Study of the premicellar state in aqueous solutions of sodium dodecyl sulfate by nuclear magnetic resonance diffusion

Self-diffusion coefficients of sodium dodecyl sulfate (SDS) were measured in aqueous solutions in the premicellar range of the SDS concentrations 7–34.7 mM and temperatures 30–90°C. Average effective hydrodynamic radii and aggregation numbers of SDS in the premicellar region were determined. At C CMC, the increase of temperature leads to decrease in the effective hydrodynamic radii and the average aggregation numbers. At C > > CMC, it is impossible to reach the monomeric state by increasing the temperature

Effect of rotating magnetic field on the diffusivity of ethylammonium nitrate ionic liquid confined between micrometer-spaced glass plates

We studied changes in the diffusion coefficients in layers of EAN confined between glass plates, placed in a strong magnetic field with a magnetic flux density B0, and rotated around the axis directed along and normal to B0. Under the rotational conditions along B0, the diffusion coefficient decreases with time after placement in the magnetic field at the same rate as for a static sample, observed previously (Filippov and Antzutkin, Phys. Chem. Chem. Phys. 2018. 20. 6316). However, when the EAN layers are rotating around the axis perpendicular to B0, the duration of exposure to the magnetic field does not affect the diffusion coefficient until the rotation stops. On the other hand, the diffusivity after extended exposure to a static magnetic field increases as the sample starts to rotate around the axis perpendicular to B0. The observed effects are due to either the periodic change in the orientation of the thin surface layers of EAN or inhomogeneity of B0 in the sample due to the B0 fluctuation

Neutralizing activity of sera from sputnik v-vaccinated people against variants of concern (VOC: B.1.1.7, B.1.351, P.1, B.1.617.2, B.1.617.3) and Moscow endemic SARS-CoV-2 variants

Since the beginning of the 2021 year, all the main six vaccines against COVID-19 have been used in mass vaccination companies around the world. Virus neutralization and epidemiological efficacy drop obtained for several vaccines against the B.1.1.7, B.1.351 P.1, and B.1.617 genotypes are of concern. There is a growing number of reports on mutations in receptor-binding domain (RBD) increasing the transmissibility of the virus and escaping the neutralizing effect of antibodies. The Sputnik V vaccine is currently approved for use in more than 66 countries but its activity against variants of concern (VOC) is not extensively studied yet. Virus-neutralizing activity (VNA) of sera obtained from people vaccinated with Sputnik V in relation to internationally relevant genetic lineages B.1.1.7, B.1.351, P.1, B.1.617.2, B.1.617.3 and Moscow endemic variants B.1.1.141 (T385I) and B.1.1.317 (S477N, A522S) with mutations in the RBD domain has been assessed. The data obtained indicate no significant differences in VNA against B.1.1.7, B.1.617.3 and local genetic lineages B.1.1.141 (T385I), B.1.1.317 (S477N, A522S) with RBD mutations. For the B.1.351, P.1, and B.1.617.2 statistically significant 3.1-, 2.8-, and 2.5-fold, respectively, VNA reduction was observed. Notably, this decrease is lower than that reported in publications for other vaccines. However, a direct comparative study is necessary for a conclusion. Thus, sera from “Sputnik V”-vaccinated retain neutralizing activity against VOC B.1.1.7, B.1.351, P.1, B.1.617.2, B.1.617.3 as well as local genetic lineages B.1.1.141 and B.1.1.317 circulating in Moscow. © 2021 by the authors. Licensee MDPI, Basel, Switzerland