Infrared spectra of carbon hemosorbents

Abstract

541.183.6;543.42 Elemental analysis and Fourier-transform IR spectroscopy methods have been used to study the structure of two carbon hemosorbents that differ from one another in the way of synthesis. The hemosorbents contain C, N, H, S, and O atoms. Analysis of IR spectra has shown that the hemosorbents have different amounts of C=O carbonyl groups in the bulk than on the surface with the same proportion of OH-and C=C groups throughout the sample. This was observed experimentally as a change of intensity and position of the corresponding vibrational absorption bands. The possibility in principle of using the proposed analytical methods to establish structural features of hemosorbents both on the surface and within the sample is substantiated.Introduction. Carbon hemosorbents (CHS) have been successfully used in clinical practice to treat endogenous intoxication syndrome that accompanies several diseases [1][2][3]. The therapeutic effect from use of CHS is achieved by removing from the organism various hydrophobic and hydrophilic metabolites and toxins. CHS in contact with blood should have high mechanical strength, exhibit sorption activity, traumatize minimally blood components and living tissue, provide the required hydrodynamics and kinetics for hemocarboperfusion processes, and lack toxic, cancerogenic, and allergic properties [3,4]. The manifestation of the aforementioned medical and biological properties depends in principle on the CHS preparation method.The CHS preparation conditions affect the formation of the carbon structure of the hemosorbent skeleton in general and the formation in it of active sorption centers. As a rule, CHS are based on activated charcoals that are graphitic solids [5,6]. The main structural element in the bulk and on the surface of CHS is a system of condensed aromatic rings in which three valence electrons of carbon are bonded to neighboring atoms by strong and fully saturated σ-bonds whereas the fourth π-electron is practically fully delocalized and can freely migrate along the system of conjugated bonds. The surface C atoms in condensed aromatic rings exist in an electronic and energy state that is different from that in the bulk and are capable of reacting with various elements and compounds to form unconventional surface compounds such as functional groups and surface complexes including O, N, S, P, and other atoms.An IR spectroscopy study of CHS structural features can solidify concepts about their medical and biological properties and reveal practically important correlations, e.g., structure-spectrum-detoxification properties. We used elemental analysis and IR-Fourier spectroscopy to study the chemical composition and structure of two carbon hemosorbents that are widely used in biomedical practice.Experimental. The starting material for preparing CHS was macroporous ion-exchange resin based on a polystyrenedivinylbenzene matrix with large pore volumes and sizes [7]. The porosity of the starting material can decrease sharply during thermal and thermal chemical destruct...

Mechanism of Copper and Tert-Butyl Alcohol Adsorption on Carbon Materials at Various Open-Circuit Potentials

“…The problem of creating new carbon-based hemosorbents is an important one at the present time [1]. When analyzing factors that influence the interaction of carbon-based sorbents with biological media, most authors, such as [1], focus on the reactivity and composition of the functional groups on the surface, as well as defects in the carbon structure (sharp edges, dislocations, and surface heterogeneity). However, as shown in [2], the interaction of activated carbons with blood cells in the sorbent/blood system is due to the electrochemical properties of both the carbon and the blood cells.…”