Tangled Seaweed Inspires One-Size-Fits-All Cleaners for Ocean Microplastics

Researchers at NC State University have developed superadhesive meshes inspired by the way seaweed naturally tangles and traps debris in the ocean. The meshes capture microplastic particles across a wide size range, from millimeters down to tens of nanometers, something existing cleanup methods have struggled to do in a single system.

The material is built from alginate and chitosan, biopolymers derived from seaweed and crustacean shells. The structure works like a fluffy net: larger particles get physically caught in the mesh openings, while smaller particles stick to a branching nanofiber coating on the surface. Lead researcher Orlin Velev says the team wanted to mimic what tangled seaweed is already doing in the water. The meshes have been tested in both freshwater and saltwater, and spent material could potentially be processed through microbial digestion to break down captured plastics and recover the biopolymer for reuse.

For the seaweed sector, the relevance is double. Alginate is the feedstock, and the researchers flag that the raw materials are of natural origin and relatively inexpensive. Scaling still requires investment, but the direction points toward seaweed-derived biopolymers as functional materials in environmental remediation, not just food and nutraceuticals.