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Updated: Jan 24, 2026
Scalable Syntheses of Graphene Oxide and Reduced Graphene Oxide using Cascade Design Oxidation and Highly Basic Reduction Reactions
Published on: July 3, 2025
N-alkylated chitosan/graphene oxide porous sponge for rapid and effective hemostasis in emergency situations
Ying Zhang1, Jing Guan2, Jimin Wu3
1Department of Polymer Science and Technology, Key Laboratory of Systems Bioengineering of the Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China; Institute of Medical Support Technology, Academy of Military Sciences, Tianjin, 300161, China.
Abstract:
N-alkylated chitosan (AC) sponges and graphene oxide (GO) sponges are promising candidates for emergency hemostat. However, AC sponges have weak mechanical strength and GO sponges may induce toxicity. To overcome these problems, a series of AC/GO composite spongs (ACGS) were prepared with various ratios (GO/AC, 0%, 5%, 10%, and 20%) using a dilute solution freeze phase separation and drying process. The sponges exhibit excellent absorption capacity, mechanical stability, and biocompatibility. In serial in vitro clotting tests, the higher the ratio of GO, the better the coagulation efficiency. ACGS with 20% ratio of GO (ACGS20) has shorter hemostatic time than Celox in a rabbit femoral injury test. Moreover, ACGS20 can accelerate erythrocyte and platelet adhesion. CD62p and intracellular Ca2+ measurements show that ACGS20 can promote the release of intracellular Ca2+ and stimulate platelet activation. These results suggest that ACGS20 is a good candidate composition for a safe and efficacious hemostatic dressing.
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