TIME-RESOLVED FLUORESCENCE-DECAY MEASUREMENT AND ANALYSIS ON SINGLE CELLS BY FLOW-CYTOMETRY

A novel method is described for the measurement and analysis of fluore scence decays of individual cells and particles in flow. It combines t he rapid measurement capabilities of a flow cytometer and the robust m easurement and analysis procedures of time-domain fluorescence-lifetim e spectroscopy. For excitation we use a cw laser that is pulse modulat ed by an electro-optic modulator. The characteristics and the repetiti on rate of the excitation pulses can be easily adjusted to accommodate fluorescence decays with a wide range of lifetimes. (C) 1996 Optical Society of America