Application of fluorescence lifetime imaging (FLIM) to measure intracellular environments in a single cell

Fluorescence lifetime imaging (FLIM) has now been used in many bioscience fields, which comes from the quantification of fluorescence lifetime. The procedure for obtaining lifetime images is very similar to that used in fluorescence microscopy. However, obtaining reliable lifetime images requires an understanding of the theory of fluorescence lifetime, principle of FLIM systems, and evaluation procedure of intracellular environments. In this chapter, the materials, methods, and notes on FLIM measurements have been described, in conjunction with a brief explanation of the background of FLIM.