Boron nitride embedded in chitosan hydrogel as a hydrophobic, promising metal-free, sustainable antibacterial material

Evaporation-induced co-assembly of boron nitride-exfoliated chitosan hydrogel provides micrometer-thick boron nitride-filled chitosan nanocomposite films. Owing to the favorable interfacial interaction of NH2 belonging to chitosan and boron center in boron nitride (BN) sheets, a loading of up to 60 wt% of boron nitride could be entrapped inside, without compromising the film quality or its flexibility. Notably, increasing boron nitride loading alters the wettability of the resulting films and improves its mechanical and thermal properties. Enhanced biological response (e.g., antibacterial properties) also correlates with the entrapped amount of boron nitride, which highlights the potential use of the latter as metal-free, antibacterial surface coating materials. Evaporation-induced co-assembly of boron nitride-exfoliated chitosan hydrogel provides micrometer-thick boron nitride-filled chitosan nanocomposite films.