Biodegradation of KL-3 Polyurethane Adhesive

The biodegradation of KL-3 as a hardened composition was studied [419- 23]. The degradation of KL-3 in animal tissues is facilitated by two mutually complementary mechanisms nonenzymatic hydrolysis, and cellular processes. 

The acellular (hydrolytic) mode of hiodegradation is identical in model media in vitro) and in hving organisms in vivo). It consists in hreaking ester urethane, and then ether bonds [423, 424]. Biodegradation of polyurethane is also accompanied hy hreaking of the secondary hiiu ethic and allophane bonds, a decrease in the effective density of the polymer suture, and a change in its supramolecular structure [422—424], 

Study of the cellular type of biodegradation was possible as a result of investigations on the spedfic staining of polyurethane fragments in archived preserved preparations with the use of Sudan III-IV stain [425, 426]. Binding of polymer fragments to this stain produces a red-orange color, which makes it possible to identify not only free polyurethane particles but also intracellular particles. 

The products of biodegradation of I01i-3 polymeric films are excreted by the organism via the ludnaiy system and the gastrointestinal tract and do not accumulate in tissues and organs [428]. 

Response of tissues to KL-3 adhesive. The use of medical adhesives on organs and tissues represents a reliable methodology that allows amelioration of the traumatic consequences of surgical operations. 

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