Breakthrough Brain Microsystem Tracks Neural Activity and Dopamine in Real Time

Researchers from the Aerospace Information Research Institute at the Chinese Academy of Sciences have created a dual-mode wireless microsystem. It can monitor both electrophysiological activity and dopamine-related signals in the brain at the same time. This addresses a longstanding technical challenge in neuroscience. The microsystem combines a hybrid acquisition setup with a custom electrophysiological chip and an AD5941 electrochemical front end. A dual-controller design allows independent but synchronised data capture and wireless transmission. Its 32 high-sampling-rate channels track electrical activity, while electrochemical pathways detect dopamine fluctuations within the same compact device.

To enhance performance, the system uses reduced graphene oxide and Nafion for improved electrochemical sensitivity and selectivity. Platinum nanoparticles and PEDOT:PSS further boost conductivity and stability in recordings. In vitro tests confirmed its sensitivity, selectivity, and reliable wireless transmission over distances of up to 25 metres.

In vivo trials with rats demonstrated the microsystem’s ability to capture complex neural patterns linked to sedation. It recorded electrophysiological data and dopamine changes simultaneously, validating its dual-mode function. The research team includes Peiyao Jiao, Yilin Song, Jin Shan, Yu Liu, Qianli Jia, Qi Li, Ying Wang, Yan Luo, Pengfei Zhao, Juntao Liu, Zhenchang Wang, Mixia Wang, and Xinxia Cai. The team plans to refine the system by embedding custom integrated circuits for miniaturisation. Future versions may include multimodal closed-loop control and the ability to record from multiple brain regions at once. These advancements could expand its use in neuroscience research and clinical applications.