Bidirectional rapid sensing based on rare-earth upconversion nanoparticles for the ascorbic acid and hydrogen peroxide detection

Abstract

The current detection methods for L-Ascorbic Acid (AA) and hydrogen peroxide (H₂O₂) often face limitations in sensitivity, rapidity, and practical application. Addressing these challenges, this study introduces a bidirectional rapid sensing platform based on rare-earth upconversion nanoparticles (UCNPs) for the detection of AA and H₂O₂. The developed probe, combining Tm-doped NaYF₄ UCNPs with an iron chelate (SA-Fe^III), leverages the inner filtration effect for efficient detection. By employing both fluorescence and colorimetric methods, the proposed system achieves linear detection ranges of 0–100 μM for AA and 0–71.7 μM for H₂O₂, with detection limits as low as 0.1 μM and 0.45 μM, respectively. Furthermore, a smartphone-based image analysis technique demonstrates the potential for rapid, on-site concentration measurements. This work significantly enhances the practicality of AA and H₂O₂ detection, offering a sensitive, fast, and user-friendly approach that holds promise for applications in clinical diagnostics, food safety, and agricultural stress monitoring.