Scanning fluorescence correlation spectroscopy (SFCS) with a scan path perpendicular to the membrane plane

Area of Science:

• Biophysics
• Membrane Biophysics
• Spectroscopy

Background:

• Scanning fluorescence correlation spectroscopy (SFCS) enables diffusion and interaction studies in biomembranes.
• Conventional confocal laser scanning microscopy (CLSM) requires specialized data evaluation for SFCS.

Purpose of the Study:

• To introduce a method for measuring diffusion and interactions of fluorescent components in free-standing biomembranes using SFCS.
• To develop user-friendly software for SFCS data analysis.

Main Methods:

• Utilized a confocal laser scanning microscope (CLSM) to scan a detection volume through the membrane plane at kHz frequencies.
• Developed two open-source software tools, PyScanFCS and PyCorrFit, for data processing and analysis.
• Applied SFCS in one- or two-focus and single- or dual-color modalities.

Main Results:

• Successfully implemented SFCS for biomembrane analysis.
• Provided efficient data evaluation pipelines for SFCS measurements.
• Enabled detailed investigation of fluorescent component dynamics within membranes.

Conclusions:

• PyScanFCS and PyCorrFit significantly streamline SFCS data analysis.
• The developed software facilitates the establishment of perpendicular SFCS for biomembrane research.
• This approach offers a powerful tool for understanding molecular behavior in membranes.