Impacts of Differentially Shaped Silver Nanoparticles with Increasingly Complex Hydrophobic Thiol Surface Coatings in Small-Scale Laboratory Microcosms.

We investigated the impacts of spherical and triangular-plate-shaped lipid-coated silver nanoparticles (AgNPs) designed to prevent surface oxidation and silver ion (Ag) dissolution in a small-scale microcosm to examine the role of shape and surface functionalization on biological interactions. Exposures were conducted in microcosms consisting of algae, bacteria, crustaceans, and fish embryos. Each microcosm was exposed to one of five surface chemistries within each shape profile (at 0, 0.

Silver Nanoparticles Stable to Oxidation and Silver Ion Release Show Size-Dependent Toxicity In Vivo.

Silver nanoparticles (AgNPs) are widely used in commerce, however, the effect of their physicochemical properties on toxicity remains debatable because of the confounding presence of Ag ions. Thus, we designed a series of AgNPs that are stable to surface oxidation and Ag ion release. AgNPs were coated with a hybrid lipid membrane comprised of L-phosphatidylcholine (PC), sodium oleate (SOA), and a stoichiometric amount of hexanethiol (HT) to produce oxidant-resistant AgNPs, Ag-SOA-PC-HT.

Size-Dependent Interactions of Lipid-Coated Gold Nanoparticles: Developing a Better Mechanistic Understanding Through Model Cell Membranes and in vivo Toxicity.

Introduction: Humans are intentionally exposed to gold nanoparticles (AuNPs) where they are used in variety of biomedical applications as imaging and drug delivery agents as well as diagnostic and therapeutic agents currently in clinic and in a variety of upcoming clinical trials. Consequently, it is critical that we gain a better understanding of how physiochemical properties such as size, shape, and surface chemistry drive cellular uptake and AuNP toxicity in vivo. Understanding and being able to manipulate these physiochemical properties will allow for the production of safer and more efficacious use of AuNPs in biomedical applications.

A hybrid lipid membrane coating "shape-locks" silver nanoparticles to prevent surface oxidation and silver ion dissolution.

The controlled synthesis of stable silver nanoparticles (AgNPs), that do not undergo surface oxidation and Ag ion dissolution, continues to be a major challenge. Here the synthesis of robust hybrid lipid-coated AgNPs, comprised of l-α-phosphatidylcholine (PC) membranes anchored by a stoichiometric amount of long-chained hydrophobic thiols and sodium oleate (SOA) as hydrophobic binding partners, that do not undergo surface oxidation and Ag ion dissolution, is described. UV-Visible (UV-Vis) spectroscopy, transmission electron microscopy (TEM), and inductively coupled plasma mass spectrometry (ICP-MS) demonstrate that in the presence of strong oxidants, such as potassium cyanide (KCN), the hybrid lipid-coated AgNPs are stable and do not undergo surface oxidation even in the presence of membrane destabilizing surfactants.