Tannic acid/Ca ^II Anchored on the Surface of Chitin Nanofiber Sponge by Layer-By-Layer Deposition: Integrating Effective Antibacterial and Hemostatic Performance

Massive blood loss and bacterial infection are major challenges for global public health. However, traditional wound dressings cannot fully meet the current clinical needs in controlling bleeding and avoiding infection. In this study, we prepared a chitin nanofiber suspension by green mechanical grinding and homogenizing, which could be used for developing a porous chitin nanofiber sponge by freeze drying. Then tannic acid/Ca^II was anchored on the surface of chitin nanofiber sponge by layer-by-layer deposition based on the coordination complex of tannic acid and Ca²⁺. These porous chitin nanofiber sponges with meso-macroporous structure could accelerate platelet aggregation for hemostasis. Hemostasis tests also demonstrated that the Ca²⁺ and TA in the TA/Ca^II coating on chitin nanofiber sponge could accelerate platelet activity and shorten the hemostatic time both in vitro and in vivo. Besides, the TA in the TA/Ca^II coating enhanced the antibacterial properties of the sponge, which depended the content of TA/Ca^II. Based on these results, it could be inferred that the chitin nanofiber sponges anchored TA/Ca^II coating had rapid hemostatic and antibacterial properties, which would have great potential for designing hemostatic product in clinical application.

Keywords: Antibacterial; Chitin nanofiber; Hemostasis; Porous sponge; Tannic acid.