Translator Disclaimer
10 May 2001 Flow cytometric time-resolved measurements by frequency heterodyning of fluorescence emission signals
Author Affiliations +
Proceedings Volume 4260, Optical Diagnostics of Living Cells IV; (2001)
Event: BiOS 2001 The International Symposium on Biomedical Optics, 2001, San Jose, CA, United States
A first generation phase-sensitive flow cytometer has been developed that combines flow cytometry (FCM) and fluorescence lifetime spectroscopy measurement principles to provide unique capabilities for making time-resolved fluorescence measurements in the frequency-domain or particles/cells labeled with fluorescent probes. Cells are analyzed as they flow through a chamber and intersect a high-frequency, intensity-modulated (sine-wave) laser excitation beam. Fluorescence emission signals are currently processed by analog homodyne methods to quantify lifetimes and resolve heterogeneous fluorescence based on differences in lifetimes expressed as phase shifts, while maintaining the capability to make conventional FCM measurements. in this study we report the current status of our phase flow cytometer using homodyne signal processing, including recent applications, along with the description of a flow cytometric method for quantifying fluorescence lifetimes by frequency heterodyning techniques. Lifetimes are determined from homodyned and heterodyned (1 MHz difference frequency) signals using analog signal processing electronics. These signals are then digitized and displayed as frequency distribution histograms in real time.
© (2001) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
John A. Steinkamp and Jimmie D. Parson "Flow cytometric time-resolved measurements by frequency heterodyning of fluorescence emission signals", Proc. SPIE 4260, Optical Diagnostics of Living Cells IV, (10 May 2001);

Back to Top