Spatially Programmable Electroadhesive Enables In Situ Site-Selective Functional Coupling.

Abstract

Precise intraoperative integration of bioelectronic devices with wet tissue surfaces remains a challenge due to the limited spatial control of adhesion sites. Here, an in situ spatially programmable electrical bioadhesive (termed "STICH") is reported that enables site-selective adhesion and functional coupling via light-activated bonding with wet biological tissue. Upon irradiation with patterned green light, Rose Bengal in a chitosan/silver nanowire hydrogel matrix generates singlet oxygen, which oxidizes amino acid residues into carbonyl groups on the tissue surface. The covalent bonding is then formed between the newly formed reactive carbonyl group and amine groups on chitosan. The spatially programmable adhesive allows robust tissue bonding with a lap-shear strength of 160 kPa and precise adhesion regions at ≈2 µm resolution. The light-patternable adhesive enables spatially resolved mechanical coupling for directional electromechanical sensing on ex vivo cardiac tissue. The low impedance adhesive interface also provides spatially programmed electrical coupling for in vivo neuromuscular stimulation on intraoperatively selected muscle groups. This platform advances microscale device-tissue integration and paves the way for reconfigurable bioelectronic therapies.