A “turn-on” fluorescent sensor for the selective detection of erythromycin in aqueous solution

The accurate and rapid detection of erythromycin (ERY) is of great significance to environmental protection and human health. Herein, a "turn-on" fluorescent sensor was developed for the quantitative detection of ERY in aqueous solution. The probe Cu-BDC-NH₂ exhibits weak blue emission due to the ligand-to-metal charge transfer (LMCT) effect. Upon the addition of ERY, the fluorescence intensity increases by 436%, whereas other similar antibiotics lead to fluorescence quenching. The sensing mechanisms were thoroughly investigated by powder X-ray diffraction, fluorescence lifetime measurements, UV-vis spectroscopy and X-ray photoelectron spectroscopy. Owing to the excellent selectivity and sensitivity, test strips based on the probe were further prepared to evaluate the practical applicability in real samples.