Application of carbon nanostructures in biomedicine: realities, difficulties, prospects.

The review systematizes data on the wide possibilities of practical application of carbon nanostructures. Much attention is paid to the use of carbon nanomaterials in medicine for the visualization of tumors during surgical interventions, in the creation of cosmetics, as well as in agriculture in the creation of fertilizers. Additionally, we demonstrate trends in research in the field of carbon nanomaterials with a view to elaborating targeted drug delivery systems. We also show the creation of nanosized medicinal substances and diagnostic systems, and the production of new biomaterials. A separate section is devoted to the difficulties in studying carbon nanomaterials. The review is intended for a wide range of readers, as well as for experts in the field of nanotechnology and nanomedicine.

Recombinant Fusion Protein Containing Plant Nigellothionin Regulates the Growth of Food-Spoiling Fungus (Aspergillus niger).

This study aimed to obtain a recombinant chimeric protein named trx-NsW2 via theheterologous expression of the multifunctional antimicrobial peptide nigellothionin from black cumin (Nigella sativa L.) seeds in the Escherichia coli system. The protein was purified using a combination of Ni-NTA affinity chromatography and reversed-phase HPLC. Based on the HPLC calibration, the total yield of the protein was calculated to be 650 mg/L of bacterial culture. The fungistatic activity of trx-NsW2 against the food-spoiling fungus Aspergillus niger was demonstrated as itinhibited the maturation of conidiawithout affecting conidial germination or fungal growth. In contrast to mature nigellothionin NsW2, the fusion protein showeda low level of cytotoxicity towards both normal and tumor cell lines at concentrationsof up to 100-200 µM. Interestingly, at lower concentrations, it even stimulated cytokinesis. These findings are of critical importance for applying chimeric antimicrobial proteins obtained via microbiological synthesis in applied science.

C60 adduct with L-arginine as a promising nanomaterial for treating cerebral ischemic stroke.

The work aimed to investigate the biocompatibility and biological activity of the water-soluble fullerene adduct C60-Arg. It was found that the material is haemocompatible, is not cyto- and genotoxic, possesses pronounced antioxidant activity. Additionally, this paper outlines the direction of application of water-soluble fullerene adducts in the creation of neuroprotectors. It has been suggested that a putative mechanism of the protective action of the C60-Arg adduct is associated with its antioxidant properties, the ability to penetrate the blood-brain barrier, and release nitrogen monoxide as a result of the catabolism of L-arginine residues, which promote vascular relaxation. The action of the C60-Arg adduct was compared with the action of such an antioxidant as Edaravone, which is approved in Japan for the treatment of ischemic and haemorrhagic strokes.

Development of Fluorescent Isocoumarin-Fused Oxacyclononyne - 1,2,3-Triazole Pairs.

Fluorescent isocoumarin-fused cycloalkynes, which are reactive in SPAAC and give fluorescent triazoles regardless of the azide nature, have been developed. The key structural feature that converts the non-fluorescent cycloalkyne/triazole pair to its fluorescent counterpart is the pi-acceptor group (COOMe, CN) at the C6 position of the isocoumarin ring. The design of the fluorescent cycloalkyne/triazole pairs is based on the theoretical study of the S1 state deactivation mechanism of the non-fluorescent isocoumarin-fused cycloalkyne IC9O using multi-configurational ab initio and DFT methodologies. The calculations revealed that deactivation proceeds through the electrocyclic ring opening of the α-pyrone cycle and is accompanied by a redistribution of electron density in the fused benzene ring. We proposed that the S1 excited state deactivation barrier could be increased by introducing a pi-acceptor group into a position that is in direct conjugation with the formed C=O group and has a reduced electron density in the transition state. As a proof of concept, we designed and synthesized two fluorescent isocoumarin-fused cycloalkynes IC9O-COOMe and IC9O-CN bearing pi-acceptors at the C6 position. The importance of the nature of a pi-acceptor group was shown by the example of much less fluorescent CF3 -substituted cycloalkyne IC9O-CF3 .

Covalent conjugates based on nanodiamonds with doxorubicin and a cytostatic drug from the group of 1,3,5-triazines: Synthesis, biocompatibility and biological activity.

We report the synthesis of covalent conjugates of nanodiamonds with doxorubicin and a cytostatic drug from the class of 1,3,5-triazines. The obtained conjugates were identified using a number of physicochemical methods (IR-spectroscopy, NMR-spectroscopy, XRD, XPS, TEM). As a result of our study, it was found that ND-СONH-Dox and ND-COO-Diox showed good hemocompatibility, since they did not affect plasma coagulation hemostasis, platelet functional activity, and erythrocyte membrane. The ND-COO-Diox conjugates are also capable of binding to human serum albumin due to the presence of ND in their composition. In the study of the cytotoxic properties of ND-СONH-Dox and ND-COO-Diox in the T98G glioblastoma cell line, indicating that ND-СONH-Dox and ND-COO-Diox demonstrate greater cytotoxicity at lower concentrations of Dox and Diox in the composition of the conjugates compared to individual drugs; the cytotoxic effect of ND-COO-Diox was statistically significantly higher than that of ND-СONH-Dox at all concentrations studied. Greater cytotoxicity at lower concentrations of Dox and Diox in the composition of conjugates compared to individual cytostatics makes it promising to further study the specific antitumor activity and acute toxicity of these conjugates in models of glioblastoma in vivo. Our results demonstrated that ND-СONH-Dox and ND-COO-Diox enter HeLa cells predominantly via a nonspecific actin-dependent mechanism, while for ND-СONH-Dox a clathrin-dependent endocytosis pathway. All data obtained provide that the synthesized nanomaterials show a potential application as the agents for intertumoral administration.

Pathogenetic role and clinical significance of interleukin-1ß in cancer.

In recent years, pro-oncogenic mechanisms of the tumour microenvironment (ТМЕ) have been actively discussed. One of the main cytokines of the TМЕ is interleukin-1 beta (IL-1ß), which exhibits proinflammatory properties. Some studies have shown an association between an increase in IL-1ß levels and tumour progression. The purpose of this review is to analyse the pathogenic mechanisms induced by IL-1ß in the TМЕ, as well as the diagnostic significance of the presence of IL-1ß in patients with cancer and the efficacy of treatment with IL-1ß inhibitors. According to the literature, IL-1ß can induce an increase in tumour angiogenesis due to its effects on the differentiation of epithelial cells, pro-angiogenic molecule secretion and expression of adhesion molecules, thus increasing tumour growth and metastasis. IL-1ß is also involved in the suppression of anti-tumour immune responses. The expression and secretion of IL-1ß has been noted in various types of tumours. In some clinical studies, an elevated level of IL-1ß was found to be associated with low efficacy of anti-cancer therapy and a poor prognosis. In most experimental and clinical studies, the use of IL-1ß inhibitors contributed to a decrease in tumour mass and an increase in the response to anti-tumour drugs.

Biocompatibility and biological activity of C70 fullerene adduct with L-threonine (C70(C4H9NO3)2).

The aim of this work is to synthesise and study the biocompatibility and biological activity of the C70 fullerene adduct with l-threonine (C70-Thr). The obtained adduct was identified using a complex of physicochemical methods, namely, 13C NMR spectroscopy, IR spectroscopy, thermogravimetric analysis, electron spectroscopy, elemental analysis, and high-performance liquid chromatography. The study of biocompatibility and biological activity of the C70-Thr adduct included the study of haemocompatibility (haemolysis, platelet aggregation, plasma coagulation haemostasis, binding to human serum albumin, esterase activity), antiradical activity, cytotoxicity, cell proliferation, and interaction with DNA (determination of the DNA binding constant and genotoxicity).

Study of biocompatibility, cytotoxic activity in vitro of a tetrazole-containing derivative of 2-amino-4,6-di(aziridin-1-yl)-1,3,5-triazine.

The hydrolytic stability, hemocompatibility, antioxidant properties and in vitro cytotoxic activity of {5-[(4,6-di(aziridin-1-yl)-1,3,5-triazin-2-yl)amino]-2,2-dimethyl-1,3-dioxan-5-yl}methyl 2-(5-phenyl-2H-tetrazol-2-yl)acetate have been studied. 1H NMR spectroscopy showed that this tetrazole-containing derivative of 1,3,5-triazine is stable in neutral (pH 7) and alkaline (pH 10) media; hydrolysis of the dioxane cycle occurs in an acidic environment (pH 3). It has been established that {5-[(4,6-di(aziridin-1-yl)-1,3,5-triazin-2-yl)amino]-2,2-dimethyl-1,3-dioxan-5-yl}methyl-2-(5-phenyl-2H-tetrazol-2-yl)acetate is hemocompatible, exhibits antioxidant properties, but does not show antiradical activity over the entire range of concentrations. In turn, the study of cytotoxic activity in vitro showed that the tetrazole-containing derivative of 1,3,5-triazine has an effect on the cell lines of human alveolar basal epithelium adenocarcinoma A549 (IC50 41.3 µmol l-1), human ovarian teratocarcinoma PA-1 (IC50 10.6 µmol l-1), hepatocarcinoma Huh7 (IC50 19.9 µmol l-1), cervical cancer HeLa (IC50 3.7 µmol l-1), and human embryonic kidney HEK293 (IC50 15.8 µmol l-1). It was suggested one of the possible mechanism of substance 2 cytotoxicity via HIF pathway inhibition.

Biocompatibility, antioxidant activity and collagen photoprotection properties of C60 fullerene adduct with L-methionine.

Functionalization of the fullerene core with amino acids has become a new and promising direction in the field of nanochemistry. The biologic activity of water-soluble fullerene derivatives is based on such properties as lipophilicity, electron deficiency and photosensitivity. The complex of above-mentioned properties can be used to develop protection of biomolecules (in particular, proteins) from external physical and chemical influences. Thus, development and up-scaling of synthesis procedures, as well as investigation of the biological properties of these derivatives, are extremely important. This paper presents new data on the biocompatibility studies of C60 fullerene adduct with L-methionine (C60[C5H11NO2S]3; C60-Met). Antiradical activity, binding to human serum albumin (HSA), collagen and deoxyribonucleic acid (DNA), hemocompatibility, photodynamic properties, genotoxicity and cytotoxicity were studied. In addition, it was found that C60-Met increases the photostability of the collagen molecule, and this effect is dose-dependent.

Graphene oxide enriched with oxygen-containing groups: on the way to an increase of antioxidant activity and biocompatibility.

The article is dedicated to the comprehensive biocompatibility investigation of synthesised graphene oxide (GO) enriched with oxygen-containing functional groups (⁓85%). GO was synthesised through a modified Hummers and Offeman's method and characterised using 13C NMR, Raman, and IR spectroscopy, XRD, HRTEM, along with size dimensions and ζ-potentials in aqueous dispersions. Biocompatibility study included tests on haemocompatibility (haemolysis, platelet aggregation, binding to human serum albumin and its esterase activity), antioxidant activity (2,2-diphenyl-1-picrylhydrazyl reaction, NO-radical uptake, Radachlorin photobleaching, photo-induced haemolysis), genotoxicity using DNA comet assay, as well as metabolic activity and proliferation of HEK293 cells.

Graphene Oxide of Extra High Oxidation: A Wafer for Loading Guest Molecules.

We present a new modification of graphene oxide with very high content (85 wt %) of oxygen-containing functional groups (hydroxy, epoxy, lactol, carboxyl, and carbonyl groups) that forms stable aqueous dispersion in up to 9 g·L-1 concentration solutions. A novel faster method of the synthesis is described that produces up to 1 kg of the material and allows controlling the particle size in solution. The synthesized compound was characterized by various physicochemical methods and molecular dynamics modeling, revealing a unique structure in the form of a multilayered wafer of several sheets thick, where each sheet is highly corrugated. The ragged structure of the sheets forms pockets with hindered mobility of water that leads to the possibility of trapping guest molecules.

Heterocycloalkynes Fused to a Heterocyclic Core: Searching for an Island with Optimal Stability-Reactivity Balance.

In the search for fundamentally new, active, stable, and readily synthetically accessible cycloalkynes as strain-promoted azide-alkyne cycloaddition (SPAAC) reagents for bioorthogonal bioconjugation, we integrated two common approaches: the reagent destabilization by the increase of a ring strain and the transition state stabilization through electronic effects. As a result new SPAAC reagents, heterocyclononynes fused to a heterocyclic core, were created. These compounds can be obtained through a general synthetic route based on four crucial steps: the electrophile-promoted cyclization, Sonogashira coupling, Nicholas reaction, and final deprotection of Co-complexes of cycloalkynes from cobalt. Varying the natures of the heterocycle and heteroatom allows for reaching the optimal stability-reactivity balance for new strained systems. Computational and experimental studies revealed similar SPAAC reactivities for stable 9-membered isocoumarin- and benzothiophene-fused heterocycloalkynes and their unstable 8-membered homologues. We discovered that close reactivity is a result of the interplay of two electronic effects, which stabilize SPAAC transition states (πin* → σ* and π* → πin*) with structural effects such as conformational changes from eclipsed to staggered conformations in the cycloalkyne scaffold, that noticeably impact alkyne bending and reactivity. The concerted influence of a heterocycle and a heteroatom on the polarization of a triple bond in highly strained cycles along with a low HOMO-LUMO gap was assumed to be the reason for the unpredictable kinetic instability of all the cyclooctynes and the benzothiophene-fused oxacyclononyne. The applicability of stable isocoumarin-fused azacyclononyne IC9N-BDP-FL for in vitro bioconjugation was exemplified by labeling and visualization of HEK293 cells carrying azido-DNA and azido-glycans.

In Vitro and In Silico Investigation of Water-Soluble Fullerenol C60(OH)24: Bioactivity and Biocompatibility.

Light fullerenes, C60 and C70, have significant potential in biomedical applications due to their ability to absorb reactive oxygen species, inhibit the development of tumors, inactivate viruses and bacteria, and as the basis for developing systems for targeted drug delivery. However, the hydrophobicity of individual fullerenes complicates their practical use; therefore, creating water-soluble derivatives of fullerenes is increasingly important. Currently, the most studied soluble adducts of fullerenes are polyhydroxy fullerenes or fullerenols. Unfortunately, investigations of fullerenol biocompatibility are fragmental. They often lack reproducibility both in the synthesis of the compounds and their biological action. We here investigate the biocompatibility of a well-defined fullerenol C60(OH)24 obtained using methods that minimize the content of impurities and quantitatively characterize the product's composition. We carry out comprehensive biochemical and biophysical investigations of C60(OH)24 that include photodynamic properties, cyto- and genotoxicity, hemocompatibility (spontaneous and photo-induced hemolysis, platelet aggregation), and the thermodynamic characteristics of C60(OH)24 binding to human serum albumin and DNA. The performed studies show good biocompatibility of fullerenol C60(OH)24, which makes it a promising object for potential use in biomedicine.

Evaluation of the C60 biodistribution in mice in a micellar ExtraOx form and in an oil solution.

The article is devoted to the study of the pharmacokinetics of fullerene C60 in oil and micellar forms, analysis of its content in blood, liver, lungs, kidneys, heart, brain, adrenal glands, thymus, testicles, and spleen. The highest accumulation of C60 was found in the liver and adrenal glands. As a result of the studies carried out, it was shown that the bioavailability of C60 in the micellar form is higher than that in an oil solution.

Biocompatibility of a nanocomposite based on Aerosil 380 and carboxylated fullerene C60[C(COOH)2]3.

Silica is silicon dioxide, which, depending on the production method, can exist in various amorphous forms with varying specific surface area, particle size, pore volume and size, and, as a result, with different physicochemical and sorption characteristics. The presence of silanol groups on the surface of silicas provides the possibility of its further functionalisation. In addition, the developed specific surface of Aerosil allows to obtain composites with a high content of biologically active substances. In this work, we studied the biocompatibility of a composite based on Aerosil 380 and carboxylated fullerene C60[C(COOH)2]3, namely: haemolysis (spontaneous and photoinduced), platelet aggregation, binding to HSA, cyto- and genotoxicity, antiradical activity. Interest in the creation of this nanomaterial is due to the fact that carboxylated fullerenes have potential applications in various fields of biomedicine, including the ability to bind reactive oxygen species, inhibition of tumour development, inactivation of viruses and bacteria. The obtained composite can be used for the immobilisation of various drugs and the further development of drugs for theranostics.

Physicochemical properties, biological activity and biocompatibility of water-soluble C60-Hyp adduct.

Amino acid adducts of light fullerenes have a potential of application in a variety of fields of biomedicine, that is reactive oxygen species scavenging activity, anticancer activity, viruses and bacteria inactivation etc. In this work, the water-soluble C60 fullerene derivative with l-hydroxyproline (C60(C5H9NO3)2, C60-Hyp) was studied. Extensive biomedical investigation of this compound, namely, antiradical activity in the reaction with stable diphenylpicrylhydrazyl radical, the binding to human serum albumin, photodynamic properties, cytotoxicity in glioblastoma A172 and lung carcinoma A549 cell lines, erythrocytes haemolysis, platelet aggregation, genotoxicity on human peripheral blood mononuclear cells was conducted. Moreover, the dynamic and structural characteristics of C60-Hyp-H2O binary system were obtained using molecular dynamic (MD) method, and size distribution along with ζ-potentials of C60-Hyp associates was measured.

Reduction and functionalization of graphene oxide with L-cysteine: Synthesis, characterization and biocompatibility.

This article presents data on the synthesis, identification, computer simulation and biocompatibility of graphene oxide (GO) functionalized with L-cysteine (GFC). It was determined that GO reacts with L-cysteine in two different ways: in an alkaline medium, L-cysteine reduces functional groups on the surface and at the boundaries of GO; with heating and the use of thionyl chloride, L-cysteine covalently attaches to GO through carboxylic groups only at the boundaries. The identification of GO, reduced graphene oxide and GFC was performed using various physicochemical methods, including infrared spectroscopy, Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, thermogravimetric analysis, scanning electron microscopy and high-resolution transmission electron microscopy. Biocompatibility experiments included erythrocyte hemolysis, platelet aggregation, photodynamic and antiradical activity, binding to human serum albumin, and geno- and cytotoxicity studies. Applying density functional theory and molecular dynamics allowed us to obtain the structural and dynamic characteristics of a GFC-water binary system.

Arene-Ruthenium(II) Complexes Containing 11H-Indeno[1,2-b]quinoxalin-11-one Derivatives and Tryptanthrin-6-oxime: Synthesis, Characterization, Cytotoxicity, and Catalytic Transfer Hydrogenation of Aryl Ketones.

A series of novel mono- and binuclear arene-ruthenium(II) complexes [(p-cym)Ru(L)Cl] containing 11H-indeno[1,2-b]quinoxalin-11-one derivatives or tryptanthrin-6-oxime were synthesized and characterized by X-ray crystallography, IR, NMR spectroscopy, cyclic voltammetry, and elemental analysis. Theoretical calculations invoking singlet state geometry optimization, solvation effects, and noncovalent interactions were done using density functional theory (DFT). DFT calculations were also applied to evaluate the electronic properties, and time-dependent DFT was applied to clarify experimental UV-vis results. Cytotoxicity for cancerous and noncancerous human cell lines was evaluated with cell viability MTT assay. Complexes demonstrated a moderate cytotoxic effect toward cancerous human cell line PANC-1. The catalytic activity of the complexes was evaluated in transfer hydrogenation of aryl ketones. All complexes exhibited good catalytic activity and functional group tolerance.

Biological evaluation and molecular dynamics simulation of water-soluble fullerene derivative C60[C(COOH)2]3.

One of the most studied fullerene members, C60, has a potential of application in various fields of biomedicine including reactive oxygen species (ROS) scavenging activity, inhibiting of tumours development, inactivating of viruses and bacteria, as well as elaboration of diagnostic and targeted drug delivery tools. However, the hydrophobicity of this molecule impedes its practical use, therefore the actuality of the research devoted to functionalisation of fullerenes leading to amphiphilic derivatives remains important. In this work, the water-soluble carboxylated fullerene derivative C60[C(COOH)2]3 was studied. Extensive biomedical investigation of this compound, namely, the binding with human serum albumin (HSA), radical scavenging activity in the reaction with diphenylpicrylhydrazyl (DPPH) radical, photodynamic properties, cytotoxicity in human embryonic kidney (HEK293) cell line, erythrocytes' haemolysis, platelet aggregation, and genotoxicity in human peripheral mononuclear cells (PBMC) was conducted. Moreover, the dynamic and structural characteristics of C60[C(COOH)2]3-H2O binary system were obtained using molecular dynamic (MD) method, and size distribution of C60[C(COOH)2]3 associates was measured.

Non-natural 2H-azirine-2-carboxylic acids: an expedient synthesis and antimicrobial activity.

Non-natural 2H-azirine-2-carboxylic acids were obtained in high yields by FeCl2-catalyzed isomerization of 5-chloroisoxazoles to azirine-2-carbonyl chlorides followed by their hydrolysis. The 3-aryl- and 3-heteroaryl-substituted acids are stable during prolonged storage, exhibit antibacterial activity against ESKAPE pathogens and show a low level of cytotoxicity.