Bioactive carbon dots as antibacterial neural interface for neuron recording

Neural electrodes are critical components for recording and stimulating neural signals in neuroscience and clinical applications. Despite their widespread adoption in clinical practice, current technology continues to face limitations in signal sensitivity and biocompatibility. Herein, antibacterial neural electrodes functionalized with carbon dots (CDs) are developed, whose nanostructured surfaces and rich oxygen-containing functional groups facilitate rapid charge transfer and interfacial compatibility. The CDs electrodes reduced impedance by 64.6% compared to bare electrodes (160.14 ± 6.81 vs. 451.9 ± 13.9 MΩ·μm 2 ) and enhanced cathodic charge storage capacity by 5.4-fold, while maintaining excellent interfacial stability. The CDs electrodes achieve 99.2% microbial inhibition within 1 h and mitigate oxidative stress through enzyme-mimicking decomposition of reactive oxygen species, thereby reducing implant-associated infection risk. In vivo neural recordings in rats revealed a 2.5-fold increase in oscillation amplitude and a 2.13-fold enhancement in signal-to-noise ratio, thereby validating the improvement in bioelectric sensitivity. This study developed a CDs-modified neural interface that combines anti-infection properties with enhanced bioelectric performance, offering a promising strategy to improve biosafety in the precise diagnosis and treatment of neurological disorders. • CDs electrodes enhance detection sensitivity via rapid charge transfer. • Enabling 64.6% impedance reduction and 5.4-fold enhanced CSCc through CDs modification. • 95% infection inhibition via bacterial membrane rupture by positive surface charges. • Enzyme-mimicking CDs scavenge ROS to combat oxidative stress.