Enzyme-Instructed CBT-Cys-like Click Cyclization Reactions for Bioimaging

Area of Science:

• Chemical Biology
• Bioimaging
• Organic Chemistry

Background:

• Click reactions offer high efficiency and mild conditions for bioimaging applications.
• The 2-cyanobenzothiazole (CBT)-cysteine (Cys) click reaction, inspired by firefly bioluminescence, provides rapid kinetics and excellent biocompatibility.
• Significant advancements have been made in developing enzyme-instructed CBT-Cys-based bioimaging probes over the past decade.

Purpose of the Study:

• To review the concept, mechanism, and development of the CBT-Cys click reaction and its derivatives.
• To provide a comprehensive overview of enzyme-instructed CBT-Cys-like click reaction-based probes for various bioimaging modalities.
• To discuss future challenges and opportunities in this field.

Main Methods:

• Review of existing literature on CBT-Cys click reactions and their applications in bioimaging.
• Elucidation of the reaction mechanism.
• Analysis of probe development for fluorescence, photoacoustic, magnetic resonance, and positron emission tomography imaging.

Main Results:

• The CBT-Cys click reaction and its derivatives (CHQ-Cys, PMN-Cys) demonstrate high efficiency and biocompatibility.
• Enzyme-instructed probes based on these reactions significantly enhance imaging signal and contrast.
• Applications span multiple bioimaging techniques, including fluorescence, photoacoustic, MRI, and PET.

Conclusions:

• Enzyme-instructed CBT-Cys-like click reactions are powerful tools for developing advanced bioimaging probes.
• These probes offer improved sensitivity and contrast across various imaging modalities.
• The field holds promise for future innovations in molecular imaging and diagnostics.