Drug loaded cellulose–chitosan aerogel microfibers for wound dressing applications

Cellulose and chitosan have been studied for wound dressing due to their biocompatibility, biodegradability, lower antigenicity, and renewability. The functional and structural characteristics of such biopolymers can be dramatically improved by their transformation into fibrous bioaerogels due to their outstanding characteristics such as low density, high porosity, and large specific surface area. Producing aerogels in the form of fibers and textiles not only can enhance mechanical properties, stiffness, and shapeability of aerogels but also lead to short drying times and scalable production processes. Hereby, wet spun chitosan-cellulose aerogel microfibers (CHCLAFs) in two ratios of 1:5 and 1:10 have been produced by supercritical CO 2 (scCO 2 ) drying for wound dressing application. The fibers were also loaded with ibuprofen (IBU) through post-treatment scCO 2 impregnation. CHCLAF characteristics in terms of morphology, textural properties, thermal stability, mechanical properties, and in vitro assessment such as drug release, antibacterial properties, cytotoxicity, and wound exudate uptake were analyzed and compared to pure cellulose aerogel microfibers (CLF). Blended CHCLAFs showed a low density (~ 0.18 g/cm 3 ), high porosity (~ 85%), and large specific surface area (~ 300 m 2 /g) with a macro-porous outer shell and a nano-porous inner core. The fibers were transformed into braided meshes that were highly water absorbable (~ 400 wt.%) and bactericidal against escherichia coli and staphylococcus aureus . Furthermore, the fibrous structures showed no cytotoxicity using fibroblast cells, and the hybrid fibers were able to release IBU over 48 h in a sustained manner. The results showed that the CHCLAFs could be used as a promising candidate for wound dressing materials. Graphical abstract