Synergistic neurological threat from Сu and wood smoke particulate matter.

Trace metal Cu and carbonaceous airborn particulate matter (PM) are dangerous neuropollutants. Here, the ability of Cu to modulate the neurotoxicity caused by water-suspended wood smoke PM preparations (SPs) and vice versa was examined using presynaptic rat cortex nerve terminals. Interaction of Cu and SPs, changes of particle size and surface properties were shown in the presence of Cu using microscopy, DLS, and IR spectroscopy.

Disposable facemask waste combustion emits neuroactive smoke particulate matter.

Tremendous deposits of disposable medical facemask waste after the COVID-19 pandemic require improvement of waste management practice according to WHO report 2022, moreover facemasks are still in use around the world to protect against numerous airborne infections. Here, water-suspended smoke preparations from the combustion of disposable medical facemasks (polypropylene fibers) were collected; size, zeta potential, surface groups of smoke particulate matter were determined by dynamic light scattering, FTIR and Raman spectroscopy, and their optical properties were characterized. Neurochemical study using nerve terminals isolated from rat cortex revealed a significant decrease in the initial rate of the uptake/accumulation of excitatory and inhibitory neurotransmitters, L-[C]glutamate and [H]GABA, and exocytotic release, and also an increase in the extracellular level of these neurotransmitters.

The effect of 2D tungsten disulfide nanoparticles on Lewis lung carcinoma cells .

The unique physicochemical properties of modern two-dimensional (2D) nanomaterials with graphene-like structures make them promising candidates for biology and medicine purposes. In this article, we investigate the influence of the two-dimensional tungsten disulfide (2D WS) water suspension nanoparticles obtained by an improved mechanochemical method from powdered WS on morphological and structural characteristics of Lewis lung carcinoma cells using FT-IR, Raman spectroscopy, and confocal microscopy. The characterization of the 2D WS nanoparticles by different physical methods is given also.

Amphiphilic anti-SARS-CoV-2 drug remdesivir incorporates into the lipid bilayer and nerve terminal membranes influencing excitatory and inhibitory neurotransmission.

Remdesivir is a novel antiviral drug, which is active against the SARS-CoV-2 virus. Remdesivir is known to accumulate in the brain but it is not clear whether it influences the neurotransmission. Here we report diverse and pronounced effects of remdesivir on transportation and release of excitatory and inhibitory neurotransmitters in rat cortex nerve terminals (synaptosomes) in vitro.

A comparative study of wood sawdust and plastic smoke particulate matter with a focus on spectroscopic, fluorescent, oxidative, and neuroactive properties.

Here, water-suspended smoke aerosol preparation was synthesized from biomass-based fuel, i.e., a widespread product for residential heating, wood sawdust (WP) (pine, poplar, and birch mixture), and its properties were compared in parallel experiments with the smoke preparation from plastics (PP).

Dual effect of 2D WS nanoparticles on the lysozyme conformation.

In the present work we studied the effect of 2D WS nanoparticles on the conformational changes in lysozyme protein at different pH values (2.0-11.5).

Characterization of thymine microcrystals by CARS and SHG microscopy.

Identification of chemically homologous microcrystals in a polycrystal sample is a big challenge and requires developing specific highly sensitive tools. Second harmonic (SHG) and coherent anti-Stokes Raman scattering (CARS) spectroscopy can be used to reveal arrangement of thymine molecules, one of the DNA bases, in microcrystalline sample. Strong dependence of CARS and SHG intensity on the orientation of the linear polarization of the excitation light allows to obtain high resolution images of thymine microcrystals by additionally utilizing the scanning microscopy technique.

Recognition of Spatial Distribution of CNT and Graphene in Hybrid Structure by Mapping with Coherent Anti-Stokes Raman Microscopy.

The shape of coherent anti-Stokes Raman scattering (CARS) spectral line depends on the ratio of the vibrational and electronic contributions to the third-order susceptibility of the material. The G-mode (1590 cm) of graphene and carbon nanotubes (CNTs) exhibits opposite features in the CARS spectrum, showing "dip" and "peak," respectively. Here, we consider the CARS spectra of graphene and carbon nanotubes in terms of Fano formalism describing the line shapes of CARS resonances.

Mechanochemical synthesis of carbon-stabilized Cu/C, Co/C and Ni/C nanocomposites with prolonged resistance to oxidation.

Metal-carbon nanocomposites possess attractive physical-chemical properties compared to their macroscopic counterparts. They are important and unique nanosystems with applications including in the future development of nanomaterial enabled sensors, polymer fillers for electromagnetic radiation shields, and catalysts for various chemical reactions. However, synthesis of these nanocomposites typically employs toxic solvents and hazardous precursors, leading to environmental and health concerns.

Heat Shock Proteins in the "Hot" Mitochondrion: Identity and Putative Roles.

The mitochondrion is known as the "powerhouse" of eukaryotic cells since it is the main site of adenosine 5'-triphosphate (ATP) production. Using a temperature-sensitive fluorescent probe, it has recently been suggested that the stray free energy, not captured into ATP, is potentially sufficient to sustain mitochondrial temperatures higher than the cellular environment, possibly reaching up to 50 °C. By 50 °C, some DNA and mitochondrial proteins may reach their melting temperatures; how then do these biomolecules maintain their structure and function? Further, the production of reactive oxygen species (ROS) accelerates with temperature, implying higher oxidative stresses in the mitochondrion than generally appreciated.

2D-BN nanoparticles as a spectroscopic marker and drug delivery system with protection properties.

An application of 2D-BN nanoparticles as a spectroscopic marker, weak luminescent marker and anticancer drug (doxorubicin, DOX) delivery system with protection properties was studied for the LNCaP strains of cancer cells using FTIR and Raman spectroscopy for analysing the cancer cells, cells with BN, the cancer cells with DOX, and the cancer cells with BN nanoparticles loaded by DOX. Study of IR absorption and Raman spectra of the LNCaP strains of cancer cells incubated with 2D-BN nanoparticles for 1 hour showed that the 2D-BN nanoparticles could pass through the cell membrane and localize inside the membrane or close to the membrane in the cytoplasm of the cells. We registered the spectra of the disturbed lipids during the DOX-2D-BN passing through the membrane.

Vibrational spectra of DNA in the confined interglobular volume of photonic crystal.

The impact of confinement of DNA molecules in a limited volume of the cavity of photonic crystals (PC) on the vibrational properties of the DNA molecule and its conformation is studied. According to our preliminary study, the aqueous shell is removed when the DNA molecules are infiltrated into the PC cavities. Raman scattering (RS) DNA marker lines showed a dramatic conformational change of DNA in the PC cavities and the appearance of new unknown conformational states.

Liquid exfoliation of mechanochemically nanostructured tungsten disulfide to a graphene-like state.

The possibility of the efficient preparation of graphene-like 1H-WS by the primary solventless nanostructuration of bulk 2H-WS by means of its mechanochemical treatment in the presence of a chemically inert agent (NaCl) and the subsequent liquid exfoliation of the nanostructured 2H-WS in an organic solvent is shown for the first time. The shear stresses generated during the grinding of the WS/NaCl mixture caused the formation of WS particles with a reduced number of layers, while the stresses normal to their surface led to their cracking and a significant reduction in lateral size. The graphene-like morphology of the 1H-WS nanoparticles in the prepared dispersions is confirmed by atomic force microscopy and Raman spectroscopy.

Graphene-Enhanced Raman Scattering from the Adenine Molecules.

An enhanced Raman scattering from a thin layer of adenine molecules deposited on graphene substrate was detected. The value of enhancement depends on the photon energy of the exciting light. The benzene ring in the structure of adenine molecule suggests π-stacking of adenine molecule on top of graphene.

Quantum-Chemical Calculation and Visualization of the Vibrational Modes of Graphene in Different Points of the Brillouin Zone.

Different notations of graphene irreducible representations and optical modes could be found in the literature. The goals of this paper are to identify the correspondence between available notations, to calculate the optical modes of graphene in different points of the Brillouin zone, and to compare them with experimental data obtained by Raman and coherent anti-Stokes Raman scattering (CARS) spectroscopy. The mechanism of the resonance enhancement of vibration modes of the molecules adsorbed on graphene in CARS experiments is proposed.

Optical Properties of Pyrolytic Carbon Films Versus Graphite and Graphene.

We report a comparative study of optical properties of 5-20 nm thick pyrolytic carbon (PyC) films, graphite, and graphene. The complex dielectric permittivity of PyC is obtained by measuring polarization-sensitive reflectance and transmittance spectra of the PyC films deposited on silica substrate. The Lorentz-Drude model describes well the general features of the optical properties of PyC from 360 to 1100 nm.

Graphene-enhanced Raman spectroscopy of thymine adsorbed on single-layer graphene.

Graphene-enhanced Raman scattering (GERS) spectra and coherent anti-Stokes Raman scattering (CARS) of thymine molecules adsorbed on a single-layer graphene were studied. The enhancement factor was shown to depend on the molecular groups of thymine. In the GERS spectra of thymine, the main bands are shifted with respect to those for molecules adsorbed on a glass surface, indicating charge transfer for thymine on graphene.

Angular shaping of fluorescence from synthetic opal-based photonic crystal.

Spectral, angular, and temporal distributions of fluorescence as well as specular reflection were investigated for silica-based artificial opals. Periodic arrangement of nanosized silica globules in the opal causes a specific dip in the defect-related fluorescence spectra and a peak in the reflectance spectrum. The spectral position of the dip coincides with the photonic stop band.

Coherent anti-Stokes Raman scattering enhancement of thymine adsorbed on graphene oxide.

Coherent anti-Stokes Raman scattering (CARS) of carbon nanostructures, namely, highly oriented pyrolytic graphite, graphene nanoplatelets, graphene oxide, and multiwall carbon nanotubes as well CARS spectra of thymine (Thy) molecules adsorbed on graphene oxide were studied. The spectra of the samples were compared with spontaneous Raman scattering (RS) spectra. The CARS spectra of Thy adsorbed on graphene oxide are characterized by shifts of the main bands in comparison with RS.

Spectroscopic study of proflavine adsorption on the carbon nanotube surface.

Despite the fact that non-covalent interactions between various aromatic compounds and carbon nanotubes are being extensively investigated now, there is still a lack of understanding about the nature of such interactions. The present paper sheds light on one of the possible mechanisms of interaction between the typical aromatic dye proflavine and the carbon nanotube surface, namely, π-stacking between aromatic rings of these compounds. To investigate such a complexation, a qualitative analysis was performed by means of ultraviolet visible, infrared, and nuclear magnetic resonance spectroscopy.

p-Nitrobenzoic acid adsorption on nanostructured gold surfaces investigated by combined experimental and computational approaches.

Adsorption of guest molecules on host surfaces can lead to dramatic changes in the spectral properties of the guest. One such effect is surface-enhanced infrared absorption (SEIRA), observed when the guest is adsorbed on, for example, thin films, metal surfaces, or nanotubes. p-Nitrobenzoic acid (p-NBA) exhibits a SEIRA effect when adsorbed on Ag and Au.

Oxovanadium ions bind transfer RNA at multiple sites.

Oxovanadium compounds exert preventive effects against chemical carcinogenesis in animals and form complexes with DNA and RNA in vivo. This study was designed to examine the interaction of transfer RNA (tRNA) with VO(2+) and VO₃⁻ ions in aqueous solution at physiological pH, with constant a tRNA concentration of 12.5 mM and different vanadium/RNA (P) (P = phosphate) molar ratios (r) of 1:60 to 1:2.

Effect of a pH change on the conformational stability of the modified nucleotide queuosine monophosphate.

The naturally occurring modified nucleotide queuosine 5'-monophosphate (QMP) related to biochemical regulatory pathways in the cell was investigated using quantum chemical approaches. The relative stability of biologically relevant conformations of QMP in solvent under a pH change was predicted at the BVP86/TZVP and MP2/TZVP levels of theory. Hydrogen bonding in QMP was studied using Bader's approach.

FTIR spectroscopy studies of nucleic acid damage.

Fourier transform infrared (FTIR) spectra of RNA isolated from tumour brain (glioma) and DNA isolated from low-dose gamma-irradiated epididymis cells of rats from the Chernobyl accident zone have been investigated in the 700-4000 cm(-1) region. The total absorbed radiation doses were equal to or less than 57 cGy. Observed changes in the FTIR spectra represent the damage in the primary, secondary and tertiary structure of nucleic acid, which seem to be connected with modification of bases and sugars, and redistribution of the H-bond network.