An All-in-One Implantable Flexible Probe with Integrated Self-Referencing Electrode for Neural Recording, Electric Stimulation, and In-Situ pH Sensing

This paper reports a novel integrated self-referencing electrode all-in-one implantable flexible probe (SAIFP), realizing neural recording, electric stimulation, and in-situ pH sensing. SAIFP has 128 recording electrodes (REs) and 4 runway-shaped electrodes (RsEs), both of which have been modified with iridium oxide (IrOx). Meanwhile, a self-referencing electrode (Sref) is integrated into SAIFP by electroplating with Ag/AgCl. RsEs are utilized in conjunction with Sref to facilitate in-situ pH detection, and concurrently, RsEs fulfill the dual purpose of stimulating electrodes (STs), enabling targeted electric stimulation. In short, the SAIFP, capable of actualizing more functions within a limited implantation area, further advances the study of the operational mechanisms of the brain.