"Click" disaggregation-induced emission of a fluorescent dye.

Area of Science:

• Biochemistry
• Chemical Biology
• Molecular Imaging

Background:

• Fluorogenic probes are essential tools in biological research for sensitive detection.
• Many probes suffer from self-quenching at higher concentrations, limiting their utility.
• The development of probes with enhanced emission upon target binding is highly desirable.

Purpose of the Study:

• To develop a novel fluorogenic probe utilizing disaggregation-induced emission (DIE).
• To enable sensitive detection of azide-modified biomolecules through click chemistry.
• To overcome the limitations of self-quenching in traditional fluorescent probes.

Main Methods:

• Synthesis and characterization of a cationic hemicyanine (CHyC) dye.
• Investigation of CHyC's photophysical properties in aqueous buffer.
• Demonstration of fluorescence enhancement upon copper-catalyzed azide-alkyne cycloaddition (CuAAC) with azido nucleosides and DNA.

Main Results:

• The CHyC probe exhibits self-quenching in aqueous solution due to aggregation.
• Upon reaction with azide-containing molecules via click chemistry, CHyC undergoes disaggregation.
• This disaggregation leads to a significant increase in fluorescence intensity, enabling sensitive detection.
• The probe successfully labels azide-modified cellular DNA.

Conclusions:

• A new class of fluorogenic probes based on DIE has been developed.
• The CHyC probe offers a sensitive and specific method for labeling azide-modified biomolecules.
• This approach provides a valuable tool for molecular imaging and biological assays.