Fluorochromes have unique and characteristic spectra for absorption (excitation) and emission. A single dye
is excited at a particular wavelength and emits a photon at a higher wavelength. A tandem dye consists of a
donor and acceptor fluorochrome molecule, placed in close proximity, allowing for energy transfer between
the two. The tandem dye is excited at the excitation wavelength of the donor molecule and emits a photon at
the emission wavelength of the acceptor molecule.
Fluorescence is the process of light emission by a substance (fluorochrome) that has previously absorbed electromagnetic radiation. Each fluorochrome has a unique and characteristic spectrum for absorption (excitation) and emission.
This poster includes an explanation of how fluorescent dyes work, an overview of the differences between single and tandem dyes, as well as a table of the most commonly used fluorochromes and their excitation and emission wavelengths.