Fluorophores

Fluorophores are fluorescent chemical compounds that after exposure to light, re-emit light of a longer wavelength. This can be detected as fluorescence (Figure 1). The difference between the emission and the excitation wavelength is also called Stokes shift.

Graph representing relative intensity on the y-axis and wavelength in nanometers on the x-axis. A peak representing excitation is present at 450 nanometers. A second smaller peak at 550 nanometers represents fluorescence emission. The emission and excitation wavelength difference is represented as a double-edge arrow labeled Stokes Shift.

Figure 1: Absorption and emission spectra of a fluorophore