Sensing Mechanism of Cysteine Specific Fluorescence Probes and Their Application of Cysteine Recognition

Due to the biological importance of cysteine (Cys), the development of organic fluorescence probes for Cys has been a wide, potent, and outstanding research field in most recent years. It has been used as a biomarker in treating various diseases; therefore, developing a sensing mechanism for detecting Cys is very important. In this Review, we focus on and summarize the specific results of recent exciting literature regarding the sensing mechanism of Cys-specific fluorescence probes and their applications in Cys recognition. Moreover, a design strategy of the sensing mechanism of Cys can be classified into seven reaction mechanisms, including the aromatic substitution rearrangement reaction, cyclization of aldehyde, Michael addition reaction, Se–N or S–S or bond cleavage reaction, addition cyclization of acrylate, metal complex reaction, and nucleophilic substitution reaction. In all sections, discussions have corresponded to Cys-specific sensing mechanisms, which consist of emission, color changes, and detection limits and deal with the application and recognition sites of molecules. Future directions and challenges have been proposed for the preparation of Cys-specific probes.