Ultrabright orange-emitting AIE nanodots-based lateral flow assay for rapid and sensitive detection of Pseudomonas aeruginosa in drinking water

Pseudomonas aeruginosa , a hazardous pathogen, poses a significant public health risk through its potential contamination of drinking water. Current culture-based detection methods remain limited by their prolonged duration and operational complexity. In this study, ultrabright orange-emitting aggregation-induced emission nanodots (AIENDs) were successfully prepared through a self-assembly approach constructing a metal-polyphenol network formed by coordination between tannic acid and Zr 4+ . The synthesized ultrabright orange-emitting AIENDs demonstrated excellent biocompatibility and enabled direct conjugation with anti- P. aeruginosa monoclonal antibodies (mAbs) without the need for coupling reagents, enabling rapid antibody immobilization with a coupling efficiency exceeding 94 %. The resulting fluorescent probe (AIEND@mAbs) was employed as an amplified signal reporter in a lateral flow immunoassay (LFIA), establishing a sensitive and rapid quantitative detection platform for P. aeruginosa . This AIENDs-LFIA achieved a linear detection range of 1.0 × 10 3 to 5.0 × 10 4  CFU/mL, with a detection limit of 9.74× 10 2  CFU/mL within 15 min. Comparative analysis revealed that the AIENDs-LFIA exhibits 2.2- to 5.7-fold higher sensitivity than conventional LFIAs that use fluorescent microspheres or gold nanoparticles. Furthermore, spiked-recovery experiments in tap water, mineral water, and purified water yielded acceptable recoveries and satisfactory precision. These results demonstrate the AIENDs-LFIA as a promising, efficient, and practical tool for monitoring pathogenic bacteria in drinking water.