Electroceutical fabric lowers zeta potential and eradicates coronavirus infectivity upon contact

Coronavirus with intact infectivity attached to PPE surfaces pose significant threat to the spread of COVID-19. We tested the hypothesis that an electroceutical fabric, generating weak potential difference of 0.5 V, disrupts the infectivity of coronavirus upon contact by destabilizing the electrokinetic properties of the virion. Porcine respiratory coronavirus AR310 particles (105) were placed in direct contact with the fabric for 1 or 5 min. Following one minute of contact, zeta potential of the porcine coronavirus was significantly lowered indicating destabilization of its electrokinetic properties. Size-distribution plot showed appearance of aggregation of the virus. Testing of the cytopathic effects of the virus showed eradication of infectivity as quantitatively assessed by PI-calcein and MTT cell viability tests. This work provides the rationale to consider the studied electroceutical fabric, or other materials with comparable property, as material of choice for the development of PPE in the fight against COVID-19.

Study of Electrokinetic Properties of Magnetite – Silica Core – Shell Nanoparticles

In this work, the electrokinetic properties of Fe3O4 nanoparticles modified with various alkoxysilanes (tetraethoxysilane and 3-aminopropyltriethoxysilane) in various media were investigated. The determined values of the zeta potential of the Fe3O4/SiO2 samples indicate the complete coverage of nanoparticles with a tetraethoxysilane shell, as well as in the case of the Fe3O4/aminopropyltriethoxysilane. The data obtained on the zeta-potentials of modified nanoparticles with various ligands make it possible to predict the efficiency of subsequent functionalization by target molecules. A decisive role in the study of surface properties is played by cleaning from low molecular weight impurities that can screen the surface of nanoparticles or bind with an indifferent electrolyte. Thus, dispersion on a magnetic stirrer leads to an increase in the sorption capacity of the sample in comparison with ultrasonic dispersion, which causes irreversible destruction of the core-shell nanoparticle structure due to an increase in temperature and pressure in the cavities. This opens the prospective for practical application of modified nanoparticles for creation of tailored composite materials.

The influence of fucoidan on stability, adsorption and electrokinetic properties of ZnO and TiO2 suspensions

Stabilization of nano-oxide suspensions is a very important process. Nowadays, synthetic polymers are used to increase stability of the colloidal systems. However, this solution is not ecological and incompatible with the principles of green chemistry. Instead of synthetic polymers, their natural counterparts can be used. Herein, we present the use of natural bioactive polysaccharide—fucoidan as a stabilizer of nano-zinc(II) and nano-titanium(IV) oxide suspensions. These two oxides are commercially available and are widely used in the cosmetic and pharmaceutical industries. The turbidimetric studies (Turbiscan Lab) showed that the addition of fucoidan leads to the increase of stability and that the effect depends on the polymer concentration. To fully describe the systems’ stability, the adsorption (UV–Vis and FT-IR/PAS) and the electrokinetic properties (zeta potential and surface charge density) were studied. The obtained results indicate that fucoidan adsorbs by the electrostatic and non-electrostatic interactions on the used oxides forming the tight adsorption layer. The following paper thoroughly explains the stabilization mechanism of fucoidan toward the nano-oxide suspensions. Moreover, the presented results could be useful in the preparation of new cosmetic and pharmaceutical products containing nano-oxides.