Fluorescent sensor based on CsPbBr3/HMnO2 NSs nanocomposites for the detection of ascorbic acid

Ascorbic acid (AA), a crucial antioxidant, is integral to various physiological processes in the human body and is extensively utilized as an additive in the food industry due to its potent antioxidant capabilities. Accurate and sensitive detection of AA is therefore vital for both biomedical research and food safety. Nanomaterials, with their unique physicochemical properties, have become prominent in sensing applications. Among these, perovskite quantum dots (QDs) stand out as promising fluorescent sensors due to their high quantum yield, tunable optical properties, and broad application potential. However, the limited water solubility and stability of perovskite QDs in aqueous environments have been a significant challenge. To address these issues, we have developed an innovative fluorescent sensor that integrates water-stable perovskite QDs (CsPbBr 3 QDs) with hollow mesoporous manganese dioxide nanospheres (HMnO 2 NSs). This novel sensor capitalizes on the unique hollow structure and superior redox properties of HMnO 2 NSs. The sensing mechanism is based on the reduction of HMnO 2 NSs to Mn 2+ by AA, which then triggers the fluorescence recovery of the CsPbBr 3 QDs/HMnO 2 NSs system. This mechanism enables efficient and selective detection of AA. The proposed sensor exhibits exceptional sensitivity, and demonstrates excellent selectivity against potential interfering substances. This work presents a more efficient and straightforward method for detecting AA in complex biological and food samples, highlighting its promising potential in the fields of biomedical research and food safety.