The preparation of a chitosan-based novel fluorescent macromolecular probe and its application in the detection of hypochlorite

In this paper, a novel fluorescent probe with high sensitivity and selectivity to hypochlorite (ClO−) was prepared by an acylation reaction and Suzuki coupling reaction. The probe takes chitosan and 4-bromo-1, 8-naphthalene as raw materials and, a fluorescent test paper for ClO− detection in water was prepared using this new probe. The structure of this new fluorescent chitosan was analyzed by Fourier Transform infrared spectroscopy, nuclear magnetic resonance, an energy dispersive X-ray spectrometer, a scanning electron microscope, and an X-ray diffractometer. The properties of this probe were characterized by a thermogravimetric analyzer, ultraviolet–vis spectrophotometer, and fluorescence spectrophotometer. The results show that the expected probe is successfully synthesized and the probe has good thermal stability. Furthermore, the fluorescence probe can detect ClO− quickly and has a good selectivity and anti-interference. When ClO− was added within 8 min, the test paper showed a noticeable change from yellow to blue.