Fig. 1.

Illustration of modifying bacterial nanocellulose (BC) samples using organosilanes: 3-aminopropyltriethoxysilane (APTES) and octadecyltrichlorosilane (OTS), and the resulting idealized self-assembled monolayer on their surfaces. (A) BC samples were prepared by ambient-air drying for 48 h or freeze drying for 24 h. A surface of dried BC having abundant of hydroxyl groups was illustrated. (B) The BC surface was in contact with a thin layer (∼ 0.1 mm) of 1 wt.% organosilane/hexane solution on polystyrene Petri dish for 30 sec. Self-assembly of organosilane molecules formed by chemisorbing active head groups at the surface of BC. Loosely adsorbed molecules of organosilanes were removed by contacting the BC surface with a thin layer of silane-free hexane. (C) Organosilane-modified BCs (APTES- and OTS-modified BCs) were then dried with a stream of nitrogen gas, and annealed at 65 °C for an hour. Amine- and methyl-terminated BCs were ready for further characterizations.