Subsense is developing a nanoparticle-based non-surgical brain-computer interface delivered via nasal spray. The company emerged from stealth in February 2025 with a $17M seed round, followed by a $10M extension in December 2025. Subsense's approach uses engineered nanoparticles that cross the blood-brain barrier and self-assemble into neural recording networks, enabling high-resolution brain signal capture without any surgical procedure. The company collaborates with UC Santa Cruz and ETH Zurich.