V. N. Postnov

Targeted drug delivery into reversibly injured myocardium with silica nanoparticles: surface functionalization, natural biodistribution, and acute toxicity

The clinical outcome of patients with ischemic heart disease can be significantly improved with the implementation of targeted drug delivery into the ischemic myocardium. In this paper, we present our original findings relevant to the problem of therapeutic heart targeting with use of nanoparticles. Experimental approaches included fabrication of carbon and silica nanoparticles, their characterization and surface modification. The acute hemodynamic effects of nanoparticle formulation as well as nanoparticle biodistribution were studied in male Wistar rats. Carbon and silica nanoparticles are nontoxic materials that can be used as carriers for heart-targeted drug delivery. Concepts of passive and active targeting can be applied to the development of targeted drug delivery to the ischemic myocardial cells. Provided that ischemic heart-targeted drug delivery can be proved to be safe and efficient, the results of this research may contribute to the development of new technologies in the pharmaceutical industry.

Passive targeting of ischemic-reperfused myocardium with adenosine-loaded silica nanoparticles

Pharmacological agents suggested for infarct size limitation have serious side effects when used at cardioprotective doses which hinders their translation into clinical practice. The solution to the problem might be direct delivery of cardioprotective drugs into ischemic-reperfused myocardium. In this study, we explored the potential of silica nanoparticles for passive delivery of adenosine, a prototype cardioprotective agent, into ischemic-reperfused heart tissue. In addition, the biodegradation of silica nanoparticles was studied both in vitro and in vivo. Immobilization of adenosine on the surface of silica nanoparticles resulted in enhancement of adenosine-mediated infarct size limitation in the rat model. Furthermore, the hypotensive effect of adenosine was attenuated after its adsorption on silica nanoparticles. We conclude that silica nanoparticles are biocompatible materials that might potentially be used as carriers for heart-targeted drug delivery.

Phase equilibria in fullerene-containing systems as a basis for development of manufacture and application processes for nanocarbon materials

This review is the first attempt to integrate the available data on all types of phase equilibria (solubility, extraction and sorption) in systems containing light fullerenes (C60 and C70). In the case of solubility diagrams, the following types of phase equilibria are considered: individual fullerene (C60 or C70)–solvent under polythermal and polybaric conditions; C60–C70–solvent, individual fullerene–solvent(1)–solvent(2), as well as multicomponent systems comprising a single fullerene or an industrial mixture of fullerenes and vegetable oils, animal fats or essential oils under polythermal conditions. All published experimental data on the extraction equilibria in C60–C70–liquid phase(1)–liquid phase(2) systems are described systematically and the sorption characteristics of various materials towards light fullerenes are estimated. The possibility of application of these experimental data for development of pre-chromatographic and chromatographic methods for separation of fullerene mixtures and application of fullerenes as nanomodifiers are described. The bibliography includes 87 references.

Solubility and some properties of aqueous solutions of fullerenol-d and composition of crystal hydrates

Method of isothermal saturation in ampules was used to study the solubility of fullerenol in distilled water in the temperature range 20–80°C and to determine the composition of its equilibrium crystal hydrates. The pycnometric technique was employed to examine how the density depends of the concentration of fullerenol solutions and the average molar and partial molar volumes of the components in solution at 25°C was calculated. The method of refractometry was used to study the dependence of the refractive index on the concentration of fullerenol solutions and the specific refraction of the solutions was calculated.

Targeted drug delivery to ischemic heart with use of nanoparticulate carriers

Purpose – Clinical outcome in patients with ischemic heart disease can be significantly improved with the implementation of targeted drug delivery into the ischemic myocardium. The purpose of this paper is to review the data of recent literature and present original findings relevant to the problem of therapeutic heart targeting with use of nanoparticles.Design/methodology/approach – For literature review, a public‐domain database (Medline) was searched using a web‐based search engine (PubMed) and the following key words: “nanoparticles”, “nanocarriers”, and “targeted drug delivery”. Experimental approaches included fabrication of carbon and silica nanoparticles, their characterization and surface modification. The acute hemodynamic effects of nanoparticle formulation as well as nanoparticle biodistribution were studied on male Wistar rats.Findings – Carbon and silica nanoparticles are biocompatible materials that can be used as carriers for heart‐targeted drug delivery. Concepts of passive and active tar...

Nafion-based composite solid electrolytes containing carbon nanotubes

Nafion-based composite solid electrolytes containing multiwalled carbon nanotubes have been studied by impedance spectroscopy. The effect of carbon nanotube morphology on the proton conductivity of the composites has been estimated at low relative humidity. Surface modification of carbon nanotubes with acidic groups increases the proton conductivity.

Fe3O4·C and ZrO2·Fe3O4·C nanostructures: Synthesis and characterization

A procedure for the synthesis of carbon-encapsulated multilayer magnetite and zirconium oxide–magnetite nanoparticles that form porous nanostructures, for use as biocompatible sorbents, is proposed. The properties, composition, dimensions, particle shapes, surface morphology, and magnetic characteristics of the products are studied.

Extraction of fullerene mixture from fullerene soot with organic solvents

Investigation of extraction of fullerene mixture from the fullerene soot obtained by plasma erosion of graphite rod in helium atmosphere with different solvents such as α-chloronaphthalene, o-dichlorobenzene, o-xylene, toluene, benzene, carbon tetrachloride, and n-hexane at 25°C was carried out. Completeness and effectiveness of extraction as well as relative content of light (C60, C70) and heavy (C76, C78, C84) fullerenes in the extract were evaluated.

Electrochemical properties of aqueous solutions of fullerenol-d

Dependence of the pH value on the concentration of fullerenol solutions was studied by means of pH-potentiometry, and the apparent degree of dissociation and the dissociation constant of fullerenol were calculated. The dependence of the electrical conductivity of fullerenol solutions on their concentration was examined. The molar electrical conductivity and also the apparent degree of dissociation and the dissociation constant of fullerenol were calculated.

Temperature Dependence of Solubility of Light Fullerenes in Some Essential Oils

Polythermal solubility of individual light fullerenes (C60, C70) and industrial fullerene mixture (60% С60, 39% С70, 1% С76–90) in some essential oils (e.g., essential oil of coriander, cypress, hazel, carnation, cade (leafage), cade (wood), cedar) is investigated. Temperature dependences of solubility are presented and characterized.