Fluorogenic Linkage Integration for Nonfluorescent Transformations (FLINT)

Area of Science:

• Chemical Kinetics
• Single-Molecule Imaging
• Catalysis

Background:

• Single-molecule optical imaging typically requires fluorogenic reactions.
• Nonfluorogenic reactions are challenging to study at the single-molecule level.
• Existing methods limit the scope of observable catalytic processes.

Purpose of the Study:

• To develop a novel imaging method for nonfluorogenic reactions at the single-molecule level.
• To overcome the limitations of fluorogenic probes in single-molecule catalysis studies.
• To enable high-resolution kinetic analysis of previously unobservable reactions.

Main Methods:

• Developed the Fluorogenic Linkage Integration for Nonfluorescent Transformation (FLINT) approach.
• Utilized a cascading reaction: nonfluorogenic glucose oxidation coupled with fluorogenic Amplex Red to resorufin transformation.
• Employed single-molecule turnover time analysis, cyclic voltammetry, and fluorescence spectroscopy.

Main Results:

• Successfully monitored single-turnover events and extracted kinetic parameters for nonfluorogenic glucose oxidation.
• Demonstrated FLINT's ability to distinguish reaction kinetics of coupled steps.
• Validated FLINT by comparing catalytic performances of gold nanoparticles, gold nanorods, and coronazymes.
• Evaluated chiral selectivity of d- and l-glucose on coronazymes.

Conclusions:

• FLINT is a powerful technique for single-molecule imaging of nonfluorogenic reactions.
• The approach provides high spatiotemporal resolution for kinetic analysis.
• FLINT has potential applications in studying enantioselective reactions and advancing catalysis research.