A recyclable fluorescent probe for picric acid detection in water samples based on inner filter effect

1-Aminopyrene@ZIF-8 composite was synthesized as the fluorescent probe for picric acid (PA) based on inner filter effect. The probe displayed selective response toward PA within 10s, and a linear range was obtained from 1 to 150μM with detection limit of 0.3μM, which is much lower than the permissible level of PA in drinking water reservoir (0.5mgL^-1/2.2μM) set by China's State Environmental Protection Administration (GB3838-2002). Most importantly, the probe possessed excellent recyclability and could be recycled for at least six times. It was further applied to the detection of PA in water samples, and satisfactory recoveries were obtained in the range of 96.0-104.0%.