Self-Assembled Quaternary Ammonium-Containing Comb-Like Polyelectrolytes for the Hydrolysis of Organophosphorous Esters: Effect of Head Groups and Counter-Ions.

The aim of this work was to increase the efficiency of catalytic systems for the hydrolytic cleavage of 4-nitrophenyl esters of phosphonic acids. Quaternary ammonium-containing comb-like polyelectrolytes («polymerized micelles») with ester cleavable fragments and a low aggregation threshold were used as catalysts. The synthesis of poly(11-acryloyloxyundecylammonium) surfactants with different counterions (Br , NO , CH C H SO ) and head groups was realized by micellar free-radical polymerization.

Poly(D,L-lactide)/PEG blend films for keratinocyte cultivation and skin reconstruction.

The objective of this study was to develop a novel porous thin poly(D,L-lactide) (PLA) film as a tissue-engineering scaffold for keratinocytes used for the replacement of damaged skin. Poly(D,l-lactic acid)/poly(ethylene glycol) (PEG: Mw 6000 or 15 000) blend films were formed by a spin coating technique. The properties and structures of these blend films were investigated.

Novel surfactant-selective membrane electrode based on polyelectrolyte-surfactant complex.

Novel class of active ionophores for surfactant selective electrodes is proposed. PVC membrane doped with polyelectrolyte-surfactant stoichiometric complex is used for ion-selective electrode construction responsive to cetyltrimethyl ammonium bromide and related surfactants. New ionophore is quite stable and completely insoluble in aqueous media in wide range of pH.

[Cultured skin cells interaction with polylactide surface coated by different collagen structures].

The purpose of this work was an optimization of polylactide film surfaces designed for human keratinocytes cultivation. The polylactide films were coated by collagen 1. The experiments showed that uniform covering of polymer surface by collagen, and formation of different collagen structures depend on the mode of the protein application.

[Elaboration of biodegradable polymer substrate for cultivation of human dermal fibroblasts].

The influence of polylactic acid (PLA) surface films on the pattern of cell behavior was studied. The human dermal fibroblasts were cultivated on PLA covered glasses. The hydrophobic nature of PLA films depends on the availability of polymer solvent in the film preparation.

Dynamic surface properties of poly(N-isopropylacrylamide) solutions.

The dynamic surface elasticity of aqueous solutions of poly(N-isopropylacrylamide) (pNIPAM) has been measured by the oscillating barrier and capillary wave methods as a function of time and concentration. While the real and imaginary parts of the surface elasticity almost did not change with the concentration, their kinetic dependencies proved to be nonmonotonic. Simultaneous measurements of the film thickness and adsorbed amount by null-ellipsometry showed that the pNIPAM adsorption can be divided into two steps corresponding to the formation of a concentrated narrow region close to the air phase and a region of tails and loops protruding into the bulk liquid.

Dilational surface viscoelasticity of polymer solutions.

A review of recent results on the dilational surface viscoelastic properties of aqueous solutions of non-ionic polymers is given. In the frequency range from 0.001 up to 1000 Hz the methods of transverse and longitudinal surface waves and the oscillating barrier method were applied.

[Modern antibiotics in the clinical picture of infectious diseases].

The number of various chemotherapeutics including antibiotics used in combined treatment of patients with various infectious diseases is rather significant. Recently some new valuable drugs have been recommended. Still, in spite of definite achievements in treatment of patients with infectious diseases there are some difficulties and problems mainly connected with therapy of patients with sepsis, chronic typhoid fever bacterial carriers and some other patients.

[Quantitative determination of specific immunoglobulins in the serum of bacterial carriers of abdominal typhus].

As a result of determination of immunoglobulins of class A and M by the method of simple radial immunodiffusion with the use of monospecific antiglobulin sera it appeared that in the sera of carriers immunogolubins M were contained in much lesser quantity than in typhoid patients. The content of immunoglobulins A was somewhat greater in the blood sera of carriers.