The Chemistry of Small-Molecule Fluorogenic Probes - Progress in Molecular Biology and Translational Science - page 27

amidation of the ortho -carboxyl group to yield colorless nonfluorescent
lactams. This can be used to prepare reversible or irreversible fluorogenic
molecules.
FRET and PeT are alternative methods to modulate fluorescence inten-
sity. These strategies are especially useful for fluorophores that lack obvious
points of attachment for blocking groups, such as the BODIPY dyes and
some cyanine derivatives. In particular, sensors based on PeT have enabled
important biological experiments to visualize changes in ionic concentra-
tion. Finally, dyes that exhibit intrinsic sensitivity to the environment, such
as phenoxazines, can serve as valuable fluorogenic compounds without the
need for attachment of any moiety.
The design principles of fluorogenic molecules are well established.
Future advances in small-molecule fluorogenic compounds will depend
on improved synthetic methods to efficiently build finely tuned derivatives
for specific biological experiments. Efficient generation of libraries of dyes
will allow the discovery of additional probes with intrinsic sensitivity and
affinity for different cellular environments. Moreover, advances in the
chemistry of fluorescent probes will allow the synthesis of new hybrid struc-
tures that combine advantages of multiple dyes to create fluorogenic probes
of ever-increasing sophistication.

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