what exactly are fluorophores?
What is fluorescence, we can say that it is the ability of molecules to re-emit absorbed light at a different wavelength (that is, the ability to glow). Atoms, molecules and molecular complexes capable of fluorescing are called fluorophores, or fluorochromes. Sometimes fluorochromes are called all types of fluorescent molecules, and fluorophores are only the fluorescent components (groupings) of a large molecule. However, we will continue to use the term "fluorophore" for all types of fluorescent substances.
In research practice, a fluorescent component that is covalently attached to a macromolecule is commonly called a fluorescent label, and a free fluorophore is called a probe. Fluorophores used in microscopy are traditionally called fluorescent dyes. Finally, the fluorophores used in biological research, some authors began to call biosensors.