A pH-responsive, injectable and self-healing chitosan-coumarin hydrogel based on Schiff base and hydrogen bonds

作者：Shi, Haolei; Ma, Dongxu; Wu, Di; Qiu, Xiao; Yang, Shuai; Wang, Yingying; Xiao, Lei; Ji, Xinyao; Zhang, Wei; Han, Shuaiyuan; Huo, Pengfei; Dong, Jidong^*; Kong, Xianzhi^*; Guan, Xue^*; Zhang, Dawei^*

来源：International Journal of Biological Macromolecules, 2024, 255: 128122.

DOI：10.1016/j.ijbiomac.2023.128122

• Chitosan-coumarin hydrogel
• Schiff base bond
• pH -responsiveness
• Injectability

Smart hydrogels have shown great potential applications in disease treatment due to their controlled and local drug-release ability. Herein, a smart hydrogel with pH-responsive, injectable, and self-healing properties for controlled release of taxifolin (TFL) was prepared by freezing-thawing and photo-crosslinking methods. The crosslinking network of hydrogels (CS-CA hydrogels) was constructed by the hydrogen bonds, Schiff base bonds, and cyclobutane rings using chitosan (CS) and coumarin (CA) as raw materials. The CS-CA hydrogel demon-strated a compressive strength of 1.04 MPa, a self-healing efficiency of 99.9 %, and could maintain structural and functional integrity after injection. In addition, the drug release rate and shape of the CS-CA hydrogels were tunable due to its pH sensitivity. The TFL cumulative release reached 60 % within 12 h at pH = 4, and after equilibration, the cumulative release of TFL at pH = 4 (80 %) was significantly higher than at pH = 9.2 (50 %). The CCK8 experiment showed that the resulting hydrogel had no cytotoxicity. Meanwhile, subcutaneous im-plantation experiments in mice showed that the CS-CA hydrogels had favorable biodegradability and compatibility.

• 单位
  哈尔滨医科大学; 东北林业大学