Dry ionic conductive elastomers based on polymeric deep eutectic solvents for bioelectronics

Polymerizable deep eutectic solvents (PDESs), also known as deep eutectic monomers, have emerged as a versatile material platform for fabricating dry ionic conductive elastomers (ICEs). ICE materials present numerous opportunities for wearable sensors, bioelectrodes, and biomedical device integration. Recent advances have been pursued to expand the current PDES library, incorporating innovative building blocks with multifunctional properties and allowing new families of ionic polymers known as polyDES. In this review, we delve into the central features of PDES, highlighting its macromolecular engineering for tuning its properties and designing new ionic conductive elastomers based on polyDES, including copolymers, dynamic and double networks, or nanocomposites. In addition, additive manufacturing techniques for structuring these ionic polymers are also overviewed. Finally, the latest advances in their bioelectronic applications, as well as current demands and potential opportunities for future developments of PDES, are discussed. This review highlights the recent progress on polymerizable deep eutectic solvents (PDES) and polyDES as liquid-free ionic elastomers in bioelectronics and discusses future directions on how these functional polymers can expand the field.