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Coronavirus disease 2019 is a serious disease that causes acute respiratory syndrome and negatively affects the central nervous system. SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) crosses the blood-brain barrier due to the S protein on the surface of the viral particles. Thus, it is important to develop compounds that not only have an inhibitory effect but are also capable of completely deactivating the S-protein function. This study describes the purposeful modification of porphyrins and proposes compounds, asymmetrically hetaryl-substituted porphyrins with benzothiazole, benzoxazole, and N-methylbenzimidazole residues, to deactivate the S-protein functions. Molecular docking of SARS-CoV-2 proteins with hetaryl-substituted porphyrins showed that the viral proteins S-, N-, and nsp13 exhibited the highest binding affinity. Hetaryl-substituted porphyrins form strong complexes (13–14 kcal/mol) with the receptor-binding domain of the S protein, while the distance from the porphyrins to the receptor-binding motif (RBM) does not exceed 20 Å; therefore, RBM can be oxidized by 1O2, which is generated by porphyrin. Hetaryl-substituted porphyrins interact with the nucleocapsid protein in the serine/arginine-rich region, and a number of vulnerable amino acid residues are located in the photooxidation zone. This damage complicates the packaging of viral RNA into new virions. High-energy binding of hetaryl-substituted porphyrins with the N- and C-terminal domains of nsp13 was observed. This binding blocks the action of nsp13 as an enzyme of exoribonuclease and methyltransferase, thereby preventing RNA replication and processing. A procedure for the synthesis of hetaryl-substituted porphyrins was developed, new compounds were obtained, their structures were identified, and their photocatalytic properties were studied., Graphical abstract Image 1

The chemical precipitation was used to obtain carbon fibers (CF) with surface modified by magnetite particles (Fe3O4). Processing was carried out by employing up to three subsequent coating stages ...

The effect of the content of silicon carbide whiskers and the sintering temperature on the physicomechanical and thermophysical properties of samples of a ceramic composite material (CCM) of the SiC–SiCw–B4C–AlN system with weight content of silicon carbide whiskers (SiCw) 10, 30, and 50%, obtained by spark plasma sintering. Introducing silicon carbide whiskers SiCw into CCM of the SiC–B4C–AlN system increased the bending strength and crack resistance, and at SiCw weight content 30 and 50% the strength and crack resistance of the CCM were at the same level.

Coatings based on the system Y2O3–Al2O3–SiO2 are promising for protecting silicon carbide based materials from the effects of an oxidizing atmosphere, water vapor, and salt vapors. The interaction of Y2O3–Al2O3–SiO2 coatings, obtained by the sol-gel method, with water vapor and Na2SO4 salt was investigated. Coatings based on the yttrium aluminosilicate system were found to have good oxidative and chemical resistance to water vapor and Na2SO4 salt at temperatures 1300 – 1450°C. The weight gain for the coated samples tested in Na2SO4 salt vapor did not exceed 1%. The initial SiC substrates are characterized by active oxidation processes with weight reduction from 8 to 11%.

—The effect of isovalent doping Sc3+ → In3+ on the transport properties is studied for complex oxide BaLaInO4 characterized by the Ruddlesden–Popper structure. It is shown that the introduction of scandium increases the oxygen-ionic and protonic conductivity. In the humid air atmosphere at 500°С, both BaLaInO4 and BaLaIn0.9Sc0.1O4 are the protonic conductors with ~90–95% contribution of proton transfer.

Due to the fact that cardiovascular diseases (CVD) are the leading cause of death worldwide, reducing risk factors and maintaining a healthy lifestyle play an important role in primary and secondary prevention of CVD development and improving prognosis. The purpose of the study. To study the eff ectiveness of carbon dioxide baths and water training in the primary prevention program for people with CVD risk factors. Material and methods. 60 patients (43 women and 17 men) with CVD risk factors were examined before and after a course of carbon dioxide baths and aquatic therapy. The hardware and software complex «Physiocontrol-R» was used. It includes, in addition to psychological testing (Spielberger, SAN, Lüscher tests, сardiointervalography (CIG) for the study of the autonomic regulation of the cardiovascular system, the study of the state of central and peripheral hemodynamics, Bioelectrical impedance analysis (BIA) for the study of body composition. Results. In the group of patients who took a complex of carbon dioxide baths and water training, in contrast to the control group, there was an improvement in the clinical condition, hemodynamic parameters, normalization of sympathicovagal balance and body composition. Conclusion. The aquatic therapy program in the pool and the use of HCV led to an improvement in the patients ‘ psychoemotional state, improvement of central and peripheral hemodynamics, and sympathico-vagal balance, which is associated with a reduced risk of developing CVD.

The effect of small doping additions (ten metal cations) on the structural characteristics of the sol-gel-synthesized silicas was evaluated by the SAXS method. Doping with cobalt, cerium, and silver cations led to separation of metal compounds as single phases. All the tested cations affected the radius of gyration and the fractal dimension of the resultant silicas.

Due to the emergence of a new coronavirus infection COVID-19, scientists around the world are actively working on a vaccine against the SARS-CoV-2 coronavirus. At the same time, it is possible that existing medications can help in the fight against this disease. The local antiseptic drug benzidamine hydrochloride in the early stages of illness can prevent the virus from entering the lower respiratory tract and potentially reduce the severe illness associated with pneumonia and, as a result, reduce COVID19-related hospitalizations, which can significantly reduce the burden on the health care system.The aim: to evaluate the antiviral activity of benzidamine hydrochloride against SARS-CoV-2 in vitro.Material and methods. Antiviral properties of benzidamine hydrochloride were studied in vitro in non-toxic concentrations on monolayer of Vero-E6 cells infected with pandemic strain of SARS-CoV-2 coronavirus in treatment and prophylactic scheme of the compound and virus administration.Results. Benzidamine hydrochloride has antiviral activity (15,0 mcg/ml), the efficiency of its antiviral action is directly proportional to the concentration of the substance.Conclusions. Taking into account very limited range of antiviral drugs with direct action on SARS-CoV-2 virus, the studied preparation can be used in complex therapy at early stages of the disease, which can prevent virus penetration into lower respiratory tract and potentially reduce the number of complications.

This paper presents the experimental results of rare earth element and yttrium (REY) biosorption in natural surface waters and groundwater in the presence of different concentrations of living and inactivated organotrophic bacteria (Curtobacterium sp., Ralstonia sp., Pseudomonas sp., Bacillus sp., Brevibacterium sp., Microbacterium sp.,) under different environmental pH conditions. We found that the biosorption process is mainly regulated by two factors: the pH of the aqueous solution and the species of bacteria. The acidity significantly affected the sorption capacity of bacteria for all of the studied strains. We found a decrease in REY sorption with an increase in pH due to lower absorption of REY on the cell walls of bacteria. The process of REY biosorption was more intensive in the living bacteria than inactivated microorganisms. At neutral pH values, all studied bacterial strains more actively adsorbed light REYs (lanthanum, praseodymium, and neodymium), in more acidic solutions (pH 2), an increase in Kd values ​​for heavy REY (lutetium and europium) was observed. The effect of bacterial biomass concentration on REY biosorption was demonstrated. The REY sorption decreased with an increase in the concentration of the live and inactivated bacteria.

The purpose of this study was reconstruction of dominant paleo-environments on northern and southern slopes of Alborz Mountain based on the modern and old environmental evidences preserved in the soils. Totally 691 soil profiles in 14 separate segments (9 segments in northern slope and 5 segments in southern slope) with an area of 783,850 ha (251 pedons in northern slope with about 123,600 ha; 440 pedons in southern slope with about 660,350 ha) in Alborz Mountains were studied. Morphological, physical, chemical, mineralogical, micromorphological, and geochemical analyses of the studied sites carried out using standard methods and demonstrated significant differences between the soils of northern and southern slopes. Micromorphological data showed that the calcite coatings in northern slope pedons have formed before the clay coatings however, while the opposite conditionings for calcite and clay coatings in southern slope were observed. The geochemical analyses results were in agreement with the results obtained from micromorphological analyses and further confirmed the addition of aeolian materials into the studied pedons in southern slope. Biological features and the organic and inorganic residues were extremely different in the northern and southern slopes. The maximum and minimum mean residence times (MRTs) in the subsurface layers were 4467 ± 50 years in deciduous forest and 4410 ± 48 years in coniferous forest in northern slope. However, the MRTs for burnt woods from the depths of 1.6 and 2.68 m of soil in southern slope were 3665 ± 61 and 6083 ± 84 years, respectively. Soils as archives of ecosystems contain very informative data for paleo-environmental and paleogeographic reconstructions. The results of this study demonstrated that the southern slope has been heavily influenced by glacial and aeolian deposits that in some cases have led to the top-down reverse distribution of the element oxides in the soil.

Novel porphyrin compounds containing benzothiazole, benzoxazole, and benzimidazole moieties have been prepared and their structures have been confirmed. Molecular docking of non-symmetric hetaryl-substituted porphyrins and chlorin e6 with SARS-CoV-2 helicase has been carried out. The affinity of hetaryl-substituted porphyrins to this protein has been found significantly higher than that of the drugs approved by the FDA and chlorin e6. The structure of the complexes of SARS-CoV-2 helicase with the considered macroheterocyclic compounds has been analyzed. Possible ways to inhibit and photoinactivate SARS-CoV helicase have been suggested basing on the localization of porphyrins and chlorin e6 in the helicase domains.

Abstract— The possible nitrogen sources for Osc. trichoides DG6, a typical strain of the Oscillochloridaceae family, are ammonium, N2, glutamate, asparagine, glycine, and glutamine. The assimilation of molecular nitrogen occurs with the participation of nitrogenase, the structural gene of which, nifH, is located in the gene cluster which also includes the genes of the nifD and nifK nitrogenase subunits and the auxiliary nifB gene. Considering that nifHBDK clusters have been also annotated in the genomes of other members of the Oscillochloridaceae family, including uncultured and candidate taxa, it can be assumed that the ability to fix nitrogen is a property immanent for this entire family. The pathways for assimilating ammonium in the cells grown using different nitrogen sources may differ. Osc. trichoides DG6 growing in a medium containing ammonium assimilated it with the participation of glutamate dehydrogenase, which is determined by a single gene. The expression product of this gene has dual functionality and can be used to implement the reaction with both NAD and NADP. With the growth of Osc. trichoides DG6 on a medium with glutamate as the only nitrogen source all the enzymes necessary for the implementation of the GS‑GOGAT pathway were found in the cells. However, for the glutamine synthetase reaction, ammonium, which was absent in the growth medium, was required. The source of ammonium may be glutamate metabolized through glutamate dehydrogenase.

We have studied structural and phase transformations of precursors to high-temperature coatings based on yttrium silicate and yttrium aluminosilicate systems and identified general trends in the influence of an oxidizing atmosphere on the heat resistance of coatings produced by slip casting/firing and atmospheric plasma spraying on silicon carbide composite materials at temperatures of up to 1500°C.

Composites of polycaprolactone with cellulose nanocrystals were produced, and their morphological, thermal, and strength characteristics were examined. It was found that nanocrystalline cellulose as a filler increased the porosity of the resultant composite materials. A conclusion was made that nanocrystalline cellulose can act as an initiator of polycaprolactone crystallization and affect the growth of the polymer crystallites. Incorporation of cellulose nanocrystals into the polycaprolactone matrix increased the hydrophilicity of the material and promoted an increase in water sorption while making the composite more brittle as indicated by decrease in the elongation at break and icreases in the tensile strength and Young’s modulus.

Acid–base membranes have been prepared by mixing a 1-vinyl-1,2,4-triazole polymer (PVT) with phenol-2,4-disulfonic acid (PDSA) in the presence of products of intermolecular crosslinking of polyvinyl alcohol and oxalic acid. The composition and structure of the membranes have been studied by elemental analysis and IR and NMR spectroscopy techniques. The membranes are thermally stable up to 245°C. Their electrical conductivity increases from 6.23 mS cm−1 (PVT–PDSA 80 : 20 wt % membrane) to 59.8 mS cm−1 (PVT–PDSA 10 : 90 wt %) with increasing temperature and phenol-2,4-disulfonic acid content at a temperature of 80°C and a humidity of 75%. The activation energy of the membranes ranges from 19.5 to 38.2 kJ/mol, respectively. The water uptake of membranes, which determines, among other things, the electrical conductivity, depends on the PVT content: the water uptake decreases from 200 to 50% with an increase in its amount in the membrane composition from 9.1 to 81.30 mol %, leading to a decrease in electrical conductivity along with a decrease in the proportion of PDSA.

A new composite adsorbent was obtained by hydrolytic polycondensation of N,N'-bis (3-triethoxysilyl propyl) thiocarbamide in the presence of poly-2-methyl-5-vinylpyridine. The sorption activity of the composite toward platinum (IV) ions was studied in hydrochloric acid solutions. The maximum extraction efficiency of Pt (IV) and the maximum values of sorptive capacity (218 mg g–1), and a coefficient of interphase distribution (7090 cm3 g–1) of the studied adsorbent in 1 М solution of HCl were found at 338 K. The Langmuir, Freundlich, and Dubinin–Radushkevich models were used to describe adsorption nature.

Abstract Soil organic matter (SOM) includes many classes of labile compounds available for microbial decomposition or, conversely, stable compounds protected from biodegradation by biological, chemical, and physical stabilization. It is believed that the more thermal energy is spent on the destruction of soil organic matter, the more stable and more resistant for biodegradation it is. We compared the thermal and biological stabilities of organic matter in eleven soil types from deciduous forest, forest-steppe, steppe, and semidesert bioclimatic areas of the European Russia. According to the activation energy (Ea), the highest SOM thermal stability was typical of the ordinary chernozem and meadow vertic soil. The lowest SOM thermal stability was found for gray forest soil; other soil types were characterized by an intermediate resistance towards thermal oxidation. The thermally labile pool (390–400°C) was on the average 59% (40–68%). The SOM biological stability estimated by the ratio of potentially mineralizable organic matter to that resistant to mineralization (biological stability index) decreased in the following order: ordinary chernozem (Haplic Chernozem (Loamic, Pachic)) > meadow vertic soil (Pellic Vertisol (Gleyic, Humic)) > gray forest soil (Luvic Greyzemic Phaeozem (Loamic)) = meadow chestnut soil (Gleyic Kastanozem (Chromic)) > meadow solonetz (Endosalic Gleyic Solonetz (Loamic, Cutanic)) > alluvial meadow soil (Eutric Fluvisol (Humic, Oxyaquic)). The potentially mineralizable SOM pool in the studied soils was 6–27-fold lower as compared with the pool of thermally labile SOM, and the parameters that characterize SOM thermal stability did not correlate with the biological stability index. Thus, SOM thermal lability is not identical to its biodegradability.

The article presents an overview of current issues of international regulation of the content of heavy metals (lead, cadmium, mercury and arsenic) in food. Special attention is paid to the revision of the standards for the content of arsenic in rice, mercury in some types of fish, cadmium in chocolate, lead in meat, offal, and wine. A comparative analysis of the standards -permissible levels of content of heavy metals in food products in the EU and the Russian Federation is carried out.

Quality control of recombinant interferon (rIFN) products with the help of modern analytical methods, including those used for identification, is becoming increasingly relevant nowadays. Identification is especially challenging in the case of Russian rIFN products that contain not only interferon (IFN) alpha-2b, but also other active ingredients and excipients that hinder the use of physical and chemical methods. Manufacturers of such products use IFN neutralization assay with mono- and/or polyclonal antibodies for identification. The aim of the study was to assess the feasibility of using different types of antibodies in the identification test based on neutralization of IFN antiviral activity in IFN alpha-2b products containing other active ingredients and excipients in addition to IFN. Materials and methods: the following materials were used in the study: MDBK cells, vesicular stomatitis virus, samples of IFN alpha-2b products with different composition and by different manufacturers, mono- and polyclonal antibodies by different manufacturers. Identification of rINFs was carried out by a biological method based on neutralization by specific antibodies of IFN ability to suppress the cytopathic effect of the indicator virus in a cell culture using a reference standard for comparison. Results: both polyclonal and monoclonal antibodies were shown to neutralize the activity of the tested IFN alpha-2b substances. Polyclonal antibodies interact with all products containing the same active ingredients, irrespective of their composition. Monoclonal antibodies interact selectively with some products. Conclusions: polyclonal antibodies can be used for identification of any product containing IFN alpha-2b. The use of monoclonal antibodies for this purpose is limited and depends on the composition of the product.

The object of this study was layered double hydroxides (LDH) with a cationic composition M2+3Al1-xCexwhere the doubly charged cation is nickel or cobalt. For comparison, we used samples of a similar cationic composition that does not contain cerium. Synthesis by coprecipitation followed by hydrothermal treatment allowed obtaining single-phase well-crystallized LDH with a hydrotalcite structure, as was evidenced by the data from an X-ray phase analysis. The main goal of this study was the investigation of the effect of the introduction of a large cerium cation into the structure of brucite-like layers of LDH on the sorption characteristics of these materials. As was shown using low-temperature adsorption-thermal desorption of nitrogen according to BET the method, the cationic composition of LDH had a significant effect on the specific surface area of the synthesized materials. Nickel-containing LDH have a more developed surface than cobalt-containing ones. The nitrogen adsorption-thermal desorption isotherms are of type II according to the classification of BDDT and are characteristic of non-porous or macroporous bodies. The sorption capacity of LDH in relation to the Congo red anionic dye was determined by the static method. The concentration of dyes in solutions was determined spectrophotometrically. Experimental data of kinetic studies of dye sorption on LDH were analysed using pseudo-first (Laguerin's model) and pseudo-second (Ho and McKay's model) orders. It was found that the sorption of the dye on all synthesized LDH samples was adequately described by the pseudo-second order model. Experimental data on the equilibrium adsorption of the dye on LDH were analysed using the widely used Freundlich and Langmuir isotherm models. It was shown that sorption isotherms for all samples can be attributed to type L and in the studied concentration range they are satisfactorily described by the Langmuir model. An inflection was observed on the sorption isotherms, the presence of which may be due to the reorientation of the adsorbed particles relative to the sorbent surface or a change in the sorption mechanism from surface to intercalation mechanism. It was found that the introduction of a large cerium cation into the structure of brucite-like layers of LDH led to a significant increase in the sorption capacity of these materials with respect to the anionic dye, the maximum adsorption value calculated using the Langmuir equation was 1.4 - 2.3 times higher for cerium-containing LDH. The obtained results can be used in the sorption and catalytic studies of LDH.

Composite materials that contain tetracationic hydrotalcite-like layered double hydroxide and a cobalt-iron spinel phase were prepared by coprecipitation from a solution of a mixture of magnesium, aluminum, cobalt(II), and iron(III) salts followed by hydrothermal treatment. The iron and cobalt contents in the samples were varied within a broad range. The thermal transformations of the prepared composites were examined by high-temperature X-ray diffraction, and the layered hydroxide phase was found to remain when heated up to 300°C. The specific magnetization and magnetic susceptibility of the materials were determined using a vibrating sample magnetometer; a rise in the iron and cobalt contents was found to increase the magnetization up to a certain limit. The obtained samples can be used as magnetic sorbents. The sorption capacity of materials was estimated using Congo red anionic dye as an example.

High-voltage (2000V) 4H-SiC Schottky diodes are fabricated. To suppress the premature breakdown at the edge of diode structures, a field plate is formed as the edge termination. In this plate, an insulator layer is formed via the self-aligned implantation of high-energy (53 MeV) argon ions into 4H-SiC. To mask the active region of the diodes, 10–12-μm-thick nickel columns with vertical walls are grown on Schottky contacts by local electrochemical deposition. A comparison of the current–voltage characteristics of terminated and nonterminated diodes shows that the forward current–voltage characteristics barely degrade after implantation, whereas the reverse current–voltage characteristics are greatly improved. Both the forward and reverse current–voltage characteristics of terminated diodes are well described in terms of the classical thermionic emission model if lowering of the Schottky-barrier height with increasing bending of energy bands is taken into account.

It is an urgent task today to seek and implement nature-like technologies in broiler production and obtain biologically complete and safe poultry products, thus refusing from antibiotic use in feed. Feed additives based on natural components can be an effective tool for implementation of preventive and therapeutic veterinary measures. The paper presents research study results of application of betulin-based phytobiotics in broiler farming. The tests were carried out on Ross-308 cross-breed broiler chickens within the production cycle at one of the poultry farms of the Sverdlovsk Oblast. Birds of the experimental group received compound feed supplemented with dry betulin at 2.5 mg/kg of live weight from day 21 to day 35 of growing. The introduction of betulin-based feed additive into the diet contributed to increase in live weight gain and 7.6% pectoralis muscle output as compared with the control group. It was established that the phytobiotic consumption resulted in reduced deposition of subcutaneous and abdominal fat, higher biological value of meat by increasing the ash content, improved technological properties of meat due to increasing water-holding capacity of muscle fiber and intensity of formation and maturation of muscle fiber. Histological studies of pancreatic tissue samples from broiler chickens showed increase in the mass of islets of Langerhans and insulin-producing cell complexes. The pancreas was activated due to effects of the betulin-based feed additive. The results obtained indicate that the use of betulin in broiler production is a promising trend.

The effect of inoculation with endotrophic micromycete Cylindrocarpon magnusianum on the physiological and biochemical parameters of test tomato plants when exposed to heavy metal salts was studied. The experimental scheme included inoculation with a fungal culture (control population) and with populations of this fungus that were previously adapted to this stress factor. The inoculated plants were then grown under control conditions and on substrates with different concentrations of heavy metal salts (zinc, copper, lead, and chromium). No stimulating effect that increases the resistance of plants to heavy metal salts after inoculation of plants by the control population of the fungus C. magnusianum was detected. When using nonbiogenic chemical elements, adaptive plant responses associated with the content of photosynthetic pigments in leaves and the formation of plant biomass were significantly expressed when plants were inoculated with adapted fungal populations of C. magnusianum and when they were further cultivated on substrates introduced with chromium and lead salts. Under these conditions, the fungal infection in plant roots was more intense compared to the use of the control population of the fungus. These facts indicate the more efficient partnership of the fungus C. magnusianum and the root system of plants under conditions that are extreme for plant life.

The rheological properties of dilute and moderately concentrated solutions of methyl cellulose–chitosan blends in aqueous solutions of acetic and succinic acids are studied. Using dynamic mechanical, thermogravimetric, and X-ray diffraction analyses, the structural organization of composite films is investigated, the temperatures of relaxation transitions are determined, and the composition regions in which the polymers are miscible and form mixed structures are estimated.

Modern process methods and approaches to production of useful electrode materials make it possible to design alternative power sources, in particular, fuel cells with high specific characteristics. Owing to their unique properties, carbon nanotubes and porous silicon are the most promising materials for developing micropower current sources. Substrates based on porous silicon have high corrosion and mechanical resistance, and they also feature a large pore surface area. Hence, the search for the best composition of matrix carriers with a large active surface and modifier metals with their minimum load is becoming an urgent process problem in power and electronic engineering. The use of metal nanoparticles in a catalyst can increase the catalytic activity in electrochemical reactions occurring in fuel cells and their corrosion resistance. Investigations into electrochemical oxidation of hydrogen and formic acid in fuel cells seem to be the most important for practice due to a wide application range of these types of fuels. This work deals with the formation of nanocomposite electrodes with nanoparticles of platinum group metals for fuel cells to be used as self-contained micropower current sources in electronic engineering. A process is described for forming effective electrode materials based on nanotubes with nanoparticles of platinum (Pt) and palladium (Pd) for low-temperature self-contained power sources. Parameters of nanocomposite electrodes in matrix-carriers are investigated by the methods of atomic-force, high-resolution transmission electron microscopy. The results from tests of formic acid–air and hydrogen–air fuel cell models are presented. The optimal loading of platinum group metals and dimensions of electrode nanocomposites giving maximum specific power and current density are found.

The cyclic voltammetry method was used for studying the electrochemical oxidation of benzene, diphenyl and p-terphenyl in ionic liquid N-butylpyridinium chloride–AlCl3 (1 : 1.5) at 30°C. Comparative analysis of peaks obtained for each initial monomer was performed. The assumptions on the differences in the mechanisms of electrochemical synthesis of polyphenylenes in the ionic liquid from benzene, diphenyl and p-terphenyl were made.

A self-consistent field theory is applied to study structural properties of micelles formed upon spontaneous assembly of diblock copolymers comprising soluble dendron block covalently linked to insoluble linear block in selective solvent. The structure of spherical micelles is analyzed as a function of degrees of polymerization of the blocks and number of generations and branching functionality of the dendron block. We demonstrate that for a given molecular mass of blocks both the hydrodynamic dimensions of the micelles and the aggregation number decrease as a function of the degree of branching of the dendron block. However, the number of potentially functionalizable terminal segments of dendrons in the corona exposed to the solution increases compared to the number of terminal groups in the corona of linear diblock copolymer micelle. This result may have important implications for construction of linear–dendritic block copolymer micelles with smart functionalities for targeted drug and gene delivery.

Bottlebrush macromolecules can be regarded as molecular tensile machines, where tension is self-generated along the backbone due to steric repulsion between densely grafted side chains. This intrinsic tension is amplified upon adsorption of bottlebrush molecules onto a substrate and increases with grafting density, side chain length, and strength of adhesion to the substrate. To investigate the effects of tension on the electronic structure of polythiophene (PT), bottlebrush macromolecules were prepared by grafting poly(n-butyl acrylate) (PBA) side chains from PT macroinitiators by atom transfer radical polymerization (ATRP). The fluorescence spectra of submonolayers of PT bottlebrushes were measured on a Langmuir–Blodgett (LB) trough with the backbone tension adjusted by controlling the side-chain length, surface pressure, and chemical composition of a substrate. The wavelength of maximum emission has initially red-shifted, followed by a blue-shift as the backbone tension increases from 0 to 2.5 nN, whic...