With the advancement of nanotoxicology and nanomedicine, it has been realized that nanoparticles (NPs) interact readily with biomolecular species and other chemical and organic matter to result in biocorona formation. The field of the environmental health and safety of nanotechnology, or NanoEHS, is currently lacking significant molecular-resolution data, and we set out to characterize biocorona formation through electron microscopy imaging and circular dichroism spectroscopy that inspired a novel approach for molecular dynamics (MD) simulations of protein-NP interactions. In our present study, we developed a novel GPU-optimized coarse-grained MD simulation methodology for the study of biocorona formation, a first in the field. Specifically, we performed MD simulations of a spherical, negatively charged citrate-covered silver nanoparticle (AgNP) interacting with 15 apolipoproteins. At low ion concentrations, we observed the formation of an AgNP-apolipoprotein biocorona. Consistent with the circular dichroism (CD) spectra, we observed a decrease in α-helices coupled with an increase in β-sheets in apolipoprotein upon biocorona formation.

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Despite noteworthy progress in the fabrication of large-area graphene sheetlike nanomaterials, the vapor-based processing still requires sophisticated equipment and a multistage handling of the material. An alternative approach to manufacturing functional graphene-based films includes the employment of graphene oxide (GO) micrometer-scale sheets as precursors. However, search for a scalable manufacturing technique for the production of high-quality GO nanoscale films with high uniformity and high electrical conductivity is still continuing. Here we show that conventional dip-coating technique can offer fabrication of high quality mono- and bilayered films made of GO sheets. The method is based on our recent discovery that encapsulating individual GO sheets in a nanometer thick molecular brush copolymer layer allows for the nearly perfect formation of the GO layers via dip coating from water. By thermal reduction the bilayers (cemented by a carbon-forming polymer linker) are converted into highly conductive and transparent reduced GO films with a high conductivity up to 10 S/cm and optical transparency on the level of 90%. The value is the highest electrical conductivity reported for thermally reduced nanoscale GO films and is close to the conductivity of indium tin oxide currently in use for transparent electronic devices, thus making these layers intriguing candidates for replacement of ITO films.

We describe a simple technique to alter the shape of silver nanoparticles (AgNPs) by rolling a glass tube over them to mechanically compress them. The resulting shape change in turn induces a red-shift in the localized surface plasmon resonance (LSPR) scattering spectrum and exposes new surface area. The flattened particles were characterized by optical and electron microscopy, single nanoparticle scattering spectroscopy, and surface enhanced Raman spectroscopy (SERS). AFM and SEM images show that the AgNPs deform into discs; increasing the applied load from 0 to 100 N increases the AgNP diameter and decreases the height. This deformation caused a dramatic red shift in the nanoparticle scattering spectrum and also generated new surface area to which thiolated molecules could attach as evident from SERS measurements. The simple technique employed here requires no lithographic templates and has potential for rapid, reproducible, inexpensive and scalable tuning of nanoparticle shape, surface area, and resonance while preserving particle volume.

An organo‐main group network solid having tetrahedral phosphonium vertices was prepared from a diacetyl monomer via a straightforward cyclotrimerization reaction. The network solid composition was examined by FT‐IR spectroscopy and elemental microanalysis, revealing quantitative reaction of carbonyl moieties and a 67% degree of cross‐linking. The reaction yielded a material having a layered structure that is comprised of an amorphous polymer and which is thermally stable up to 370 °C in air with a char yield of 40% upon heating as high as 800 °C under N2. The polymer is stable to 6 M NaOH(aq) at 60 °C for 24 h and takes up only 10.63% of water by mass at room temperature. The surface morphology, as examined by AFM, revealed a very smooth as‐prepared film (RMS roughness of 3 nm). The specific surface area measured by BET analysis with N2 gas is 9 m2 g−1, indicating a type II, nonporous material. Physisorption with CO2 revealed that the phosphonium network solid has additional affinity for CO2, suggesting that such materials may have use for applications such as CO2 capture. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1620–1625