Cellulose Nanofibril/polylysine-Based 3D Composite Antibacterial Scaffold for Wound Healing Applications

Bacterial infections are the major inhibitory factors for natural wound healing. 3D bioprinted nanocellulose-based composite scaffold with a desirable porous and shape specificity is highly effective for antibacterial applications. However, the slow self-healing and lack of antibacterial activities of cellulose cause bacterial infection. In this work, Epsilon-poly-L-lysine (EPL) bioconjugated cellulose nanofibrils (TCNFs) were subjected to bioprinting with a customizable 3D scaffold with biocompatible and antibacterial activities. Results show that the 3D composite scaffold possesses a mesoporous structure (2–50 nm) and high specific surface area (232.25 m2/g) that ensure a high adsorption capacity of red blood cells in wound healing. The in vitro cytocompatibility of the scaffold is confirmed by the growth and proliferation of NIH 3T3 fibroblast cells in a 3D cell culture study. In addition, the 3D composite scaffold shows antimicrobial activity against wound-infecting pathogens, namely Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria. In summary, this work integrates the uniqueness of 3D bioprinting and the inherent characteristics of TCNF/EPL-based composite into a flexible 3D scaffold to achieve antibacterial performance and cytocompatibility for biomedical applications.