Theory of fluorescence correlation spectroscopy at variable observation area for two-dimensional diffusion on a...

Area of Science:

• Biophysics
• Physical Chemistry

Background:

• Two-dimensional diffusion of tagged particles, like plasmic membrane constituents, can be hindered by barriers.
• Numerical investigations suggest fluorescence correlation spectroscopy at variable observation area can detect these barriers.

Purpose of the Study:

• To present a complete theory confirming and accounting for numerical findings.
• To enable reliable, quantitative exploitation of experimental data for barrier detection.
• To extract sub-wavelength mesh size information.

Main Methods:

• Theoretical modeling of fluorescence correlation spectroscopy.
• Analysis of experimental data for quantitative exploitation.

Main Results:

• Confirmation and theoretical accounting for numerical findings on barrier detection.
• Development of a method for quantitative data exploitation.
• Extraction of sub-wavelength mesh size.

Conclusions:

• Fluorescence correlation spectroscopy at variable observation area is a viable method for detecting mesh-like barriers.
• The presented theory allows for quantitative analysis and extraction of mesh size.
• Experimental time-scales for optimal data acquisition are discussed.