Self-Healing, Ultra Stretchable, Antifreezing, and Antidrying Gelatin-Based Eutectogels Containing Polymerizable Deep Eutectic Solvent for Advanced Motion Sensing

Abstract

In recent years, with the advancement of technology and electronics, there has been an increasing interest in small, flexible, and wearable electronic devices. These flexible devices have been significantly used in various aspects of our lives, such as health monitoring, wearable devices, smart robots, and artificial intelligence. In this study, a superelastic, strong, and transparent eutectogel based on glycidyl methacrylate-modified gelatin (GelGM) and a conductive polymerizable deep eutectic solvent (PDES) composed of citric acid (CA) and dimethyl diallyl ammonium chloride in a 1:2 ratio was synthesized. The prepared eutectogel showed favorable transparency, excellent stretchability (1788.85%), high mechanical strength (0.25 MPa), good conductivity (13.75 mS.cm^–1), sensitivity (GF = 2.71), high stability (1000 cycles), self-healing ability, excellent adhesion to various substrates, biocompatibility, and good antibacterial properties. Also, unlike traditional hydrogels, with the addition of PDES, the fabricated sensor exhibited better resistance to freezing and drying, which confirms its wide temperature performance. Therefore, the prepared AGD eutectogel was able to maintain its performance well under different ambient temperature conditions. Also, the prepared wearable sensor showed good antibacterial performance against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria, protecting it from skin damage and infection. The prepared eutectogel with excellent adhesion, high adaptability to various surfaces due to its extraordinary flexibility, and high sensitivity was able to detect various body movements well. Also, by placing it on the volunteer’s larynx, it successfully recorded subtle movements such as speaking and swallowing. These outstanding features of eutectogel have made it an ideal and suitable option in various practical applications such as health monitoring, wound healing monitoring, recovery, rehabilitation, and use in wearable electronics.