A simple fluorescent probe for fast and sensitive detection of inorganic phosphate based on uranine@ZIF-8 composite

A fluorescent probe for inorganic phosphate (Pi) was rationally designed. The probe was constructed by loading uranine in zeolitic imidazolate framework-8 (ZIF-8), during which aggregation-caused quenching occurred. In the presence of Pi, uranine was released owing to the decomposition of ZIF-8, thus leading to fluorescence enhancement. The probe was facilely prepared by a one-step method at room temperature, and possessed a fast response of 3 min and a low detection limit of 0.2 μM. It was further applied to the detection of Pi in urine, and satisfactory recoveries were obtained (93.5–96.0%). This work not only develops an effective tool for Pi detection but also proposes a new strategy to design fluorescent probes for Pi.