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Updated: Aug 9, 2026
09:45
Fluorescence Lifetime Imaging of Molecular Rotors in Living Cells
Published on: February 9, 2012
Fluorescence lifetime measurements in a flow cytometer by amplitude demodulation using digital data acquisition
C Deka1, L A Sklar, J A Steinkamp
1Los Alamos National Laboratory, NM 87545.
Cytometry
|September 1, 1994
Summary
We developed a digital method for fluorescence lifetime measurements in flow cytometry using amplitude demodulation. This technique complements phase-shift measurements, enhancing analytical capabilities for biological samples.
Area of Science:
- Biophysics
- Analytical Chemistry
- Optical Instrumentation
Background:
- Frequency-domain fluorescence lifetime measurements are crucial for analyzing molecular dynamics.
- Amplitude demodulation and phase-shift are complementary techniques in frequency-domain analysis.
- Existing methods face challenges in flow cytometry due to signal time-dependence.
Purpose of the Study:
- To develop a digital method for amplitude demodulation fluorescence lifetime measurements in flow cytometry.
- To address the complexities of time-dependent signals in flow-based measurements.
- To provide complementary data to phase-shift measurements for enhanced analysis.
Main Methods:
- Theoretical modeling of amplitude demodulation in flow cytometry.
- Development of a digital data acquisition technique for amplitude demodulation.
- Experimental verification using fluorescent microspheres in a flow cytometer.
Main Results:
- A practical method for amplitude demodulation lifetime measurements in flow was developed.
- Experimental results using fluorescent microspheres showed good agreement with static measurements.
- The digital method successfully addressed challenges of time-dependent signals.
Conclusions:
- The developed method enables amplitude demodulation fluorescence lifetime measurements in flow cytometry.
- This technique enhances analytical capabilities by complementing phase-shift data.
- The findings support the integration of amplitude demodulation into advanced flow cytometry systems.
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