3D-printed biopolymer matrices for the vehiculization and controlled release of octenidine in wound antibiotic therapy

Chronic and acute wounds are important health system problems due to re-hospitalization rates and treatment engagement. Antibiotic-controlled release systems can be a relevant solution for generating long-term therapies without patient intervention. The present work investigated pH-sensitive biopolymeric systems obtained by extrusion-based 3D printing. Alginate and carboxymethyl chitosan were used as matrix polymers for ink production, while octenidine was the vehiculized antibiotic. Different polymer proportions were explored to evaluate the release mechanism in response to different pH environments. Physicochemical characterization was performed using infrared spectrometry (FTIR) and thermogravimetric analysis (TGA). Detailed photography was used to determine 3D-printing fidelity. SEM images were used for the morphological characterization. Swelling and octenidine release profiles were evaluated in different non-chelating buffers. After the print's crosslinking bath, the obtained encapsulation efficiency was 100 %. The printing fidelity was in the order of 0.9–1.8. Swelling studies showed that some formulations lost weight, whereas others increased by 400 %. After 7 days, the drug released was 20–85 %, depending on the polymer composition and buffer/pH environment. All the prints presented antimicrobial capacity against Staphylococcus aureus. The present work demonstrates the potential of biopolymeric 3D-printed systems as advanced wound dressings, combining pH-responsive antibiotic release and antimicrobial activity with the adaptive design capabilities of 3D printing, offering a versatile platform for personalized wound-healing therapies.