pH-responsive release features of collagen/carboxylated cellulose nanofiber composite aerogels through the incorporation of cyclodextrin/ 5-fluorouracil inclusion complexes

pH -responsive materials have great potential for use in various advanced fields, such as microreactors and drug delivery. This work proposes a promising strategy for preparing composite aerogels with pH -responsive properties based on collagen (COL) and TEMPO -oxidized cellulose nanofibers (CNFs) through the self -assembly behavior of COL molecules for controlled -drug release. COL fibrils and carboxylated CNFs (cCNFs) exhibited a high -density, physical cross -linked supramolecular double network structure. Specifically, cyclodextrins (CDs) were introduced to optimize the structural stability and slow -release capability of the composite aerogels. Scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and thermogravimetric analyses were used to characterize the structure of the aerogels, and the swelling behavior and water contact angle of the aerogels were evaluated. Using 5-fluorouracil (5 -FU) as the model drug, the slow -release mechanism was subsequently revealed. Compared with the COL aerogels and COL/cCNF composite aerogels, the COL/ cCNF@CD composite aerogels exhibited enhanced structural stability and slow -release performance through the synergistic enhancement effect of cCNFs and CDs. The aerogels also exhibited sensitivity to pH for regulating 5FU release, and the COL composite aerogels with CDs and cCNFs maintained excellent cytocompatibility. In conclusion, CDs had a positive effect on the structural stability and pH -responsiveness of the composite aerogels and promoted the possible utilization of aerogels in drug delivery systems.