Platelet adhesion and activation on polyethylene glycol modified polyurethane surfaces. Measurement of cytoplasmic calcium.

摘要: Polyurethane (PU) surfaces were modified by coupling polyethylene glycol (PEG; molecular weight, 1,000) chains carrying different terminal groups (PU-PEG1K-OH, PU-PEG1K-NH2, PU-PEG1K-SO3) and longer PEG (MW, 3,350; PU-PEG3.4K-OH). The PU have the same (1K) chain density. Surface induced platelet activation was evaluated measuring cytoplasmic free calcium concentration in platelets contacting surfaces, adhesion onto investigated vitro. Cytoplasmic levels PU-PEG-SO3 remained relatively constant, contrast to significant increase observed for PU-PEG-NH2, PU-PEG-OH, control surfaces. degree of clearly demonstrates that all graft prevented adhesion. Among PEG1K shows lowest In case grafted (PU-PEG3.4K-OH PU-PEG3.4K-Hep), both found prevent These results suggest grafting is more effective than shorter preventing because highly dynamic movement hydrated at interface. addition, vitro interaction dependent upon on series