Mussel-Inspired Hydrogels for Self-Adhesive Bioelectronics

Wearable and implantable bioelectronics are receiving a great deal of attention because they offer huge promise in personalized healthcare. Currently available bioelectronics generally rely on external aids to form an attachment to the human body, which leads to unstable performance in practical applications. Self-adhesive bioelectronics are highly desirable for ameliorating these concerns by offering reliable and conformal contact with tissue, and stability and fidelity in the signal detection. However, achieving adequate and long-term self-adhesion to soft and wet biological tissues has been a daunting challenge. Recently, mussel-inspired hydrogels have emerged as promising candidates for the design of self-adhesive bioelectronics. In addition to self-adhesiveness, the mussel-inspired chemistry offers a unique pathway for integrating multiple functional properties to all-in-one bioelectronic devices, which have great implications for healthcare applications. In this report, the recent progress in the area of mussel-inspired self-adhesive bioelectronics is highlighted by specifically discussing: 1) adhesion mechanism of mussels, 2) mussel-inspired hydrogels with long-term and repeatable adhesion, 3) the recent advance in development of hydrogel bioelectronics by reconciling self-adhesiveness and additional properties including conductivity, toughness, transparency, self-healing, antibacterial properties, and tolerance to extreme environment, and 4) the challenges and prospects for the future design of the mussel-inspired self-adhesive bioelectronics.