Study of the removal of microplastics in aquatic environments using Sargassum spp. from the Mexican Caribbean

Abstract This study evaluates the potential of the macroalgae Sargassum spp. as a low-cost biosorbent for the removal of polyethylene terephthalate (PET) and polymethyl methacrylate (PMMA) microplastics in aqueous solutions. To quantify removal, the microplastics were stained with methylene blue at a known concentration, such that the concentration of the dye is inversely proportional to the concentration of microplastics present in the samples. The results show that Sargassum spp. can remove up to 30% of PET particles, compared to 10% in the case of PMMA. This difference is attributed to the greater chemical affinity of PET with the functional groups present in the biomass of the algae. The Sargassum spp. samples were characterized by microscopy, corroborating the removal of microplastics. This approach offers a dual benefit, transforming a pressing environmental issue in the Caribbean into a valuable resource while contributing to the reduction of microplastic pollution. Graphical abstract