Fluorescence analysis has become a powerful tool in Biology and Medicine. Fluorescence microscopy and image technology are now widely used in many research fields. In this Chapter, most important issues are the description of cell and tissue structures as model systems, reactivity of biological substrates, binding modes of fluorochromes, fluorescence parameters, counterstaining, emission color, fading, autofluorescence, photo-enhancement, evaluation of fluorescent images, fluorescence of classical stains, etc. Some of these issues are also referred in other Chapters. In the case of reporting experimental observations and when otherwise is not stated, dyes and fluorochromes are applied simply dissolved in distilled water. Generally excitation and/or emission values are indicated directly on the figures.
Keywords: Antifading agents, Autofluorescence, Binding mechanisms, Chromogenic reaction, Competing agents, Counterstaining, Fading, Fluorogenic reactions, H bonding, Hydrophobic forces, Image processing and analysis, Lipofuscin granules, Mounting, Quenching, Reactive oxygen species.