Reconstruction of Chitosan Network Orders Using the Meniscus Splitting Method for Designing pH-Responsive Materials

Area of Science:

• Materials Science
• Polymer Chemistry
• Biomaterials

Background:

• Chitosan, derived from chitin, is a biocompatible polymer with potential as a sustainable alternative to synthetic plastics.
• While chitosan's microstructures are understood, creating millimeter-scale anisotropic materials remains a challenge.

Purpose of the Study:

• To develop a method for creating millimeter-scale chitosan materials with ordered microstructures.
• To investigate the anisotropic pH-responsive properties of the fabricated chitosan membranes.

Main Methods:

• Utilized the meniscus splitting method to reconstruct a chitosan network from an aqueous solution.
• Formed chitosan membranes via ordered deposition driven by capillary forces during controlled evaporation between two air-liquid interfaces.

Main Results:

• Successfully created millimeter-scale chitosan membranes with three-dimensionally ordered microstructures and microlayers.
• Demonstrated directional swelling in aqueous environments and reversible/irreversible swelling-deswelling behavior controlled by pH.

Conclusions:

• The meniscus splitting method enables the fabrication of anisotropic chitosan hydrogels with tunable pH responsiveness.
• These chitosan materials show promise for applications under physiological conditions as next-generation functional materials.