Photoactivatable fluorophores for durable labelling of individual cells.

We have designed and developed non-fluorescent, cell-permeable photoactivatable fluorophores, photoactivatable SPiDERs (paSPiDERs), which exhibit fluorescence activation upon light irradiation, accompanied by the generation of a quinone methide intermediate that binds covalently to intracellular proteins. The fluorescence signal is durable for 24 hours, resistant to fixation and compatible with immunostaining, and selective cell labeling can be achieved at single-cell resolution.

Silicon Rhodamine-Based Near-Infrared Fluorescent Probe for γ-Glutamyltransferase.

We designed and synthesized an activatable near-infrared (NIR) fluorescent probe for γ-glutamyltransferase, based on an asymmetric silicon rhodamine scaffold with an optimized equilibrium of intramolecular spirocyclization. The synthesized probe exhibits dramatic NIR fluorescence activation and, in combination with previously reported probes, enables discrimination of tumors with different enzymatic profiles.