Intelligent hydrogel with both redox and thermo-response based on cellulose nanofiber for controlled drug delivery

The purpose of this study is to develop a hydrogel with temperature and redox response to control drug delivery. However, the strength of temperature sensitive N-isopropylacrylamide (NIPAM) hydrogel is weak. Therefore, 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) oxidized cellulose nanofiber (CNF) is introduced to improve this problem. The compressive strength of hydrogels increased by 360% after CNF addition. Meanwhile, N,N '-bis (acryloyl)cystamine (BACy) is introduced into the hydrogels as a cross-linker, imparting redox responsive properties to the hydrogels. Tumor therapeutic drugs are used as model drugs for in vitro release studies. The drug release rate of hydrogel is regulated by temperature and reducing environment. The maximum cumulative release rate of doxorubicin (DOX) is 39.56%, and the Berberine (BBR) is 99.50% after 60 h. The swelling and transparency of hydrogels showed dramatic changes in the range of 30-40 degrees C. Cytotoxicity experiments demonstrated that the hydrogel had almost no cytotoxicity.

Automated summary

The purpose of this study is to develop a hydrogel with temperature and redox response for controlling drug delivery. By introducing TEMPO-oxidized cellulose nanofiber (CNF), the strength of the hydrogel was significantly improved. Furthermore, the hydrogel exhibited redox-responsive properties by adding N,N'-bis(acryloyl)cystamine (BACy) as a cross-linker. The drug release rate of the hydrogel was regulated by temperature and reducing environment, showing effective control. The hydrogel demonstrated excellent biocompatibility.