title: Bilayer hydrogel actuators with tight interfacial adhesion fully constructed from natural polysaccharides.
abstract: Smart hydrogel actuators with excellent biocompatibility and biodegradation are extremely desired for biomedical applications. Herein, we have constructed bio-hydrogel actuators inspired by the bilayer structures of plant organs from chitosan and cellulose/carboxymethylcellulose (CMC) solution in an alkali/urea aqueous system containing epichlorohydrin (ECH) as a crosslinker, and demonstrated tight adhesion between two layers through strong electrostatic attraction and chemical crosslinking. The bilayer hydrogels with excellent mechanical properties could carry out rapid, reversible, and repeated self-rolling deformation actuated by pH-triggered swelling/deswelling, and transformed into rings, tubules, and flower-, helix-, bamboo-, and wave-like shapes by effectively designing the geometric shape and size. The significant difference in the swelling behavior between the positively charged chitosan and the negatively charged cellulose/CMC layers generated enough force to actuate the performance of the hydrogels as soft grippers, smart encapsulators, and bioinspired lenses, showing potential applications in a wide range of fields including biomedicine, biomimetic machines, etc.
authors.affiliation: College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China. zhangln@whu.edu.cn.
authors.forename: Jiangjiang
authors.initials: J
authors.lastname: Duan
authors.affiliation: College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China. zhangln@whu.edu.cn.
authors.forename: Xichao
authors.initials: X
authors.lastname: Liang
authors.affiliation: College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China. zhangln@whu.edu.cn.
authors.forename: Kunkun
authors.initials: K
authors.lastname: Zhu
authors.affiliation: College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China. zhangln@whu.edu.cn.
authors.forename: Jinhua
authors.initials: J
authors.lastname: Guo
authors.affiliation: College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China. zhangln@whu.edu.cn.
authors.forename: Lina
authors.initials: L
authors.lastname: Zhang