On-Body 3D Printing EEG Tattoo

On-scalp digital printing of custom-designed, temporary-tattoo-like sensors marks a significant advancement in non-invasive brain monitoring. This approach overcomes the limitations of traditional EEG systems by combining material innovations with non-contact, on-body digital printing to fabricate e-tattoos that are self-drying, ultrathin, and compatible with hairy scalps. Using individual 3D head scans, custom sensor layouts, and a 5-axis microjet printing robot, these EEG e-tattoos offer precise placement and ensure high signal fidelity over extended periods. This technology paves the way for non-invasive, high-performance, and user-friendly brain monitoring that will enhance patient care, neuroscience, and the development of brain-computer interfaces (BCIs).

• Achieved low skin-contact impedance and stable signal collection.
• Ensured high signal fidelity and minimal skin irritation over extended wear (6+ hours).
• Successfully recorded high-quality multichannel EEG data, including alpha rhythms and event-related potentials.
• Developed a user-friendly method that eliminates the need for conductive gels and cumbersome cables.

We employed 3D scalp scanning to design personalized electrode layouts, followed by a direct-write microjet printing process using a 5-axis robot. Biocompatible conductive inks with slightly different compositions were used for electrodes and interconnects to achieve low skin contact impedance and high bulk conductivity, respectively. The system was validated through multichannel EEG acquisition on human participants.