Time-resolved methods in biophysics. 9. Laser temperature-jump methods for investigating biomolecular dynamics

Area of Science:

• Biophysics
• Biomolecular Kinetics
• Spectroscopy

Background:

• Many critical biochemical processes occur on nanosecond to microsecond timescales, previously inaccessible to direct experimental study.
• The development of laser temperature-jump (T-jump) techniques revolutionized the study of these fast biological dynamics.

Purpose of the Study:

• To review the principles, historical development, and applications of laser T-jump methodology in biophysics.
• To provide a comprehensive overview of experimental considerations and apparatus designs for laser T-jump experiments.

Main Methods:

• Overview of T-jump relaxation kinetics and historical evolution of laser T-jump methods.
• Summary of physical principles, including Raman conversion for heating pulses.
• Discussion of experimental considerations: jump size, duration, uniformity, and mitigation of adverse effects (photo-acoustic waves, cavitation, thermal lensing).

Main Results:

• Detailed description of the laser T-jump apparatus developed at the NIH Laboratory of Chemical Physics.
• Survey of other contemporary laser T-jump designs.
• Review of diverse applications demonstrating the technique's versatility and impact.

Conclusions:

• Laser T-jump methodology is a versatile and broadly applicable technique for studying fast biomolecular kinetics.
• The technique has yielded significant new results and insights into the dynamics of biomolecular processes across various fields of biophysics.