Search results

Sort By:

Limit search:

THE INHIBITION OF HUMAN PLATELET AGGREGATION BY A LOW-MOLECULAR WEIGHT CHITOSAN

100%

Drozd N. N., Logvinova Y. S., Shagdarova B. T., Il’ina A. V., Varlamov V. P.

Progress on Chemistry and Application of Chitin and its Derivatives

2018

vol. 23

55 - 65

Chitosan derivatives were obtained by chemical (MW of 6 kDa, DD 99% - Ch6/99; MW13 kDa, DD 98% - Ch13/98) and enzymatic (MW of 5 kDa, DD 85% - Ch5/85; MW of 10 kDa, DD 85% - Ch10/85) depolymeri-sation of chitosan with a MW of 334 and 1000 kDa. Chitosan derivatives (almost identical MW pairs and different DD) possessed insignificant an-ticoagulant activity, did not promote human platelet aggregation and re-duced ADP or collagen-induced platelet aggregation. The studied sam-ples at a concentration of 2 mg/ml reduced the aggregation of platelets more than twice induced in 2x10-6M and 1x10-5M concentrations; at weak activation in 2x10-6M, the Ch10/85 sample was the most effective. The Ch6/99 and Ch13/98 samples were 20 times more effective at the inhibi-tion of collagen-induced platelet aggregation than the Ch10/85 sample. The latter can be explained by the greater value of positive charge (DD) and polydispersity (Mw/Mn) of chitosan samples obtained by chemical de-polymerisation

THROMBORESISTANT SILICON PLATES MODIFIED WITH CHITOSAN AND HEPARIN BY THE LAYER-BY-LAYER ASSEMBLY METHOD

73%

Drozd N. N., Shagdarova B. T., Zhuikova Y. V., Il’ina A. V., Vasiliev M. N., Vasilieva T. M., Hein A. M., Varlamov V. P.

Progress on Chemistry and Application of Chitin and its Derivatives

2019

vol. 24

5 - 22

Fifteen samples of silicone plates (PlateSi, area=12 cm2), with surfaces modified layer-by-layer with chitosan and unfractionated heparin, were obtained. The sample surfaces were pre-treated by cold oxygen plasma in a planar-type plasma chemical reactor with 50 W power before coating with layered polysaccharides. Pre-treatment was carried out in two alternative operation modes of the reactor, namely in the plasma etching mode and in the reactive-ion etching mode. Thromboresistance was assessed in vitro in contact with human blood. The thromboresistant silicon plates, modified layer-by-layer (3, 5, 7, and 9 bilayers) with chitosan, with molecular weights of 65 kDa, increased with the increase in the number of layers, up to 5. An increase in the duration of thromboresistance was observed in layer-by-layer modification of the surface of the plates with chitosan with a molecular weight of 200 kDa or with quaternized chitosan with a molecular weight of 200 kDa. Some samples of highly thromboresistant, modified PlateSi contributed to the adhesion of platelets and the haemolysis of red blood cells to a lesser extent than untreated silicon plates. The three most promising samples of modified PlateSi were selected.

Refine search results

2 Progress on Chemistry and Application of Chitin and its Derivatives

1 2019

1 2018

2 Drozd N. N.

2 Il’ina A. V.

2 Shagdarova B. T.

2 Varlamov V. P.

1 Hein A. M.

1 Logvinova Y. S.

1 Vasiliev M. N.

1 Vasilieva T. M.

1 Zhuikova Y. V.

Search results

THE INHIBITION OF HUMAN PLATELET AGGREGATION BY A LOW-MOLECULAR WEIGHT CHITOSAN

THROMBORESISTANT SILICON PLATES MODIFIED WITH CHITOSAN AND HEPARIN BY THE LAYER-BY-LAYER ASSEMBLY METHOD