Biocompatible smart dual-responsive cellulose nanofibres were designed and prepared by grafting a temperature and pH dual-responsive polymer (PEI-NIPAM: polyethyleneimine–N-isopropylacrylamide) on cellulose nanofibres (CNF-COOH). The smart cellulose nanofibres showed good antibacterial activity (above 99%) against Escherichia coli and excellent biocompatibility based on acute systemic toxicity, in vitro cytotoxicity, skin irritation, and skin sensitisation analyses. CNF-PEI-NIPAM showed an excellent dual-response performance to pH and temperature, affording the CNF-PEI-NIPAM aerogel with a high loading capacity (330.12 mg/g) for doxorubicin and a high cumulative release rate (59.45 %) at 37 °C and pH 3. These advantages enable the smart cellulose nanofibres to be applied in the fields of food and biomedicine. Interestingly, the interaction between the collapse and expansion of the dual-responsive polymer molecular chains on the CNF-COOH was revealed based on in situ characterisation of the solid materials, which is valuable for the structural design and application of cellulose-based dual-responsive smart nanofibres.

通过将温度和pH双响应聚合物（PEI-NIPAM：聚乙烯亚胺-N-异丙基丙烯酰胺）接枝到纤维素纳米纤维（CNF-COOH）上，设计和制备具有生物相容性的智能双响应纤维素纳米纤维。智能纤维素纳米纤维对大肠杆菌表现出良好的抗菌活性（99％以上）基于急性全身毒性，体外细胞毒性，皮肤刺激性和皮肤致敏性分析的优异生物相容性。CNF-PEI-NIPAM对pH和温度具有出色的双重响应性能，从而使CNF-PEI-NIPAM气凝胶对阿霉素的负载量高（330.12 mg / g），在37℃时具有高累积释放率（59.45％） °C和pH 3.这些优点使智能纤维素纳米纤维可用于食品和生物医学领域。有趣的是，基于固体材料的原位表征，揭示了CNF-COOH上双响应聚合物分子链的塌缩与扩展之间的相互作用，这对于基于纤维素的双响应聚合物的结构设计和应用非常有价值。智能纳米纤维。