Epifluorescence microscopy is a technique which is widely used by biologists. In some cases it involves auto or primary fluorescence which occurs with some substances such as chlorophyll. More often it involves staining with a special type of histological stain called a fluorochrome which is only taken up by specific material or hybridization of fluorescently labeled complementary DNA sequences. High energy, short wavelength (eg. UV or blue) light is directed onto the preparation and lower energy, longer wavelength (eg. green or red) light is emitted.
Bacteriology, Environmentally samples in situ, Mammalian Cells, Medical