Marconi W, Galloppa A, Martinelli A, Piozzi A
Department of Chemistry, University of Rome La Sapienza, Roma, Italy.
Biomaterials. 1995 Apr;16(6):449-56. doi: 10.1016/0142-9612(95)98817-x.
In order to prepare polymers provided with better haemocompatibility with respect both to the coagulative cascade and to platelet aggregation and activation, we have synthesized new polyurethanes containing in the chain-extender [di(2-hydroxyethyl)hexadecylamine] both a long chain alkyl group (able to bond albumin) and a tertiary ammonium group able, after suitable quaternization reaction, to bind ionically significant amounts of heparin. The amounts of heparin and albumin bonded to the polymer films were determined spectrophotometrically. A biological in vitro evaluation of the heparinized and albuminized films was also carried out with respect to blood coagulation factors (by activated partial thromboplastin time measurements) and to platelet adhesion and activation (by platelet count and scanning electron microscopy examination). It was seen that the type of adsorption sequence for albumin and heparin, respectively, onto the various homo- and copolymer films, plays an important role on their biological properties; the possible mechanisms involved are also discussed on the basis of X-ray photoelectron spectroscopy and attenuated transmission reflectance evaluation of the polymer surfaces.
为了制备在凝血级联反应以及血小板聚集和活化方面具有更好血液相容性的聚合物，我们合成了新型聚氨酯，其扩链剂[二(2-羟乙基)十六烷基胺]中既含有长链烷基（能够结合白蛋白），又含有叔铵基团，经过适当的季铵化反应后，该叔铵基团能够离子性地结合大量肝素。通过分光光度法测定了结合到聚合物薄膜上的肝素和白蛋白的量。还针对血液凝固因子（通过活化部分凝血活酶时间测量）以及血小板黏附和活化（通过血小板计数和扫描电子显微镜检查）对肝素化和白蛋白化薄膜进行了体外生物学评估。可以看出，白蛋白和肝素分别在各种均聚物和共聚物薄膜上的吸附顺序类型对其生物学性质起着重要作用；还基于聚合物表面的X射线光电子能谱和衰减全反射评估讨论了其中可能涉及的机制。
