| 초록 |
One of the most critical drawbacks of chitosan as a biomedical material is its poor mechanical properties in wet conditions. We designed a method to improve the mechanical properties of chitosan in wet conditions and minimized the swelling behavior of chitosan films in water by mimicking the sclerotization of insect cuticles and squid beaks, i.e., catechol-meditated cross-linking. The biomimetic composite film was prepared by mixing chitosan with DOPA as a catecholic cross-linker and sodium periodate as an oxidant. DOPA-meditated cross-linking on the chitosan film was indirectly verified via thermodynamic evidence, i.e., Tg data and solubility in acetic acid values. The formation of hydrophobic melanin was verified using UV-Vis spectroscopy and XPS. The cross-linking and the formation of the melanin compound provided a 7-fold enhancement in stiffness in wet conditions compared to pure chitosan films and reduced the swelling behavior of the chitosan film due to water adsorption. |
