3D printed alginate-cellulose nanofibers based patches for local curcumin administration

[Display omitted] •Bioink formulations based on alginate and CNF (cellulose nanofibers) were developed.•Suitable alginate-CNF formulations were successfully 3D printed showing shape fidelity.•Freeze-dried scaffolds presented CNF modulated porosity and stiffness.•Curcumin was successfully stabilized in the bioinks, and loaded patches were 3D printed.•Curcumin release kinetics showed dependence on both CNF content and scaffold disintegration. Alginate and nanocellulose are potential biomaterials to be employed as bioinks for three-dimensional (3D) printing. Alginate-cellulose nanofibers (A-CNF) formulations with CNF amounts up to 5 wt% were developed and rheologically characterized to evaluate their printability. Results showed that formulations with less than 3 wt% CNF did not present suitable characteristics to ensure shape fidelity after printing. Selected A-CNF bioinks were 3D printed and freeze-dried to obtain porous scaffolds. Morphological and mechanical analysis were performed, showing that CNF contributed to the reinforcement of the scaffolds and modulated their porosity. The applicability for drug delivery was evaluated by the addition of curcumin to printable A-CNF formulations. The curcumin loaded bioinks were successfully 3D printed in patches and the in vitro release tests showed that alginate and CNF played an important role in curcumin stabilization, whereas the CNF content and the disintegration of the scaffold were essential in the release kinetics.