Recently

chitosan nanoparticles have been an attractive biomaterial for their unique properties. Chitosan nanoparticles are mainly used as drug delivers. However

they are seldom used in wound healing after severe bleeding. In the present paper

chitosan nanoparticles with an average size of 60.2 nm were prepared through ionic gelation and characterized by X-ray diffraction and FT-infrared spectrometry. A new animal model of severe bleeding was made to evaluate its effects on wound healing besides hemostasis. The results showed that it can achieve well hemostatic effects and also induce wound healing after severe bleeding. Blood cells can be absorbed by chitosan nanoparticles and the bleeding is treated. Furthermore

the chitosan nanoparticles sustains longer than other materials in wound healing. At the 15th day after operation

the chitosan nanoparticles with the size of 58.3 nm can still be seen in the new-regenerated hepatic tissue. It can induce the formation of a clear granulation around the wound site. Through histological observation

we find out that chitosan-TPP nanoparticles can induce wound healing through migration of the inflammatory cells and synthesis of collagen. So

chitosan nanoparticles show us both hemostasis and the ability of wound healing for parenchymal organs.