FRENCH POLYNESIA - SOCIETY ARCHIPELAGO - MAY 09: A diver checks the coral reefs of the Society Islands in French Polynesia. on May 9, 2019 in Moorea, French Polynesia. Major bleaching is currently occurring on the coral reefs of the Society Islands in French Polynesia. The marine biologist teams of CRIOBE (Centre for Island Research and Environmental Observatory) are specialists in the study of coral ecosystems. They are currently working on “resilient corals”, The teams of PhD Laetitia Hédouin identify, mark and perform genetic analysis of corals, which are not impacted by thermal stress. They then produce coral cuttings which are grown in a “coral nursery” and compared to other colonies studying the resilience capacity of coral. (Photo by Alexis Rosenfeld/Getty Images).
San Diego, California – Researchers at UC San Diego have developed an innovative material that could transform the future of coral reef restoration by making degraded reefs more appealing to coral larvae. The new gel, dubbed SNAP-X, releases chemical cues that significantly increase coral larvae settlement—a major challenge in reef recovery efforts.
The research, published Wednesday in Trends in Biotechnology, was led by scientists from UCSD’s Scripps Institution of Oceanography and Jacobs School of Engineering. SNAP-X mimics the chemical signals released by healthy reef environments, signaling to coral larvae that a surface is safe and suitable for attachment. In laboratory experiments, the gel increased coral larvae settlement by up to 20 times compared to untreated surfaces.
“Corals are animals, and their larvae are selective about where they settle because once they attach, they’re fixed there for life,” said senior author Daniel Wangpraseurt, a marine biologist at Scripps. “With SNAP-X, we created a material that releases chemical cues that tell coral larvae, ‘this is a good place to live.’”
Coral reefs are in peril worldwide due to ocean warming driven by climate change. Scientists estimate that 70-90% of reefs will disappear if temperatures rise 1.5°C above preindustrial levels. That number jumps to 99% if warming reaches 2°C.
Wangpraseurt’s lab—known for blending marine biology with nanotechnology—is working to develop practical, scalable solutions. “I’m over hearing that corals are dying—I want to know what we can do about it,” he said.
SNAP-X is made from silica-based nanoparticles that encapsulate compounds derived from crustose coralline algae, organisms known to attract coral larvae. The gel, which solidifies under UV light, can be painted or sprayed onto surfaces and releases chemical cues for up to a month—enough time to coincide with natural coral spawning events.
“Coral larvae use smell to find a healthy reef,” explained Samapti Kundu, the study’s first author. “But in degraded environments, those chemical signals are often absent. SNAP-X offers a controlled, slow-release delivery of the cues they’re looking for.”
The research was supported by the Defense Advanced Research Projects Agency’s (DARPA) Reefense program, which funds efforts to build self-healing reef structures for coastal protection.
While tests so far have focused on the Hawaiian coral Montipora capitata, the team believes SNAP-X can be adapted for other species using local algae compounds. Wangpraseurt and Kundu are working to commercialize the gel through a startup, Hybrid Reef Solutions, with support from UCSD’s Office of Innovation.
“This breakthrough shows what’s possible when you merge biology, nanotech, and engineering,” Wangpraseurt said. “We’re hopeful it can be a real game-changer for coral conservation.”
