Sense and Shoot: Multifunctional CaO2-loaded Cu-MOF nanosheets for integrated fluorescence detection and fenton-like degradation of tetracycline

Simultaneous accomplishment of sensitive detection and efficient degradation of antibiotics residues exposed in the aqueous environments has proved to be a difficult endeavor. Here, multifunctional composite CaO2-loaded Cu-MOF nanosheets (CaO2@Cu-MOF NSs) was elaborately designed and synthesized. Triggered by H+, the composite is not only capable of producing Ca2+ as the signal factor for tetracycline (TC) detection by activating the fluorescence emission of calcein, but also capable of self-supplying H2O2 and Cu2+ to construct a novel Fenton-like oxidation and O2 activation system for TC degradation based on Cu2+/Cu+ cycle. Under the synergy of target cycling and nano-enhancement, the sensing system exhibited great TC detection performance with a linear range of 0.001 to 100 ng mL-1 and detection limit of 11.8 fg mL-1. At the same time, the degradation system exhibited favorable degradation performance under the systematic action of Fenton-like and O2-activated oxidation. Nearly 80 % of the TC residues could be degraded within 10 min, and more than 95 % within 60 min. The constructed system was successfully applied to detect and degrade exposed TC in actual water samples in an integrated manner, demonstrating great promise for practical applications.