Time-resolved fluorescence-decay measurement and analysis on single cells by flow cytometry

Area of Science:

• Biophysics
• Analytical Chemistry
• Cell Biology

Background:

• Fluorescence spectroscopy is crucial for analyzing cellular and particle properties.
• Existing methods may lack the speed for high-throughput analysis or the precision for detailed decay measurements.
• Time-domain fluorescence-lifetime spectroscopy (TD-FLS) provides detailed decay information but can be slow.

Purpose of the Study:

• To develop a novel method for measuring and analyzing fluorescence decays of individual cells and particles in flow.
• To integrate the speed of flow cytometry with the analytical power of TD-FLS.
• To enable adaptable measurements for a wide range of fluorescence lifetimes.

Main Methods:

• A continuous wave (cw) laser is utilized for excitation.
• An electro-optic modulator is employed to pulse modulate the laser.
• The system combines flow cytometry instrumentation with TD-FLS principles.
• Excitation pulse characteristics and repetition rates are adjustable.

Main Results:

• The described method successfully measures fluorescence decays from individual cells and particles in a flow stream.
• The system's design allows for flexibility in accommodating various fluorescence lifetimes.
• The integration of flow cytometry ensures rapid sample processing.

Conclusions:

• This novel approach provides a powerful tool for high-throughput analysis of fluorescence lifetimes in biological and material samples.
• The method enhances the capability to study cellular and particle dynamics through fluorescence decay analysis.
• The adjustable parameters make the system versatile for diverse research applications in life sciences and material science.