A Dual-Mode Wireless Microsystem for Monitoring Dopamine and Spike Changes with Dexmedetomidine

To understand how cortical circuits respond to pharmacological regulation, tools that can simultaneously detect electrophysiological and electrochemical signals in vivo are needed. However, most existing methods target only a single modality or depend on tethered recording systems that constrain movement and limit the ability to monitor coordinated neural processes. To address these challenges, we developed a dual-mode wireless microsystem that enables simultaneous recording of spikes, local field potentials (LFPs), and dopamine (DA)-related electrochemical signals on microelectrode arrays. The platform integrates a PtNPs/PEDOT:PSS/rGO/Nafion-modified electrochemical site for sensitive and selective detection of DA, as well as independent electrophysiological and electrochemical acquisition pathways that support stable long-distance wireless transmission of dual-mode signals. In vitro tests demonstrated that the platform can stably detect DA within a certain range and exhibits reliable wireless transmission performance. Using this platform, we recorded simultaneous electrophysiological and dopaminergic signals from the prelimbic cortex under different doses of dexmedetomidine. The results showed that increasing drug dose led to a significant reduction in spike firing rate and high-frequency LFP power, accompanied by dose-dependent elevations in DA-related amperometric response. These combined measurements showed simultaneous dose-dependent changes in electrophysiological activity and the DA-related electrochemical signal under dexmedetomidine. This dual-mode wireless microsystem provides a practical tool for neuroscience experiments requiring the integration of electrophysiology and neurochemistry.