Platelet surface-related properties

Polymeric materials are used in a wide range of medical applications, because of their unique physical properties such as strength, elasticity, and pliability. A potential application could include small diameter vascular implants if one of the major problems of polymeric biomaterials in contact with blood, thrombus formation, could be overcome. Although the underlying processes are not completely understood, an initial step in the thrombogenic sequence is the adsorption of plasma proteins to the surface of a material followed by adhesion of platelets and/or leukocytes.2 3 The extent of thrombosis, in turn, is related to the... 

Related results have demonstrated that CS/HA multilayer-coated NiTi disks have better antifouling properties than unmodified NiTi disks, as demonstrated by a decrease in the adhesion of platelets in an in vitro assay (38% reduction). This result may be attributable to the hydration layer that surroimds HA molecules on the surface of the disks [152]. The hydrogel-Uke surface that is formed by the multilayers exhibited good hemocompatibility. 

Inadequate membrane biocompatibility elicits a variety of responses, including activation of the coagulation and complement system, activafion of platelets and leukocytes, production of cytokines and free oxygen radicals, and accumulation of bradykinin. Although they initiate locally, these responses cause systemic changes to the blood and the body behavior. They may also change the surface and transport properties of the membranes used. However, it should be recalled that the treatment of bio(in)compatibility is not solely related to the biomaterials used but rather depends also on the blood fluid dynamics in the membrane device and the whole extracorporeal blood circulation loop, as well as on how blood is handled in extracorporeal circulation. 

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