NCCR Bio-Inspired Materials researchers have developed a breakthrough method using light-based 3D printing, known as Digital Light Processing (DLP), to create "living" materials that glow in response to touch or movement.

Tiny marine algae known as dinoflagellates (Pyrocystis lunula) naturally convert mechanical stress into flashes of blue light, a process called mechanoluminescence. NCCR PI André Studart and his colleagues embedded the algae into biocompatible hydrogels and, using DLP, printed them into intricate, complex geometries. These include sponge-like "gyroid" structures and porous robotic finger caps, overcoming previous hurdles to incorporating the marine organisms via other methods.

A key advantage of these 3D-printed living gels is their ability to act as autonomous material systems; they function as a biological "band-pass filter," meaning they only glow when a specific threshold of force or speed is reached. Background noise is effectively ignored.

This allows the material to process information and respond to its environment locally, much like the distributed sensing found in octopus arms and the Venus flytrap, and reduces the need for complex electronics or heavy batteries.

According to the researchers, the combined metabolic activity of the dinoflagellates and the creative freedom of 3D printing offer an enticing approach to designing and fabricating mechanoluminescent living materials for optics-based mechanosensing, signaling, illumination, and soft robotics applications.

Robots could, for example, visualize their own movements or signal neighbors without a physical connection. Tactile sensing would be another application in which printed pillars act as "living sensors" for prosthetic fingertips, providing real-time light feedback during delicate tasks. Finally, as optical transducers - a device that converts energy into a light signal - these gels could efficiently turn physical pressure into high-speed light signals for communication in dark environments.

Reference: Light-based 3D printing of mechanoluminescent living gels loaded with dinoflagellates, Sci. Adv., 2026 https://doi.org/10.1126/sciadv.adz0017