Single‐Step Patterning of Biocompatible Neural Electrodes Using Black‐Pt Functionalized Laser‐Induced Graphene for in Vivo Electrophysiology

Neural electrodes are essential tools for monitoring electrophysiological activity in the brain, driving advances in neuroscience and neurotechnology. However, conventional semiconductor-based fabrication techniques suffer from high costs, complex procedures, and limited adaptability for customized designs. Here, a single-step patterning, scalable method is presented for fabricating biocompatible neural electrodes using laser-induced graphene (LIG) patterned directly onto polyimide substrates. This process requires only a standard CO₂ laser system, a spray-coated biocompatible lubricant, and black-Platinum (Pt) functionalization to form conductive traces, electrode sites, and connector pads-eliminating the need for cleanroom infrastructure or photolithography. Selective laser ablation enables precise electrode exposure, allowing rapid prototyping across various formats, including electroencephalography (EEG), electrocorticography (ECoG), and penetrating neural probes. The entire fabrication process is completed within 5 h, reducing production time and cost by over two orders of magnitude compared to conventional approaches. Demonstrating mechanical robustness, reliable signal acquisition, and biocompatibility, the fabricated electrodes exhibit high fidelity in recording EEG, ECoG, and spike signals in anesthetized mice. These findings underscore the method's strong potential for rapid prototyping of personalized brain-computer interfaces, neurological monitoring systems, and scalable preclinical research tools.