Frequency-Domain Fluorescence Spectroscopy

Abstract

In this chapter we described instrumentation, basic theory, and applications of first- (1-200 MHz) and second-generation (2 GHz) frequency-domain fluorometers. The frequency-domain data provide excellent resolution of time-dependent spectral parameters. It is possible to resolve closely spaced fluorescence lifetimes, even in the picosecond region, and to determine multiexponential decays of anisotropy. Correlation times as short as 10 ps have been measured. Several novel applications are described, including picosecond fluorescence of hemoglobin and enhanced resolution of anisotropy decays using combination quenching and multiwavelength global measurements and analysis, as well as unusual behavior of phase and modulation data for associated anisotropy decays