than the cationic. Surprisingly, we found that the positively charged NP-TMDA/F6/Bodipy showed at maximum 7% of PI positive cells after exposure to the highest tested NPs concentration of 0.2 mg/mL ( Figure S25).…”

Gold nanoparticles and ions – friends or foes? As they are seen by human cells U-937 and HL-60

“…Thus, cationic gold nanospheres (2 nm in diameter) were found to be toxic, whereas anionic nanoparticles were not toxic to the same cell line. [35] Equally important seems to be their size, for example, 1.4 nm gold nanospheres resulted in necrosis, damage to mitochondria and induction of oxidative stress, while 15 nm gold nanospheres did not harm the cells. [32] Many authors focused on the impact of physical and chemical parameters, such as particle size, shape or charge, while the effect of a degree of nanoparticle purification on the biological model was not tested.…”

A fluorescein-based chemodosimeter for selective gold(III) ion monitoring in aqueous media and living systems

“…However, products obtained by way of gold catalysis-often candidates for certain drugs and medicines-may nevertheless contain gold impurities and thus pose serious health and environmental concerns. As other recent studies have invariably shown, the accumulation of gold ions, despite their diverse biological and chemical properties, indeed generates toxicity in living organisms [7,8]. As expanding research using gold ions comes to recognize these realities, another strand of research has sought to develop efficient, practical analytical methods of ascertaining gold ion levels in both chemical and biological environments.…”