LAUSR

BACKGROUND Ascorbic acid (AA) is an essential nutrient for humans, which must be obtained from vegetables, fruits and other foods. The content of AA has become an important standard to evaluate the quality and nutritional value of food. The fluorescence sensing method based on nanomaterials is a good alternative for the rapid detection of AA. In this study, we developed an inner filter effect-based fluorescent probe which hybridized the N-doped carbon dots (NCDs) with the cobalt oxyhydroxide nanoflakes (CoOOH NFs). RESULTS An optimal NCDs was successfully selected because it has a strong fluorescence at 430 nm and the most significant quenching phenomenon with CoOOH NFs due to the inner filter effect. When adding AA into the NCDs-CoOOH NFs probe solution, a specific REDOX reaction will occur between the enediol group of AA and the CoOOH NFs to interfere with the quenching ability of CoOOH NFs and recover the fluorescence of NCDs. The recovered fluorescence intensities demonstrated a linear relationship with the concentrations of AA. The assay based on NCDs-CoOOH NFs probe allows AA to be tested in a wide range of 5 - 200 μM with the detection limit of 2.31 nM. Furthermore, to evaluate its practical application, the NCDs-CoOOH NFs fluorescence probe was utilized to analyze AA in vegetable, fruit, and serum matrixes with satisfactory results. CONCLUSION An inner filter effect-based fluorescence probe for the rapid detection of AA was developed, and it has a good potential to be applied in both food and clinical testing. This article is protected by copyright. All rights reserved.