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.

Protective role of fullerenol and arginine C60 fullerene against copper toxicity in cucumber.

Copper (Cu), when in excess, is one of the most toxic and hazardous metals to all living organisms, including plants. Engineered nanomaterials have the potential for increasing crop protection. However, the protective role of fullerenes (carbon-based nanoparticles with wide application in various areas) against Cu toxicity in plants is, so far, understudied. The present study investigated whether fullerenes can potentially alleviate Cu toxicity in plants (Cucumis sativus L.). Two water-soluble fullerene C60 derivatives were examined: fullerenol [C60(OH)22-24] and arginine-functionalized fullerene [C60(C6H13N4O2)8H8], under controlled conditions using hydroponics. Plants treated with 15 µM of Cu exhibited typical symptoms of Cu toxicity: impaired growth, leaf chlorosis, reduced photosynthetic activity, nutritional imbalances, and enhanced lipid peroxidation. These symptoms were alleviated in the presence of fullerene derivatives with arginine C60 having the more pronounced effect. Improved cucumber Cu tolerance was attributable to Cu buffering in the root zone (roots and medium), which caused a dramatic decline in Cu transport towards leaves and the elimination of oxidative damage. The Cu removal efficacy of arginine C60 was much greater than that of fullerenol. These fullerenes acted in a dose-dependent manner and removed Cu selectively without significant modification of the bioavailability of other essential nutrients. Treatment with free arginine did not affect Cu immobilization or Cu toxicity. These results suggest that the surface chemistry of the fullerene core is important for the protection of plants under excessive Cu conditions. The information offered a new approach to preparing promising practical materials for alleviating Cu toxicity in plants with potential application in fields.

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.

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.

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.

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 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.

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.

Fullerenol changes metabolite responses differently depending on the iron status of cucumber plants.

The unique properties of carbon-based nanomaterials, including fullerenol, have attracted great interest in agricultural and environmental applications. Iron (Fe) is an essential micronutrient for major metabolic processes, for which a shortage causes chlorosis and reduces the yield of many crops cultivated worldwide. In the current study, the metabolic responses of Cucumis sativus (a Strategy I plant) to fullerenol treatments were investigated depending on the Fe status of plants. Cucumber plants were grown hydroponically, either with [+FeII (ferrous) and +FeIII (ferric)] or in Fe-free (-FeII and -FeIII) nutrient solution, with (+F) or without (-F) a fullerenol supply. Iron species-dependent effects were observed in either Fe-fed or Fe-starved plants, with alteration of metabolites involved in the metabolism of carbohydrates, amino acids, organic acids, lipophilic compounds. Metabolic perturbations triggered by fullerenol in the FeIII-treated plants were in the opposite kind from those in the FeII-treated plants. Whereas in the FeIII-fed plants, fullerenol activated the metabolisation of carbohydrates and amino acids, in the FeII-fed plants, fullerenol activated the metabolisation of lipophilic compounds and repressed the metabolisation of carbohydrates and amino acids. In FeIII-deficient plants, fullerenol stimulated the metabolism of C3 carboxylates and lipophilic compounds while repressing the metabolism of amino acids, hexoses and dicarboxylates, while in FeII-deficient plants, activations of the metabolism of amino acids and dicarboxylates and repression of sterol metabolism by fullerenol were observed. The results indicated that the valence state of Fe sources is of importance for re-programming metabolome responses in cucumber to fullerenol either in Fe-sufficient or Fe-deficient conditions. These investigations are significant for understanding fullerenol interactions and risk assessment in plants with different Fe statuses.

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.

Fullerenol increases effectiveness of foliar iron fertilization in iron-deficient cucumber.

The water-soluble fullerenols are novel carbon-based nanomaterials with unique properties, which afford them with wide agricultural applications. Iron (Fe) deficiency is the most common and widespread nutrition disorder affecting plants. Foliar Fe treatments of plants have been carried out with solutions devoid of fullerenol. In this study, the role of fullerenol [C60(OH)22-24] in alleviation of Fe deficiency in Cucumis sativus (a Strategy I plant) via foliar fertilization was investigated. Cucumber plants were grown hydroponically, either with (Fe) or in Fe-free (-Fe) nutrient solution. The following foliar spray treatments were applied: fullerenol at final concentrations of 1 (F1) and 10 (F10) mg L-1; Fe(II)SO4·7H2O; Fe(II)-EDTA (ethylenediaminetetraacetic acid); and Fe(II)-F1 and Fe(II)-F10. The best used compound was a combination of Fe(II)-sulfate with fullerenol, especially Fe-F1. The addition of fullerenol to Fe(II)-sulfate solutions significantly increased leaf-active Fe (extracted by an Fe(II) chelator) and re-greening at the site of application. The fullerenol-induced mutual influences did not appear when fullerenol was sprayed alone, suggesting a beneficial role of Fe(II)-fullerenol interactions in the penetration of Fe(II) in the leaves and re-greening under Fe-limited conditions. The results are of importance to enhancing the potential of foliar Fe fertilization as the commonly used strategy for ameliorating Fe deficiency and improving crop yield and quality.

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.