烷基化壳聚糖的制备及止血效果

Alkylated-chitosan preparation and its hemostatic effect

BACKGROUND: 18-Alkylated-chitosan has been proved to exhibit a good coagulation capacity through hydrophobic modification.OBJECTIVE: To improve the adhesion between the material and the wound through the introduction of alkylated-chitosan molecules.METHODS: The alkyl group was introduced in the chitosan by potentiodynamic method to prepare the alkylated-chitosan with different substitution degrees (7%,16%, 26% and 40%), and then their structure, viscosity, porosity, water absorption, contact angle and in vitro coagulation capacity were detected. Thirty New Zealand rabbits were enrolled, modeled into the left femoral artery hemorrhage, and randomized into six groups, including four experimental groups, positive control and control groups, followed by treated with alkylated-chitosan sponges with different degrees of substitution, absorbable hemostatic gauze and chitosan sponge, respectively. Afterwards, the blood loss and clotting time were observed.RESULTS AND CONCLUISON: With the degree of substitution increased, the viscosity of alkylated-chitosan increased firstly and then decreased, the porosity and water absorption decreased gradually, and the contact angle on a rise. Compared with chitosan, different alkylated-chitosans showed a better henostatic effect in vitro, especially the alkylated-chitosan with 16% substitution degree. The blood loss and clotting time in the experimental groups except that the alkylated-chitosan with 7% substitution degree were significantly lower than those in the control group (P < 0.05); the bold loss in the alkylated-chitosan with 40% substitution degree group was significantly lower than that in the positive control group (P < 0.05). These findings suggest that the alkylated-chitosan with 40% substitution degree exhibits the best hemostatic effect in vivo.