Hydrogels are water-swollen natural and synthetic polymer networks which mimic the extracellular matrix of biological tissues. Due to their high water content (>90% by mass), hydrogels uptake their surrounding medium, such as ions, small molecules, and dissolved oxygen in biological fluids (e.g. cell culture media, interstitial fluid). Beyond ionic conductivity, hydrogels may be engineered to possess functional properties such as electrical, magnetic, optical, and piezoelectric. For example, hydrogels may be made of intrinsically electronically conducting polymers, such as conjugated polymers and mixtures based on thiophenes, pyrroles, or anilines. Additionally, active additives (e.g. polymers, nanomaterials, drugs) can be embedded in the matrices to impart other properties. Such functional hydrogels are being explored as part of bioelectronic, ionotronic, and photonic devices. In addition to functional properties, hydrogels may be designed to have unique mechanical properties that outperform their non-hydrogel counterparts. Soft hydrogels with mechanical profiles comparable to biological tissues may be ideal for biointerfacing, or formulations with high toughness or self-healing properties may useful in strain-dynamic applications. Despite these successful demonstrations, the synthesis and processing to achieve mutually exclusive properties, such as high conductivity with high stretchability, remains challenging. In various applications, hydrogels and their assembled devices are required to perform in complex environments, which imposes additional constraints on fundamental materials properties.

This symposium will bring together investigators from multiple disciplines to address the synthesis, characterization, processing, and fabrication of hydrogels or other hydrated materials that either (1) possess advanced properties including electronic, ionic, magnetic, optical, and piezoelectric or (2) are used in the construction of functional devices, such as electrode arrays, sensors, wearables for biological interfacing; biomimetic devices; soft robotics, and actuators; devices for monitoring and controlling cellular systems in vitro.

additive manufacturing biological biomaterial organic