The complexation of biogenic molecules with metals is the widespread strategy in screening for new pharmaceuticals with improved therapeutic and physicochemical properties. This paper demonstrates the possibility of using simple QSAR modeling based on topological descriptors for chelates study. The presence of a relationship between the structure (J) and lipophilic properties (logP) of zinc complexes with amino acids, where two molecules coordinate the central atom through carboxyl oxygen and amino group nitrogen, and thus form a double ring structure, was predicted. Using a cellular biosensor model for Gly, Ala, Met, Val, Phe and their complexes Zn(AA)₂, we experimentally confirmed the existence of a direct relationship between logP and biological activity (Ea). The results obtained using topological analysis, Spirotox method and microbiological testing allowed us to assume and prove that the chelate complex of zinc with methionine has the highest activity of inhibiting bacterial biofilms, while in aqueous solutions it does not reveal direct antibacterial effect.

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.

In the present work, the methods of dynamic light scattering and fluorescence spectroscopy were applied to study the optical properties of aqueous dilutions of the humic substances complex (HC) as a potential drug delivery system. The supramolecular structures in the humate solution were characterized as monodisperse systems of the submicron range with a tendency to decrease in particle size with a decrease in the dry matter concentration. The slightly alkaline medium (8.3) of the studied aqueous dilutions of HC causes the absence of a pronounced fluorescence maximum in the region from 400 to 500 nm. However, the presence of an analytically significant, inversely proportional to the concentration second-order scattering (SOS) signal at 2λ_ex = λ_em was shown. In the examples of the antiviral substances mangiferin and favipiravir, it was shown that the use of the humic complex as a drug carrier makes it possible to increase the solubility by several times and simultaneously obtain a system with a smaller particle size of the dispersed phase. It has been shown that HC can interact with mangiferin and favipiravir to form stable structures, which lead to a significant decrease in SOS intensities on HC SOS spectra. The scattering wavelengths, λ_ex/λ_em, were registered at 350 nm/750 nm for mangiferin and 365 nm/730 nm for favipiravir, respectively. The increments of the scattering intensities (I0/I) turned out to be proportional to the concentration of antiviral components in a certain range of concentrations.

Natural polyelectrolytes, including in the form of complexes with colloidal particles, are increasingly used in pharmacy due to the possibility of regulated attachment of medicinal substances and their targeted delivery to the target organ. However, the formation, stability, and molecular-mass characteristics of polyelectrolyte nanodispersions (ND) vary depending on the nature and composition of the medium of their origin. This is due to the lack of standardized approaches to quality control and regulatory documentation for most natural ND. In this paper, we first introduced the isolation, followed by investigations into their physico-chemical properties and bioactivity. Using the dried droplet method, we were able to detect the “coffee ring effect”. Fractographic studies of the surface structure of EHA and FA dried samples using SEM showed its heterogeneity and the presence of submicron particles encapsulated in the internal molecular cavities of polyelectrolyte. FTIR spectroscopy revealed the ND chemical structure of benzo-α-pyron and benzo-γ-pyron, consisting of nanoparticles and a branched frame part. The main elements detected by X-ray fluorescence in humic substance extract and fulvic acid include Si, P, S, K, Ca, Mn, Fe, Cu, Zn, whereas Fe is in high concentrations. The UV-spectra and fluorescent radiation demonstrated the possibility of studying the effect of the fulvate chromone structure on its optical properties. It is shown that dilution of the initial solutions of polyelectrolytes 1:10 contributes to the detection of smaller nanoparticles and an increase in the absolute value of the negative ζ-potential as a factor of ND stability. A study of the EHS effect on the SARS-CoV-2 virus infectious titer in the Vero E6 cell showed the effective against virus both in the virucidal scheme (the SI is 11.90–22.43) and treatment/prevention scheme (the SI is 34.85–57.33). We assume that polyelectrolyte ND prevent the binding of the coronavirus spike glycoprotein to the receptor. Taking into account the results obtained, we expect that the developed approach can become unified for the standardization of the ND natural polyelectrolytes complex, which has great prospects for use in pharmacy and medicine as a drug with antiviral activity.

Nanoparticles (NPs) represent a unique class of structures in the modern world. In comparison to macro- and microparticles, NPs exhibit advantages due to their physicochemical properties. This has resulted in their extensive application not only in technical and engineering sciences, but also in pharmacy and medicine. A recent analysis of the scientific literature revealed that the number of articles related to the search term “nanoparticle drugs” has exceeded 65,000 in the last decade alone, according to PubMed. The growth of scientific publications on NPs and nanomaterials (NMs) in pharmacy demonstrates the rapidly developing interest of scientists in exploring alternative ways to deliver drugs, thereby improving their pharmacokinetic and pharmacodynamic properties, and the increased biocompatibility of many nanopharmaceuticals is a unique key to two mandatory pharmaceutical requirements—drug efficacy and safety. A comprehensive review of the literature indicates that the modern pharmaceutical industry is increasingly employing nanostructures. The exploration of their physicochemical properties with a subsequent modern approach to quality control remains the main task of modern pharmaceutical chemistry. The primary objective of this review is to provide a comprehensive overview of data on NPs, their physicochemical properties, and modern approaches to their synthesis, modification of their surface, and application in pharmacy.

Previous studies have shown that complexly shaped nanoparticles (NPs) have their intrinsic radiothermal emission in the millimeter range. This article presents a method for controlling the quality of nanodrugs—immunobiological preparations (IBPs)—based on the detection of their intrinsic radiothermal emissions. The emissivity of interferon (IFN) medicals, determined without opening the primary package, is as follows (µW/m²): IFN-α2b—80 ± 9 (10⁵ IU per package), IFN-β1a—40 ± 5 (24 × 10⁶ IU per package), IFN-γ—30 ± 4 (10⁵ IU per package). The emissivity of virus-like particles (VLP), determined using vaccines Gam-VLP-multivac (120 μg) in an injection bottle (crimp cap vials), was as follows: 12 ± 1 µW/m², Gam-VLP—rota vaccines—9 ± 1 µW/m². This study shows the reproducibility of emissivity over the course of a year, subject to the storage conditions of the immunobiological products. It has been shown that accelerated aging and a longer shelf life are accompanied by the coagulation of active NPs, and lead to a manyfold drop in emissivity. The dependence of radiothermal emission on temperature has a complex, non-monotonic nature. The emission intensity depends on the form of dosage, but remains within the order of magnitude for IFN-α2b for intranasal aqueous solution, ointments, and suppositories. The possibility of the remote quantitative control of the first phases of the immune response (increased synthesis of IFNs) to the intranasal administration of VLP vaccines has been demonstrated in experimental animals.