Sterically Hindered Phosphonium Salts: Structure, Properties and Palladium Nanoparticle Stabilization

A new family of sterically hindered alkyl(tri-tert-butyl) phosphonium salts (n-CnH2n+1 with n = 2, 4, 6, 8, 10, 12, 14, 16, 18, 20) was synthesized and evaluated as stabilizers for the formation of palladium nanoparticles (PdNPs), and the prepared PdNPs, stabilized by a series of phosphonium salts, were applied as catalysts of the Suzuki cross-coupling reaction. All investigated phosphonium salts were found to be excellent stabilizers of metal nanoparticles of small catalytically active size with a narrow size distribution. In addition, palladium nanoparticles exhibited exceptional stability: the presence of phosphonium salts prevented agglomeration and precipitation during the catalytic reaction.

In situ study of the thermal stability of supported Pt nanoparticles and their stabilization via atomic layer deposition overcoating

Supported Pt nanoparticle stabilization via Atomic Layer Deposition overcoating with Al2O3 has been proved to prevent particle coarsening during thermal annealing for widely spaced nanoparticles while ensuring surface accessibility for applications.

Core–shell microgels as thermoresponsive carriers for catalytic palladium nanoparticles

Responsive non-N-isopropyl acrylamide (non-NIPMA) based core–shell microgels are promising carriers for Pd nanoparticles. The core contains COOH groups to achieve better nanoparticle stabilization. The shell provides control of the catalytic activity.

Toxicity and safety study of silver and gold nanoparticles functionalized with cysteine and glutathione

This study was designed to evaluate the nano–bio interactions between endogenous biothiols (cysteine and glutathione) with biomedically relevant, metallic nanoparticles (silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs)), in order to assess the biocompatibility and fate of nanoparticles in biological systems. A systematic and comprehensive analysis revealed that the preparation of AgNPs and AuNPs in the presence of biothiols leads to nanoparticles stabilized with oxidized forms of biothiols. Their safety was tested by evaluation of cell viability, reactive oxygen species (ROS) production, apoptosis induction and DNA damage in murine fibroblast cells (L929), while ecotoxicity was tested using the aquatic model organism Daphnia magna. The toxicity of these nanoparticles was considerably lower compared to their ionic metal forms (i.e., Ag+ and Au3+). The comparison with data published on polymer-coated nanoparticles evidenced that surface modification with biothiols made them safer for the biological environment. In vitro evaluation on human cells demonstrated that the toxicity of AgNPs and AuNPs prepared in the presence of cysteine was similar to the polymer-based nanoparticles with the same core material, while the use of glutathione for nanoparticle stabilization was considerably less toxic. These results represent a significant contribution to understanding the role of biothiols on the fate and behavior of metal-based nanomaterials.

Correction: In search of bioinspired hydrogels from amphiphilic peptides: a template for nanoparticle stabilization for the sustained release of anticancer drugs

Correction for ‘In search of bioinspired hydrogels from amphiphilic peptides: a template for nanoparticle stabilization for the sustained release of anticancer drugs’ by Radha Rani Mehra et al., New J. Chem., 2019, 43, 11666–11678.

In search of bioinspired hydrogels from amphiphilic peptides: a template for nanoparticle stabilization for the sustained release of anticancer drugs

This report presents the efficiency of palmitic acid-based proteolytically stable, biocompatible hydrogelators for the sustained release of anticancer drugs.