Visual Detection of Methylglyoxal in Multiple Scenarios via NIR-Excitable Reversible Ratiometric Fluorescent Hydrogel Sensor

Methylglyoxal is considered a key indicator in evaluating wine flavor and quality, as well as an important marker for diabetic pathological syndromes. Rapid and accurate quantitative detection of methylglyoxal is essential in scenarios of wine production standards and human health monitoring. Herein, we report a visual method for detecting methylglyoxal via an NIR-excitable reversible ratiometric fluorescent hydrogel sensor, where NIR-excited upconversion nanoparticles serve as energy donors and eosin B acts as the energy acceptor, together forming an integrated ratiometric nanophotonic probe that ensures the accuracy of detection without being affected by various background fluorescence interference in different scenarios. The integrated optical probe is combined with a 3D network hydrogel to design a sensing patch that can be easily regenerated through simple treatment, exhibiting a distinct optical color response. Upon the addition of methylglyoxal, the G/R value of the sensing patch changes, enabling the real-time quantitative detection of methylglyoxal. Additionally, we combined the hydrogel sensing patch with a smartphone to create a portable sensing platform for the convenient visual detection of methylglyoxal. The probe and hydrogel sensing patch have detection limits for methylglyoxal as low as 59 and 75.4 nM, respectively. The portable sensing patch designed here provides an effective strategy for standardizing the wine production process and monitoring patient health.