Metal–organic cages ZrT-1-NH2 for rapid and selective sensing of nitrite

Herein, a label-free, sensitive, and selective fluorescence probe for the detection of trace nitrite in water sample by metal–organic cages (ZrT-1-NH 2 ) was reported. The fluorescence emission of as-prepared ZrT-1-NH 2 was 450 nm upon the excitation of 373 nm with a quantum yield of about 8.6%, which can be quenched by the addition of nitrite. The proposed sensor owned the advantages of high sensitivity (limit of detection = 0.5 µM), quick response (100 s), and excellent selectivity in the presence of various ions. The fluorescence quenching was due to the diazotization and reduction reaction of –NH 2 with the preliminary studying. Under the optimized condition, the sensor was successfully exemplified by real water samples and comparative performance was achieved.