Freeze-Dried Carboxymethyl Chitosan/Starch Foam for Use as a Haemostatic Wound Dressing

Prolonged bleeding is a general complication that occurs after tooth extraction or oral surgery. Thus, patients must apply pressure and use absorbable wound dressings to stop bleeding and prevent blood loss. This method stops bleeding and causes clotting of blood. However, some people have bleeding disorders or cannot stop bleeding with applied pressure after oral surgery. Therefore, haemostatic foam dressing is an interesting material that can be used to stop bleeding without hindering blood clotting in the wound site. In this study, foam was prepared using a blend of starch with carboxymethyl chitosan and glyoxal as a crosslinking agent. The foam was formed by freeze-drying. Carboxymethyl chitosan/starch foam absorbed water rapidly and held it, as analysed by a blood clotting assay and maximum swelling. Thus, carboxymethyl chitosan/starch foam (CM/starch foam) made with a 1:4 ratio and with 1% glyoxal also absorbed blood very well and exhibited suitable properties. Cytotoxic studies using human dermal fibroblast cells, as determined by MTT assay, confirmed that CM/starch foam was non-toxic and had good mechanical properties in a wet environment.