Rate-Engineered Plasmon-Enhanced Fluorescence for Real-Time Microsecond Dynamics of Single Biomolecules

Area of Science:

• Biophysics
• Chemical Physics
• Molecular Biology

Background:

• Single-molecule fluorescence is crucial for studying biochemical processes.
• Current methods lack the temporal resolution to observe submillisecond dynamics of transient interactions.

Purpose of the Study:

• To overcome the temporal resolution limitations of single-molecule fluorescence.
• To enable the study of molecular dynamics at microsecond timescales.

Main Methods:

• Achieved record photon count rates (>10^7 photons/s) from single plasmon-enhanced fluorophores.
• Optimized excitation and decay rates using antenna volume for maximum fluorescence intensity.
• Minimized microsecond blinking via multicomponent surface chemistry to enhance triplet decay rate.

Main Results:

• Demonstrated microsecond temporal resolution for observing DNA hybridization and transient encounters.
• Utilized nanoparticle field gradients as a molecular ruler to study intramolecular dynamics of multivalent complexes.
• Achieved unprecedented photon count rates for single-molecule studies.

Conclusions:

• The developed method provides microsecond temporal resolution for single-molecule fluorescence studies.
• This technique is compatible with existing single-molecule fluorescence setups.
• Enables real-time investigation of fast biochemical processes and molecular dynamics.