Gelatin‐Based Functional Biogels With Mechanical Tunability via Pioneering Design of Co‐Polymerizable Deep Eutectic Solvents

ABSTRACT Eutectic biogels, combining deep eutectic solvents (DES) with biopolymer networks, are highly promising for advanced applications. However, the design of co‐polymerizable DES (cPDES) remains largely unexplored for novel biogels. Herein, we constructed an innovative cPDES by strategically selecting 2‐(acryloyloxy)ethyl trimethyl ammonium chloride as the polymerizable hydrogen bond acceptor and itaconic acid as the polymerizable hydrogen bond donor. By employing this cPDES as a functional solvent, gelatin as the matrix, and glycerol as a regulator, a multifunctional biogel (denoted as BioGel‐PGG) with a unique polymeric network integrating an enhanced non‐covalent network with a dual network induced by the copolymerization of DES was developed, which showed widely tunable mechanical properties (e.g., elastic modulus: 0.03–55.52 MPa, toughness: 0.05–14.03 MJ/m 3 ). Furthermore, BioGel‐PGG demonstrates multifunctionality integration, including strong skin adhesion (3.20 N/cm), good conductivity, environmental stability, recyclability, and biodegradability. Epidermal bioelectrodes based on BioGel‐PGG enabled high‐quality monitoring of electrophysiological signals. This work opens a new avenue for designing high‐performance eutectic biogels by exploiting cPDES.