Radiothermal Emission of Nanoparticles with a Complex Shape as a Tool for the Quality Control of Pharmaceuticals Containing Biologically Active Nanoparticles

Abstract

It has recently been shown that the titer of the SARS-CoV-2 virus decreases in a cell culture when the cell suspension is irradiated with electromagnetic waves at a frequency of 95 GHz. We assumed that a frequency range in the gigahertz and sub-terahertz ranges was one of the key aspects in the “tuning” of flickering dipoles in the dispersion interaction process of the surfaces of supramolecular structures. To verify this assumption, the intrinsic thermal radio emission in the gigahertz range of the following nanoparticles was studied: virus-like particles (VLP) of SARS-CoV-2 and rotavirus A, monoclonal antibodies to various RBD epitopes of SARS-CoV-2, interferon-α, antibodies to interferon-γ, humic–fulvic acids, and silver proteinate. At 37 °C or when activated by light with λ = 412 nm, these particles all demonstrated an increased (by two orders of magnitude compared to the background) level of electromagnetic radiation in the microwave range. The thermal radio emission flux density specifically depended on the type of nanoparticles, their concentration, and the method of their activation. The thermal radio emission flux density was capable of reaching 20 μW/(m2 sr). The thermal radio emission significantly exceeded the background only for nanoparticles with a complex surface shape (nonconvex polyhedra), while the thermal radio emission from spherical nanoparticles (latex spheres, serum albumin, and micelles) did not differ from the background. The spectral range of the emission apparently exceeded the frequencies of the Ka band (above 30 GHz). It was assumed that the complex shape of the nanoparticles contributed to the formation of temporary dipoles which, at a distance of up to 100 nm and due to the formation of an ultrahigh strength field, led to the formation of plasma-like surface regions that acted as emitters in the millimeter range. Such a mechanism makes it possible to explain many phenomena of the biological activity of nanoparticles, including the antibacterial properties of surfaces.

Controlling the Quality of Nanodrugs According to Their New Property—Radiothermal Emission

“…The production and purification of recombinant VLPs consisting of four structural proteins, S, M, N, and E, of the SARS-CoV-2 virus, synthesized in the baculovirus expression system, are described in [ 1 ].…”

“…This Special Issue was conceived by the editors to publish fundamental and practical results on the study of the characteristics of drugs based on NPs: this is the subject of a kind of editorial article [ 1 ]. The idea of the Guest Editors was to reveal a fundamental property of biologically active NPs.…”

“…In contrast to the classical multi-point Coulomb interaction of a ligand with a receptor [ 2 , 3 , 4 ], the binding of a NP to a receptor involves a significant contribution from the Deryagin interaction—the mutual adjustment of flickering dipoles during the electromagnetic radiation of sticking surfaces [ 5 , 6 ]. As it turns out, if a biologically active NP has a non-spherical shape (non-convex polyhedron), then the formation of an unstable dipole with electron plasma-like inhomogeneity is possible [ 1 ]. In this case, the NP acts as a kind of “nano antenna-emitter”, the function of which, when a “nano antenna-receiver” appears, is to adjust the frequency and localization of the flickering dipoles to the energetically optimal adhesion of the surfaces [ 1 , 7 , 8 ].…”

“…As it turns out, if a biologically active NP has a non-spherical shape (non-convex polyhedron), then the formation of an unstable dipole with electron plasma-like inhomogeneity is possible [ 1 ]. In this case, the NP acts as a kind of “nano antenna-emitter”, the function of which, when a “nano antenna-receiver” appears, is to adjust the frequency and localization of the flickering dipoles to the energetically optimal adhesion of the surfaces [ 1 , 7 , 8 ]. In the general case, the radiation of a nanoantenna should be isotropic or with weakly expressed anisotropy [ 9 , 10 ].…”

“…In VLP, there are conformational viral epitopes that cause a strong T- and B-cell immune response [ 14 ]. The radiuses of VLPs range from 20 to 200 nm [ 1 , 15 ], which provides the best efficiency for penetration into the body’s lymphoid system. Recent experience in the development of VLP SARS-CoV-2 and rotavirus VLPs has demonstrated their high immunogenicity and their absence of side effects [ 16 , 17 , 18 ].…”