Blood response synthetic materials

Heparin, one of the most widely used blood anticoagulants, is an expensive product. Attempts have been made to prepare a number of synthetic anticoagulants, but none are as nontoxic as heparin. It has been reported that cellulose and starch sulfuric acid esters are toxic, whereas chitin disulfuric acid is less toxic. It has also been reported that the protein moiety of chitin is responsible for the inflammatory response when material containing chitin is injected into tissues of higher animals, whereas pure chitin does not give a detectable response. Dutkiewicz et al. [218] have shown that chitosan exhibits not only a hemostatic effect, but also has anticoagulant properties. Some variation... 

The most widely studied synthetic polymers for blood contact applications are polyether urethane ureas ( Biomer (Ethicon)). These materials have been used in artificial hearts, as coatings for lead wires in pacemakers, have been used and are being considered for blood vessel prostheses. The success of these materials is believed to be due to preferential adsorption of albumin rather than globulin or fibrinogen which promote a clotting response. However, these materials are hydrophobic and questions of long-term effectiveness are unresolved. Particularly, these materials may shed emboli or may be susceptible to surface calcification. Thus, it may be desirable to have synthetic polymers which are hydrophilic and better resemble blood vessels [475]. 

Biomedical materials include metals, ceramics, natural polymers (biopolymers), and synthetic polymers of simple or complex chemical and/or physical structure. This volume addresses, to a large measure, fundamental research on phenomena related to the use of synthetic polymers as blood-compatible biomaterials. Relevant research stems from major efforts to investigate clotting phenomena related to the response of blood in contact with polymeric surfaces, and to develop systems with nonthrombogenic behavior in short- and long-term applications. These systems can be used as implants or replacements, and they include artificial hearts, lung oxygenators, hemodialysis systems, artificial blood vessels, artificial pancreas, catheters, etc. 

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