Fibrin Fibroin

Precipitation potentials discussed in Chapter 6 are relevant in the context of injury potential [40]. It has been pointed out that precipitation of the electrolyte occurs at the negative electrode. In human body, the injured part of the protoplasmic structure is electrically negative with respect to the uninjured part. The sensation of injury seems to be associated with the clotting process, which involves the conversion of a soluble plasma protein, fibrinogen into an insoluble protein fibroin. When a blood vessel is damaged, the extrinsic clotting mechanism operates and fibrils of fibrin adhere to the injured vessel to form a clot. 

Natural polymers such as collagen, elastin, and fibrin make up much of the body s native extracellular matrix (ECM), and they were explored as platforms for tissue engineered constructs [34,47 9]. Polysaccharides such as chitosan, starch, alginate, and dextran were also studied for these purposes. Simultaneously, silk fibroin was widely explored for vascular applications due to its higher mechanical properties in comparison to other natural polymers, such as fibrin [48]. The utilization of natural polymers to create tissue-engineered scaffolds has yielded promising results, both in vitro and in vivo, due in part to the enhanced bioactivity provided by materials normally found within the human body [50]. However, their mechanical response is usually below the required values therefore, synthetic polymers have been explored to achieve the desired properties. 

For fabrication of biomimetic hydrogel for biomedical and pharmaceutical applications, a range of synthetic and protein-based polymer scaffolds, such as albumin, collagen, gelatin, elastin, proteoglycan, hyaluronan, laminin, silk fibroin, soybean, fibrinogen, and fibrin have been widely used (Rajangam and An, 2013). 

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