Activatable NIR-II Fluorescent Nanoprobe for Rapid Detection and Imaging of Methylglyoxal Facilitated by the Local Nonpolar Microenvironment

Closely related to multiple chronic inflammation, especially type-2 diabetes (T2D), methylglyoxal (MGO) may be a potential key to visualize disease progression and treatment effects. On the other hand, lack of convenient and fast analytical methods cannot afford accurate MGO quantitative evaluation. In this work, an activatable second near-infrared region (NIR-II) fluorescent probe TDTCD was synthesized and its reaction mechanism with MGO was discussed. The desired NIR-II product preferred response solvents with small polarity. A novel activatable nanoprobe, MG-SLNP, for MGO was then constructed based on rational packaging to provide a local nonpolar microenvironment. The hydrophobic core of nanoparticles not only successfully improved the stability and water solubility but also greatly promoted the response rate while reacting with MGO. The comparison between NIR-II fluorescence and the traditional high-performance liquid chromatography method for T2D blood samples was discussed. A high-resolution viewing window, quick response, and good biocompatibility led to a satisfactory signal-to-noise ratio of MG-SLNP for real-time MGO bio-detection and imaging in vivo.