Sea pineapple-inspired multifunctional filter with ZIF-67 for simultaneous microfiber and dye removal

The widespread release of microfibers (MFs) from household laundry and the persistence of cationic dyes such as methylene blue (MB) represent critical threats to human health and aquatic ecosystems. Current commercial laundry filters and dye-removal methods remain limited by moderate capture efficiencies, clogging, and lack of simultaneous pollutant removal functions. To address these challenges. To address these challenges, a bioinspired gill-with-cilia filter (GCF) was developed by biomimicking the branchial basket and ciliated pharyngeal bars of the sea pineapple (Halocynthia roretzi) and functionalized with ZIF-67 for enhanced removal of both MFs and dyes. The GCF was fabricated as a cylindrical lattice with integrated cilia-like elements to replicate crossflow filtration, ensuring clog resistance and enhanced particle capture. Performance evaluation demonstrated a maximum MF removal efficiency of 97.03 %, surpassing commercial devices, and stable reusability with efficiencies maintained above 97 % over 10 washing cycles with minimal flow rate reduction (11.46 %). In addition, ZIF-67 functionalization endowed the GCF, enabling simultaneous removal of MB dye, with 94.1 % removal at pH 8.5, attributed to enhanced hydrogen bonding and π–π stacking interactions. Importantly, real-washing machine tests confirmed the robustness and scalability of the GCF for practical applications. This study introduces, for the first time, a multifunctional sea pineapple-inspired filtration system, bridging biological design principles and advanced materials engineering to provide an effective solution for MF and dye pollution in laundry effluents.