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Biomedical subjects

M Reháková

Publications and source records attributed to M Reháková.

8 recordsLinked to original sources
PubMed1996

Properties of collagen and hyaluronic acid composite materials and their modification by chemical crosslinking.

This article describes properties of composites of collagen-hyaluronic acid shaped to layered materials. According to the results, interactions of these two polymers are very strong. The properties can be influenced by chemical crosslinking using glyoxal and starch dialdehyde. The different behavior during enzymatic degradation by collagenase and in swelling experiments is discussed in relation to material composition. The valuable properties of the composites observed in this study show the possibility of their use as biomaterials.

Achilles Tendon↗
PubMed1994

Depolymerization reactions of hyaluronic acid in solution.

Samples of microbial sodium hyaluronate were degraded by heating, ultrasonication ultraviolet (UV) and gamma-ray irradiation and enzymatic treatment. The weight-average molecular weight, Mw, of hyaluronate in 0.15 M NaCl and 0.06 M Na2HPO4 was determined by gel filtration with UV detection. The Mw of the degraded samples varied from 8 x 10(4) to 1.38 x 10(6). Depolymerization processes can be described by linear relationship (1/Mw)2 = f(t) in the case of ultrasonic treatment and by non-linear relationships in the cases of heating and UV irradiation at 257 nm. Gamma-ray irradiation and enzymatic treatment caused chemical degradation and depolymerization to oligosaccharides, respectively.

Animals↗
PubMed1994

Modification of layered atelocollagen by ultraviolet irradiation and chemical cross-linking: structure stability and mechanical properties.

Physical and chemical modifications of atelocollagen materials have been carried out to improve their physical, chemical and biological properties. We have studied the influence of physical modification using ultraviolet irradiation and of chemical modification using hexamethylene diisocyanate on the physical properties of layered atelocollagen materials. The study evaluated the structural stability of cross-linked materials using swelling experiments. Influence on mechanical properties is also discussed.

Animals↗
PubMed1993

[Biomaterials based on collagen].

The review deals with collagen which is an essential natural polymer for preparing of biomaterials used in different fields of medicine. Besides discussing the structure of the basic polymer, the antigenicity of collagen materials as well as the bioactive properties of the collagen implants are described. The substantial part of the paper is oriented to the bioengineering processes of the preparation of the collagen matrix and composite structures. For these the physical and chemical modification of collagen are used. The processes of the modification are shown to be important in the fixing of the structure, improving the mechanical properties and influencing and directing the resorption of collagen materials in organism. Two types of materials are subdued to a detailed discussion. One which is combined with glycosoaminoglycanes and serves as the temporary skin cover and the second type, the structure of which, in the combination with hydroxylapatite imitates bone. (Tab. 4, Ref. 22.)

Animals↗