Basic Introduction to Fluorescence Microscopy

Basic Introduction to Fluorescence Microscopy

Fluorescence is a part of the luminescence family. Luminescence is a process by which molecules emit light from either absorbing light, from mechanical friction or by a chemical mechanism. The generation of luminescence through the excitation of a molecule using ultraviolet or visible light photons is called  photoluminescence, which is divided into two categories, fluorescence andphosphorescence. Fluorescence is the property of molecules to absorb light at a particular wavelength and to then emit light of a longer wavelength after a brief interval called the fluorescence lifetime. Phosphorescence occurs in the same way as fluorescence, but with a much longer "excited" state lifetime. When fluorescence is coupled with an optical microscope, it can help microscopists study a wide variety of phenomena in biology. Primary biological uses for fluorescence include the analysis of intracellular distribution in sub-cellular assemblies such as nuclei,membranes, cytoskeletal filaments, mitochondria and others. In addition to observations of cellular anatomy, fluorescence is also useful in "time-resolved measurements" like intracellular dynamics and the interactions between various molecules including diffusion, binding constants, enzymatic reaction rates and other reaction mechanisms. Other cellular functions important processes are also targets for fluorescence investigation such as endocytosis, exocytosis, signal transduction and transmembrane potential generation. Fluorescence microscopy can be an invaluable tool for investigation. The use of fluorochromes has made it possible to identify cells and sub-microscopic cellular components and other entities with a high degree of specificity when used amidst non-fluorescing materials. As few as 50 molecules per cubic micrometer can be detected with fluorescence. Although a fluorescence microscope cannot provide spatial resolution below the diffraction limit of the specimen, the presence of fluorescing molecules below such limits can still be observed. The field of fluorescence microscopy is currently experiencing a renaissance with the introduction of new fluorochromes and techniques such as confocal, multiphoton, deconvolution, and total internal reflection. Green Fluorescence Protein is a fluorochrome that is rapidly becoming a labeling method of choice for molecular and cellular biologists who can explore biochemical events in living cells with natural fluorophores. Meiji Techno's entrance into this exciting field was realized with the release of the TC Series of  Inverted Biological Microscopes and then later with the upright MT6000 Series. Meiji equips their fluorescence models with filters that can be used with EGFP and GFP fluorochromes. For customers wanting to use the other of the hundreds of fluorochrome probes available to biologists, Meiji has partnered with Chroma Technology. Chroma can help your end user select the filters they need to work with their chosen technique and fluorochrome. read more here