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V Davankov

Publications and source records attributed to V Davankov.

8 recordsLinked to original sources
PubMed2002

Hypercross-linked polystyrene and its potentials for liquid chromatography: a mini-review.

Hypercross-linked polymeric adsorbing materials are obtained under conditions that (i) their polymeric network is formed in the presence of large amounts of a thermodynamically good solvent (porogen) and (ii) the network is rigid. Hypercross-linked polystyrene is a transparent microporous low-density material with an apparent inner surface area of over 1,000 m2/g and an unprecedented adsorption capacity. To enhance the mass transfer, the adsorbent beads may be provided with large transport pores, in addition to the inherent micropores; these beads are opaque. Hypercross-linked polystyrene sorbents are widely used for large scale adsorption of organic compounds from aqueous and gaseous media and for solid-phase extraction of trace components. Novel perspective application areas of the materials are high-performance liquid chromatography column packings and blood purification. Present mini-review summarises basic principles of obtaining hypercross-linked materials, their structural peculiarities and distinguishing properties, as well as major application areas. Important new unpublished data are also included.

Adsorption↗
PubMed2000

Polymeric adsorbent for removing toxic proteins from blood of patients with kidney failure.

A hypercrosslinked styrenic polymer with an enhanced proportion of mesopores in the range 2-20 nm has been developed. The principle of the synthesis consists of the suspension polymerization of divinylbenzene (or copolymerization of styrene with divinylbenzene) in the presence of a porogen that is a theta-solvent for polystyrene. On the scale of thermodynamic affinity, theta-solvents occupy a border position between good solvents and precipitating media for the growing polymer chains. In this case, microphase separation takes place during the final stages of the polymerization process. The polymer was shown to adsorb 93-98% of beta2-microglobulin from the blood or plasma of patients with chronic kidney failure. At the same time, large essential proteins, like albumin, are not removed to a significant extent, obviously, due to the size-exclusion effect and the difference in the hydrophobicity of the proteins. By replacing surface exposed pendant vinyl groups of the polymer with hydrophilic functional groups, the material was made hemocompatible, according to the standard battery of biocompatibility tests required by ISO 10993 guidelines. No adverse effects such as fever or hypotension were noted in dogs in direct hemoperfusion experiments with the polymer.

Adsorption↗
PubMed1994

Polyvinylpyrrolidone-coated silica packings for chromatography of proteins and peptides.

Polyvinylpyrrolidone (PVP)-coated silica sorbents were synthesized by interaction of a copolymer of vinyl-methyldiethoxysilane and vinylpyrrolidone with LiChrospher Si 300 and LiChrospher Si 500 silicas. The coating procedure retains the wide-pore structure of the starting silicas, as was shown by nitrogen adsorption, mercury porosimetry and inverse size-exclusion chromatographic measurements. Good selectivity and separation ability of the synthesized packings toward proteins and peptides were demonstrated in the hydrophobic interaction chromatographic mode of separation. Aromatic compounds undergo a specific interaction with bonded PVP chains which can be used for the preconcentration or selective recovery of polycyclic aromatic hydrocarbons.

Amino Acid Sequence↗