RESUMO
Using a [3H]-labelled polyelectrolyte as a tracer, the 60Co grafting of a synthetic heparinoid polyelectrolyte onto silicone rubber was studied. The polyelectrolyte was labelled by the coupling of a radioactive amine to carboxylate groups of the polyelectrolyte. The amount of grafted polyelectrolyte was found to be dependent on the radiation dose.
Assuntos
Prótese Vascular , Heparinoides , Polímeros , Elastômeros de Silicone , Adsorção , Materiais Biocompatíveis , Butadienos , Etanolaminas , Etildimetilaminopropil Carbodi-Imida , Raios gama , TrítioRESUMO
Gamma irradiation of aqueous solutions of a synthetic heparinoid polyelectrolyte results in the formation of hydrogels, varying in water content and mechanical strength. The equilibrium water content and the mechanical strength of the hydrogels are dependent on the initial polyelectrolyte concentration, the molecular weight of the polyelectrolyte, the percentage of double bonds in the polyelectrolyte and the radiation dose. The polyelectrolyte hydrogels do not deplete Antithrombin III from blood and there is no activation of factor XII according to an in vitro kallikrein generation test. However, in a very sensitive test for factor XII activation (contact promoted shortening of the thrombotest) a slight activation of this factor was observed.
Assuntos
Materiais Biocompatíveis , Heparina , Heparinoides/efeitos da radiação , Polietilenoglicóis , Polímeros/efeitos da radiação , Fator XII/metabolismo , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato , Calicreínas/metabolismo , Polietilenoglicóis/farmacologiaRESUMO
Addition of chlorosulfonyl isocyanate to C==C bonds in cis-1,4-polyisoprene and reaction of the adduct with NaOH resulted in the formation of a water-soluble polyelectrolyte with N-sulfate and carboxylate groups. The polyelectrolyte showed anticoagulant activity and it was found, just as with heparin, that the activity was related to molecular weight and N-sulfate content.
