Direct detection of molecular intermediates from first-passage times

Area of Science:

• Physical Chemistry
• Biophysics
• Soft Matter Physics

Background:

• Energy landscapes govern natural phenomena, but their direct measurement is challenging in complex systems.
• Understanding intermediate states is crucial for elucidating molecular processes.

Purpose of the Study:

• To develop a quantitative method for investigating energy landscapes in diverse experimental systems.
• To demonstrate how first-passage time distributions reveal details about intermediate states.

Main Methods:

• Quantitative analysis of first-passage time distributions.
• Studying colloidal dynamics in confinement.
• Analyzing transport through biological pores.
• Investigating DNA hairpin folding kinetics.

Main Results:

• A short-time, power-law regime in first-passage time distributions directly correlates with the number of intermediate states.
• This finding holds true across systems with varying scales and interactions.
• The method provides insights into energy landscape details.

Conclusions:

• First-passage time distribution analysis offers a powerful tool for understanding complex molecular mechanisms.
• The number of intermediate states can be quantitatively determined.
• This method is applicable to a wide range of physical and biological processes.