Time-resolved ratio method for multicomponent fluorescence pattern analysis using a fluorescence lifetime imaging system

Time-resolved ratio method is described for multicomponent pattern analysis by using a fluorescence lifetime imaging system and a ratio method calculation. Nanosecond-level time- resolved fluorescence images of a sample under a pulsed light excitation were detected directly by using a gated microchannel plate (MCP) image intensifier coupled to a CCD camera. Differences in fluorescence lifetimes of components in which each component has similar fluorescence wavelength characteristics were positively utilized to estimate every component spatial distribution. Spatial deconvolution of multicomponent fluorescence data was rapidly carried out from a set of time-resolved, two-dimensional fluorescence data. An application of a multigate time-resolved ratio method for fluorescence pattern analysis was provided. From the results, it is shown that the new method can be successfully used for multicomponent fluorescence pattern analysis at a reasonable signal-to-noise ratio.