A camphor-based fluorescent probe with high selectivity and sensitivity for formaldehyde detection in real food samples and living zebrafish

A novel and simple camphor-based fluorescent probe (CH) was synthesized for detecting formaldehyde (FA) with high specificity and efficiency. A significantly enhanced green fluorescence was clearly observed only with the addition of FA because of specific recognition site homoallylamino group of FA. After treating with FA, the homoallylamino group on probe CH was converted to aldehyde group via the 2-aza-Cope rearrangement mechanism, which was demonstrated with high-resolution mass spectrometer (HRMS) analysis and density functional theory (DFT). Moreover, the experiment results manifested that the detection of FA with probe CH can be performed in a nearly perfect aqueous solution with low detection limit, large Stokes shift and wide pH adaptation range. Meanwhile, a simple filter paper, loaded with probe CH, was available to detect gaseous FA. The probe CH was also successfully applied to the detection of FA in real food and water samples. Furthermore, the fluorescence imaging experiment verified that the probe CH can effectively monitor FA in living zebrafish.