Ag2O-decorated poly(lanthanide–β-cyclodextrin) based on a silica microsphere with reversible photo-regeneration: Highly sensitive and broad-spectrum fluorescent sensing of tetracycline antibiotics

The persistent misuse of tetracycline antibiotics (TCs) has incurred severe threat to human health since it led to immune dysregulation and the emergence of drug-resistant bacteria. Thus, broad-specific and highly sensitive probe with low-price are required significantly for multiple TCs detection in practical agricultural product applications. Herein, a new coronavirus-like SiO 2 -based polylanthanide-organic fluorescence probe (SiO 2 @Eu-β-CD@Ag 2 O) was synthesized for TCs detection. Upon probing, color response was observed for TCs (pink), quinolones (cyan), and no color response to chloramphenicol or metronidazole. Moreover, a noticeable ratiometric fluorescence response at F 617 /F 592 in an “off-on” mode was observed for target tetracyclines (TC, TCH, OTC, and CTCH), with LODs ranging from 6 to 45 ng mL −1 over a wide concentration range (10–10 4 µg L −1 ). Additionally, good linear regressions and stable sensing capabilities have been observed over five recycles under nano-Ag 2 O-driven visible-light regeneration. The TC molecules within β-CD cavities through host-guest interaction can couple with Eu 3+ ions at the surface of SiO 2 , resulting in fluorescence enhancement via an “antenna effect”. Various characterizations confirm that Eu 3+ ions and nano-Ag 2 O play a crucial role in target recognition, response, and reversible regeneration of the probe. Based on the SiO 2 @Eu-β-CD@Ag 2 O probe, a smartphone-assisted paper-based sensor enables the visual and on-site detection of TCs without additional expensive instruments. A series of spiking samples, Hirudinea, Pheretima aspergillum and milk, were detected upon the probe, with recoveries from 83.9 % to 109.4 % and RSD below 4.7 %. The work offers a new strategy for antibiotics in-situ screening and sustainable monitoring adopting the novel photo-regenerated probe. • A new coronavirus-like SiO 2 -based polylanthanide-organic fluorescence probe was synthesized. • The SiO 2 @Eu-β-CD@Ag 2 O showed a typical “off–on” fluorescence response to TCs. • A ratiometric luminescent sensing platform for TCs detection was developed. • Selective recognition of TCs could be effortlessly achieved by the naked eye alone. • Nano-Ag 2 O drove reversible regeneration of the fluorescence probe under visible light.