NIR‐II Fluorescent Probe for Detecting Trimethylamine Based on Intermolecular Charge Transfer

Abstract A new kind of small organic NIR‐II fluorophore molecule (ZS‐1010) based on intermolecular charge transfer was developed as a NIR‐II fluorescent probe for trimethylamine (TMA) detection, which is important for the diagnosis of cardiovascular disease, chronic kidney disease and diabetes. ZS‐1010 has a strong push–pull electron system composed of electron donor unit and electron acceptor unit, exhibiting strong absorption and emission in the NIR‐II region. When mixed with TMA which possesses strong electron‐donating characteristics, the push–pull system of ZS‐1010 will be affected along with the dipole moment change, leading to the quenching of fluorescence. This is the first example of TMA fluorescent probe in the NIR‐II window showing deep penetration, fast response speed, high selectivity and pH stability.