Characterization of antibacterial aerogel based on ɛ-poly-l-lysine/nanocellulose by using citric acid as crosslinker

In this paper, based on the TEMPO oxidated Cellulose Nanofiber (TOCNF)/ɛ-poly-l-lysine (ɛ-PL) cross-linking network and citric acid as the cross-linking agent, aerogel material was designed. Citric acid (CA) can be used as a multifunctional cross-linking agent with TOCNF esterification cross-linking, and with TOCNF and ɛ-PL hydrogen bond cross-linking, but also as a reinforcing agent to improve mechanical and antibacterial properties. When the ɛ-PL content reached 0.8%, the tensile strength of the aerogel increased from 12.03 MPa to 26.44 MPa, while the elongation at break decreased to 29.33%. As the amount of ɛ-PL increased, the thermal decomposition temperature of aerogel rose to 215 °C. Aerogels had a high antibacterial efficiency (above 99.9%). After 28 days, aerogels can be biodegraded in the soil. More importantly, the aerogel had a hemolysis rate of less than 5%, indicating that the prepared degradable cellulose aerogel was a material with good blood compatibility. It had huge application potential in medical environment and food packaging.