Bimetallic nanoparticles mediated plasmonic enhanced cardiac electrophysiology by cell based excitation biosensor.

Bradyarrhythmia is a life-threatening cardiac disease due to its intricate pathophysiology and limited therapeutic options. Conventional clinical approaches, including pharmacotherapy and pacemaker implantation, are limited by drug resistance, surgical complications, and the absence of real-time treatment evaluation capabilities. To overcome these challenges, we develop an integrated biosensing-regulating platform capable of simultaneous in situ NIR-II photothermal treatment and electrophysiological signal recording. The platform employs branched Au/Ag bimetallic nanoparticles (NPs) as photothermal agents, which exhibit superior localized surface plasmon resonance effects compared with spherical monometallic counterparts. Under NIR-II laser irradiation, Au/Ag NP-mediated photothermal regulation can effectively treat cardiomyocyte-based bradyarrhythmia. By regulating the molar ratio of bimetallic components and irradiation duration, we achieve the precise control through plasmonic photothermal effects, which can maintain the restored normal rhythm for a long time. This work proposes a promising plasmonic photoregulation strategy for cardiomyocyte-based bradyarrhythmia treatment and provides a potential platform for related cardiac disease research and diagnosis.