Thiazolyl substituted NBD as fluorescent probe for the detection of homocysteine and cysteine

Biothiols, such as glutathione (GSH), homocysteine (Hcy) and cysteine (Cys), are important biomarkers and closely related to many diseases as well as play crucial roles in many physiological processes. Thus, the detection of biothiols is highly important for early diagnosis of diseases and evaluation of disease progression. Herein, this study developed a novel fluorescent probe candidate for recognition of these biomarkers that is highly important for early diagnosis of diseases and evaluation of disease progression. The new thiazolyl substituted NBD as fluorescent probe with high selectivity and sensitivity for Hcy/Cys on account of nucleophilic substitution and Smiles rearrangement reaction. To the best of our knowledge, the thiazole-thioether has never been investigated to construct fluorescent probes. Furthermore, the probe is low toxic and has been successfully applied to detect intracellular Hcy/Cys by cell fluorescence imaging in living cells.