A self-assembled fluorescent organic nanoprobe and its application for detection of sulfite in food samples and living system
Sulfur dioxide (SO2) is a widely distributed air pollutant, and human exposure and inhalation of SO2 is easily transformed into sulfite thus to induce respiratory responses and diseases. Hence, to develop a rapid, sensitive and selective method for detection of sulfites is of great importance. Herein, we designed and synthesized a novel tetraphenyl imidazole compound TIBM with characters of aggregation-induced emission enhancement (AIEE). Compound TIBM can self-assemble into well-organized nanoparticles. First demonstrated, it was an excellent probe for detection of sulfite with high selectivity and sensitivity. The nanoprobe presents great performance in the detection of sulfite with ultrafast detection time (15 s) and the ultralow detection limit (7.4 nM), which is superior to most of the reported probes. Moreover, the nanoprobe was successfully used to detect sulfite in food samples with favorable measurement accuracy. We have developed paper-based devices for the point-of-care detection of sulfite with naked eyes. Furthermore, due to the highly water solubility, cell membrane permeability and well biocompatibility the nanoproboe was further applied to detect sulfite in living system. This study may offer some helpful insights for designing other AIE-based fluorescent nanosensor for various analytes.