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A study was made of the applicability of supercritical antisolvent precipitation to producing microparticles of the antiasthmatic drug salbutamol sulfate that are suitable for manufacturing the drug in inhalation dosage form. Depending on the salbutamol concentration in the initial solution, the flow rate of the solution, and pressure, either spherical or needle-like particles 0.7–8.5 μm in size form. The dependence of the average particle size on the salbutamol concentration in the initial solution is nonmonotonic. The conditions were determined under which the obtained salbutamol particles meet the shape and size requirements for fabrication of inhalation dosage forms.

The work is devoted to exploring the possibility of using supercritical fluids as media for modification of polymers offering promise for production of gas-separation membranes with the goal to improve selectivity towards CO2. The possibility is demonstrated for introduction of fragments of quaternary ammonium salts into the structure of poly(4-methyl-2-pentyne) with the help of a two-stage process: bromination of the initial polymer with N-bromosuccinimide followed by the addition of the tertiary amine—N-butylimidazol— conducted in supercritical fluids as a medium. The use of trifluoromethane as the reaction medium provides the highest degree of modification of the brominated polymer with the amine. The polymer produced under the optimized conditions demonstrates a threefold increase of the calculated selectivity of separation of CO2 and N2 in comparison with the initial poly(4-methyl-2-pentyne).

Cytotoxicity and in vitro degradation rate of porous matrices based on lactide and e-caprolactone copolymers formed via supercritical foaming are determined. A high biocompatibility of materials obtained by the above method is demonstrated.

The capability of arbidol microparticle preparation by supercritical antisolvent (SAS) precipitation was demonstrated. A nonmonotonic dependence of the average particle size on the concentration was found, while the position of the minimum is dependent on the type of solvent used. It is possible to prepare Arbidol particles of various morphology and size from several microns to several hundred microns depending on the conditions.

Nanosized composites based on multiwall carbon nanotubes (CNTs) and Al2O3 have been obtained for the first time in supercritical (SC) media (water, hexane, and their mixture). For comparison, materials of the same net composition have been prepared by hydrothermal synthesis and sol–gel processing. The composites have been characterized by electron microscopy, X-ray diffraction, and thermal analysis. The structure of the materials synthesized in the SC media depends on the fluid composition. The most uniform composite containing alumina particles that are comparable in size to the CNT diameter and are stabilized on the carbon surface can be obtained in the SC mixture of hexane and water. When water and hexane are used separately, the formation of large alumina crystals on the CNT surface and contamination of the composite by the products of hexane pyrolysis and carbonization are, respectively, observed.

Micronization of hydroxypropylmethylcellulose using supercritical antisolvent (SAS) method is studied. The influence of various parameters, such as solvent type, polymer concentration, pressure, solution to supercritical CO2 flow rate ratio on morphology of particles is discussed. The possibility of obtaining spherical or elliptical shape hydroxypropylmethylcellulose particles of submicron size (190–620 nm) that depends on the process parameters is demonstrated.

Lipids are produced with a 60 wt % yield in terms of dry biomass in the course of fermentation of oleaginous fungi at 27–28°C for 4–5 days. Triglycerides are extracted by supercritical carbon dioxide in a flow regime at 80–100°C and 50 MPa. The fatty acid methyl esters (FAME) are synthesized via a two-step transesterification of triglycerides with a 98% yield. It is demonstrated using a combined method of chromatography-mass spectrometry that the fatty acid composition of the fungal lipids from Cunninghamella echinulata is close to that of rapeseed oil.

Thermodynamic aspects of an innovative binary-mixture (BM) technology for increasing the productivity of oil-bearing beds that provides a substantial reduction of oil-well watering (compared to conventional steam heating) are discussed. Inorganic and organic ammonium nitrates (NH4NO3 and HOCH2NH 3 + NO 3 - respectively) are compared qua heat-producing components of a BM that also contains sodium nitrite as an initiator of nitrate decomposition. Effects of temperature and pressure on the product distribution and heat production in ethanolammonium nitrate decomposition are evaluated. Calculations of parameters in a near-well space taking into account the heat capacity of the surrounding rock layer show that temperature and pressure can exceed their critical values for both water and main oil fractions. As a result, conditions for an intense upward flow of water—oil fluid in an artificial gas-lift regime arise.