Calibration approaches for fluorescence lifetime applications using time-domain measurements

Area of Science:

• Spectroscopy
• Biophysics
• Analytical Chemistry

Background:

• Accurate fluorescence lifetime measurements are crucial for understanding biological systems.
• Instrument response functions (IRF) and reference dye calibration are essential for reliable time-domain fluorescence lifetime data.
• Standardized protocols are needed for consistent instrument performance and data interpretation.

Purpose of the Study:

• To present detailed experimental protocols for acquiring IRF and calibrating instruments for time-domain fluorescence lifetime measurements.
• To guide researchers in sample preparation and instrument setting optimization for one- and two-photon excitation.
• To provide troubleshooting strategies for common issues encountered during instrument calibration and data acquisition.

Main Methods:

• Detailed step-by-step protocols for preparing calibration samples (scatter solutions, second harmonic generating crystals, reference dyes).
• Explanation of instrument settings for both one- and two-photon excitation modes.
• Demonstration of expected IRF curves and reference decays with experimental examples.

Main Results:

• Experimentally acquired examples of IRF curves and reference decays are presented.
• Troubleshooting guidance is provided for distorted experimental results.
• The importance of IRF and reference dye calibration for data accuracy is highlighted.

Conclusions:

• Implementing these protocols ensures accurate instrument response function acquisition and calibration.
• Proper calibration is vital for reliable time-resolved instrument parameter adjustment and data analysis.
• This work facilitates the comparison and extrapolation of fluorescence lifetime values across diverse biological systems.