A Blue Light and Two‐Photon Activatable Rhodamine Fluorophore

Photoactivatable fluorophores (PAFs) are powerful tools for biological imaging applications because they provide spatiotemporal control of fluorescence distribution. Many of the existing PAFs can only be activated by UV irradiation. In our study, we present a blue light (1P) and NIR light (2P) activatable rhodamine fluorophore. Next to the description of the synthesis and the investigation of the photoreaction, we demonstrate the use of our PAF in the context of laser scanning microscopy. By immobilization of our PAF in a hydrogel, we were able to write and read spatially resolved illumination patterns with excellent contrast after both one-photon and two-photon excitation.