Smart sensing property of Eu3+-induced polyelectrolyte nanoaggregates on nitrofuran antibiotics in aqueous environments

Pollution of water with antibiotics is a very serious global issue. So, simple, fast, and ecofriendly detection of such pollutants in aqueous environments has aroused great attention. Several intriguing properties such as narrow emission band, large stokes shift, long luminesce decay time and resistance to photobleaching distinguishes europium-based materials from commonly used fluorophores in biology as a superior optical smart material for applications in diverse fields. Herein, strongly luminescent Eu³⁺-induced polyelectrolyte nanoaggregates (EINAP) were synthesized and successfully characterized. The biocompatible polysaccharides hyaluronic acid and chitosan are used to disperse organic europium complexes resulting in formation of hybrid nanoaggregates. As synthesized EINAP demonstrated excellent quantum yield (89.29 %) and luminescence lifetime (656 µs). The EINAP also have high sensitivity and low limit of detection with good analytical precision for nitrofuran antibiotics in aqueous environments. The luminescent nano sensor developed in this work could be a novel tool for assessment of antibiotic pollution in the environment. The overall sensing mechanisms for detection of nitrofurans in aqueous environments were found to be the combination of inner filter effect and photoinduced electron transfer respectively.