title: The Impact of Surface Ligands and Synthesis Method on the Toxicity of Glutathione-Coated Gold Nanoparticles.
abstract: Gold nanoparticles (AuNPs) are increasingly used in biomedical applications, hence understanding the processes that affect their biocompatibility and stability are of significant interest. In this study, we assessed the stability of peptide-capped AuNPs and used the embryonic zebrafish (Danio rerio) as a vertebrate system to investigate the impact of synthesis method and purity on their biocompatibility. Using glutathione (GSH) as a stabilizer, Au-GSH nanoparticles with identical core sizes were terminally modified with Tryptophan (Trp), Histidine (His) or Methionine (Met) amino acids and purified by either dialysis or ultracentrifugation. Au-GSH-(Trp)2purified by dialysis elicited significant morbidity and mortality at 200 μg/mL, Au-GSH-(His)2induced morbidity and mortality after purification by either method at 20 and 200 μg/mL, and Au-GSH-(Met)2caused only sublethal responses at 200 μg/mL. Overall, toxicity was significantly reduced and ligand structure was improved by implementing ultracentrifugation purifications at several stages during the multi-step synthesis and surface modification of Au-GSH nanoparticles. When carefully synthesized at high purity, peptide-functionalized AuNPs showed high biocompatibility in biological systems.
authors.affiliation: Department of Environmental and Molecular Toxicology, Oregon State University, 1007 ALS Building, Corvallis, OR97331, USA.
authors.forename: Bryan
authors.initials: B
authors.lastname: Harper
authors.affiliation: Department of Environmental and Molecular Toxicology, Oregon State University, 1007 ALS Building, Corvallis, OR97331, USA.
authors.forename: Federico
authors.initials: F
authors.lastname: Sinche
authors.affiliation: Departmentof Chemistry, Portland State University, 1719 SW 10th Ave., Portland, OR 97201, USA.
authors.forename: Rosina Ho
authors.initials: RH
authors.lastname: Wu
authors.affiliation: Departmentof Chemistry, Portland State University, 1719 SW 10th Ave., Portland, OR 97201, USA.
authors.forename: Meenambika
authors.initials: M
authors.lastname: Gowrishankar
authors.affiliation: Departmentof Chemistry, Portland State University, 1719 SW 10th Ave., Portland, OR 97201, USA.
authors.forename: Grant
authors.initials: G
authors.lastname: Marquart
authors.affiliation: Departmentof Chemistry, Portland State University, 1719 SW 10th Ave., Portland, OR 97201, USA.
authors.forename: Marilyn
authors.initials: M
authors.lastname: Mackiewicz
authors.affiliation: Department of Environmental and Molecular Toxicology, Oregon State University, 1007 ALS Building, Corvallis, OR97331, USA.
authors.forename: Stacey L
authors.initials: SL
authors.lastname: Harper
keywords: biocompatibility; glutathione; gold; nanoparticle; nanotoxicity; purity; synthesis; zebrafish