High-Resolution Magic-Angle Spinning NMR Spectroscopy for Evaluation of Cell Shielding by Virucidal Composites Based on Biogenic Silver Nanoparticles, Flexible Cellulose Nanofibers and Graphene Oxide.

Antiviral and non-toxic effects of silver nanoparticles onto cells infected with coronavirus were evaluated in this study using High-Resolution Magic-Angle Spinning Nuclear Magnetic Resonance (HR-MAS NMR) spectroscopy. Silver nanoparticles were designed and synthesized using an orange flavonoid-hesperetin (HST)-for reduction of silver(I) and stabilization of as obtained nanoparticles. The bio-inspired process is a simple, clean, and sustainable way to synthesize biogenic silver nanoparticles (AgNP@HST) with diameters of ∼20 nm and low zeta potential (-40 mV), with great colloidal stability monitored for 2 years.

Multifunctional coatings of exfoliated and reassembled graphite on cellulosic substrates.

Exfoliated and reassembled graphite (ERG) forms macroscopic, high aspect ratio (1 : >10) and highly conductive coating layers that are strongly adherent to paper, wood, cloth, ceramic and other substrates. The coating precursor is an aqueous dispersion of graphite that exfoliates spontaneously in alkaline cellulose solutions, forming stable dispersions. These can be applied to the substrates by using different painting, coating and lithography techniques.

In vitro immunotoxicological assessment of a potent microbicidal nanocomposite based on graphene oxide and silver nanoparticles.

Graphene oxide (GO) and silver nanoparticles (AgNPs) can be formed into a hybrid nanomaterial, known as GOAg nanocomposite, which presents high antibacterial activity. The successful translation of this nanomaterial into medical use depends on critical information about its toxicological profile. In keeping with a Safe-by-design approach, we evaluated the immunotoxicity of GOAg using J774 and primary murine macrophages.

Triboelectricity in insulating polymers: evidence for a mechanochemical mechanism.

Transfer of reaction products formed on the surfaces of two mutually rubbed dielectric solids makes an important if not dominating contribution to triboelectricity. New evidence in support of this statement is presented in this report, based on analytical electron microscopy coupled to electrostatic potential mapping techniques. Mechanical action on contacting surface asperities transforms them into hot-spots for free-radical formation, followed by electron transfer producing cationic and anionic polymer fragments, according to their electronegativity.

Structural and morphological investigations of β-cyclodextrin-coated silver nanoparticles.

This paper describes the synthesis of silver nanoparticles using an aqueous silver nitrate solution in the presence of glucose as a reducing agent, sodium hydroxide as a reaction catalyst and β-CD as a stabilizer. The structure and the morphology associated to the stabilizing layer around the silver nanoparticles were investigated. Raman spectroscopy confirmed the nanoparticle surface modification by β-CD, demonstrating the interaction between the β-CD rim hydroxyl groups and the AgNP surface.