An N-substituted polyurea coating with high affinity for heparin.
ASAIO J
; 39(3): M319-21, 1993.
Article
in En
| MEDLINE
| ID: mdl-8268551
ABSTRACT
A new N-substituted polyurea with tertiary amino groups in the polycarbamidic chain (NPUTA) has been synthesized. The polymer is soluble in C1-C4 alcohols, has high adhesion to polar molds, and has high H2O uptake (130-150%). The material can be coated on many biomaterials (polyurethanes, charcoal hemosorbents, cellulosic hemodialysis membranes), and high amounts of heparin can be adsorbed onto treated surfaces. NPUTA cast from 0.5-3.5% ethanol solutions can absorb large amounts of heparin from anti-coagulant solution (40-60 micrograms/cm2) and heparinized plasma. Heparin release into phosphate buffered saline (PBS) solution or plasma is minimal. The influence of NPUTA solution concentration and pre-absorbed heparin on the protein adsorption, platelet adhesion, surface induced hemolysis, and complement activation of these films has been investigated. Radiolabeled protein assays, radiolabeled platelet assays, and other methods were used. It was shown that modified surfaces for the listed materials, with heparinization, demonstrate improved in vitro blood compatibility without any changes in functional properties. For example, treatment with NPUTA/heparin does not reduce sorption of middle molecules by activated charcoal hemosorbent, while markedly and significantly decreasing platelet adhesion and complement activation. NPUTA/heparin modified, glutaraldehyde treated bovine pericardium exhibited significantly reduced calcification in a rat subcutaneous implant model. Other ex vivo circulation experiments also confirm the blood compatibility of different NPUTA treated surfaces.
Search on Google
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Polymers
/
Materials Testing
/
Heparin
/
Extracorporeal Circulation
Limits:
Animals
/
Humans
Language:
En
Journal:
ASAIO J
Journal subject:
TRANSPLANTE
Year:
1993
Document type:
Article
Affiliation country: