A novel ratiometric formaldehyde fluorescent probe for applications in environmental, food, and biological systems

Formaldehyde (FA) is a toxic, irritating, colorless gas molecule widely used in food preservation, construction, paint, pharmaceutical and chemical industries. However, FA may enter the air, water and soil during its release, causing ecological damage and jeopardizing human health. Therefore, it is significant to seek a simple and effective assay for detecting FA in environment, food, and biological systems. Here, we designed and synthesized a novel phenothiazine-based fluorescent probe, JD-1, which exhibits ratiometric emission responses to FA at 400 nm and 505 nm. In addition, a solid sensor prepared by loading the probe JD-1 onto filter paper successfully achieved visual detection of liquid and gaseous FA. Notably, to further investigate the application scenarios of probe JD-1 in the detection of FA, we also prepared electrostatically spun fiber membranes by mixing probe JD-1 with PVDF-HFP, which were successfully used for the selective detection of FA. And the probe JD-1 possessed excellent stability in the detection of FA in real food samples, soil, live cells and zebrafish. Thus, this probe provides an attractive assay for the detection of FA in environment food, biological systems.