Abstract: In this study, a novel organic-inorganic hybrid fluorescent sensor was designed and synthesized using salicylaldehyde and polyhedral oligomeric silsesquioxane (POSS) as raw materials. Through the reaction of salicylaldehyde with POSS-NH2, POSS-Sa with a salicylaldehyde-Schiff base structure was obtained, and its structure was characterized by FT-IR, UV-Vis, and NMR spectroscopy. The results revealed that the fluorescence efficiency of POSS-Sa significantly increased in the presence of zinc ions (Zn2+). As the concentration of ZnZn2+ increased, the fluorescence intensity of POSS-Sa gradually enhanced. Within a certain concentration range, the fluorescence intensity exhibited a linear relationship with Zn2＋concentration, following the calibration curve y = 10.31x +455.38（R2 = 0.997）The linear detection range was 0.5–50 × 10-7 mol·L-1, with a detection limit of 1 × 10-8 mol·L-1.This sensor demonstrated high selectivity and sensitivity toward Zn2＋and was successfully applied to the detection of Zn2+in food samples, showing high recovery rates. Additionally, due to its good biocompatibility, the sensor holds potential for Zn2+detection in food samples and in vitro cellular environments.

Key words: Polyhedral oligomeric silsesquioxane (POSS), Zn²⁺, Fluorescent probe; Salicylaldehyde Schiff