State and Properties of a Carbon Sorbent Modified with a Bioactive Substance

A method for introducing small amounts of betulin (up to 1 wt %) into a mesoporous carbon material with a preset specific surface area of 300–310 m 2 /g, total specific pore volume of 0.35–0.40 cm 3 /g, and average pore diameter of 5.2–5.5 nm has been proposed and studied. The betulin content in the solid carbon matrix and in the used organic solvents has been determined by means of a gas chromatography–mass spectrometry technique. By means of scanning electron microscopy together with X-ray microanalysis and IR Fourier spectroscopy, the state of betulin on the outer and inner surfaces of carbon granules of different fractional composition, as well as in thin carbon layers, has been studied. It has been found that the main fraction of betulin is predominantly deposited on the outer surface of the globular particles of a porous carbon material. The properties of betulin impregnated into a carbon sorbent and the process of its dynamic desorption under the conditions simulating the biological environment of the gastrointestinal tract are studied.