Hemostatic properties of in situ gels composed of hydrophobically modified biopolymers.

Hemorrhaging often occurs during cardiac surgery, and postoperative bleeding is associated with medical complications or even death. Medical complications resulting from hemorrhaging can lead to longer hospital stays, thus increasing costs. Hemostatic agents are the main treatment for bleeding. In the present study, hemostatic agents composed of aldehyde groups and hydrophobically modified with hyaluronic acid (ald-hm-HyA) and hydrophobically modified gelatin (hm-ApGltn) were developed and their hemostatic effects were evaluated. These modified hemostatic agents formed more stable blood clots compared with the nonhydrophobically modified HyA-based hemostatic agent. The bulk strength of the whole blood clot using the aldehyde and stearoyl group-modified hyaluronic acid (ald-C18-HyA)/hm-ApGltn-based hemostatic agent was higher than that of the aldehyde group only modified HyA (ald-HyA)/hm-ApGltn-based hemostatic agent. Rheological experiments using α-cyclodextrin showed that hydrophobic modification of HyA with C18 groups effectively enhanced anchoring to the red blood cell surface. Therefore, the ald-hm-HyA/hm-ApGltn-based hemostatic agent has potential applications in cardiac surgery.