Abstract
Comparative studies have been carried out among solidβstate chitosan soliquoid, chitosan acetic acid physiological saline solution, and carboxymethyl chitosan physiological saline solution to discover the hemostatic effect of molecular weight (M~w~) and deacetylation degree (DA) of chitosan. It was found that solidβstate chitosan and chitosan acetic acid physiological saline solution performed different hemostatic mechanisms. When blood mixed with chitosan acetic acid physiological saline solution, the erythrocytes aggregated and were deformed. The DA, especially a low DA, in the chitosan acetic acid physiological saline solution, had a significant effect on the unusual aggregation and deformation of erythrocytes, compared with the effect of M~w~ within a range between 10^5^ and 10^6^. However, this phenomenon could not be observed in solidβstate chitosan soliquoid. Solidβstate chitosan with a low DA absorbed more platelets and was more hemostatic. Carboxymethyl chitosan physiological saline solution had nothing to do with the aggregation and deformation of erythrocytes but caused local rouleau. The values of thrombin time (TT), prothrombin time (PT), activated partial thromboplastin time (APTT), and fibrinogen concentration (FIB) were measured after the blood was mixed with solidβstate chitosan soliquoid, chitosan acetic acid physiological saline solution, and carboxymethyl chitosan physiological saline solution, separately. The results demonstrated that coagulation factors might not be activated by them. Β© 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2008