Bioorthogonal Turn‐On Probes for Imaging Small Molecules inside Living Cells

Abstract
Glowing tags: A series of activatable (“turn‐on”) tetrazine‐conjugated fluorescent probes was developed, which react rapidly in an inverse‐electron‐demand [4+2] cycloaddition with strained dienophiles such as trans‐cyclooctene, thereby strongly increasing the fluorescence intensity (see picture). The novel turn‐on probes were applied for intracellular live‐cell imaging of a microtubuli‐binding trans‐cyclooctene modified taxol.