Researchers have engineered a novel dynamic chitosan hydrogel that senses environmental changes and redefines the boundaries of 3D printing. (Nanowerk News) In the world of advanced materials, the ultimate goal is to create a substance that possesses the adaptability of biological tissue: it must be strong enough to maintain its shape, yet fluid enough to be molded. The research team at National Taiwan University (NTU) has achieved this balance by developing a sophisticated "CGB" hydrogel system, with their findings recently published in the journal Carbohydrate Polymers ("Glucose-sensitive and 3D-printable dynamic chitosan hydrogels from boronic acid-functionalized chitosan and gallol-functionalized chitosan"). This study, led by Professor Shan-hui Hsu, introduces a dual-component system: gallol-functionalized chitosan (CG) and boronic acid-functionalized chitosan (CB). When these two bio-based polymers meet, they establish "dynamic covalent bonds"—a molecular handshake capable of breaking and reforming at will. Precision in biofabrication "Our material can be extruded through a tiny 160 μm nozzle and stably stacked up to 60 layers without collapsing," the team notes. "Achieving such structural stability at a solid content of only 2 wt% represents a major leap in biofabrication, as it provides a more biocompatible environment for embedded cells." The intelligent architect of microchannels Beyond its strength, the CGB hydrogel is a "smart" material that responds to chemical signals such as glucose and redox changes. The team demonstrated the versatility of this hydrogel as a "sacrificial material," successfully fabricating intricate, hierarchical microfluidic channels—including complex 90°-rotated H-shaped architectures. By printing the CGB hydrogel as a temporary mold and subsequently dissolving it with a glucose solution, researchers can create delicate hollow structures mimicking natural biological plumbing. A bioactive future “With potent antimicrobial activity and over 90% cell viability, the CGB hydrogel is more than just an ink; it is a bioactive platform. This research provides scientists with a powerful tool, allowing the future of regenerative medicine to become a reality through 3D printing, one layer at a time,” says corresponding author Shan-hui Hsu, Ph.D., distinguished professor of polymer science and engineering at National Taiwan University.
Source: National Taiwan University (Note: Content may be edited for style and length)