Multifunctional Protein Eutectogels Based on Polyphenolic: Zwitterionic Low‐Transition‐Temperature Mixtures

Abstract Low‐transition‐temperature mixtures (LTTMs) are an exciting class of eutectic solvents that undergo a second‐order phase transition (i.e., a glass transition) rather than a typical melting point. Herein, an innovative soft eutectogel is presented incorporating therapeutic LTTMs based on a natural polyphenol and a renewable, non‐toxic, and biodegradable zwitterionic compound. This LTTM enables the formation of protein‐based elastomers with multiple functional properties, including strong adhesiveness, anti‐freezing and anti‐drying behavior, high elasticity, water resistance, and anti‐inflammatory activity. Notably, It is found that the high polyphenol content in the LTTM completely disrupts protein‐protein interactions, hindering the formation of secondary structures essential for gelation in water. Instead, water‐mediated protein‐polyphenol interactions promote the formation of tough physically crosslinked gels, with the zwitterion playing a key role in preventing excessive binding that would otherwise lead to protein precipitation. Furthermore, the presence of the polyphenol in a dynamic liquid state provides long‐lasting stickiness, which is exploited to microstructure the eutectogel surface via the breath figure technique, yielding bilayer functional materials. This study opens a new avenue for designing versatile soft materials from LTTMs, demonstrating how liquefying solid polyphenols can expand the application scope of many multifunctional building blocks.