Modulation of a fluorescence switch based on a photochromic diarylethene and a rhodamine B dye

A new fluorescence switch based on a photochromic diarylethene and a rhodamine B dye was designed and constructed successfully. With carefully selected components, the absorption band of the ring-closed photochromic diarylethene well overlapped with the emission band of the rhodamine B. The fluorescence emission intensity of rhodamine B is easily modulated with the photoisomerization of diarylethene by controlling the exposure time both in solution and in a solid medium. The photoswitchable system displayed high fluorescence quenching efficiency (>90%) and remarkable fatigue resistance in both solution and a solid medium. In a poly(methyl methacrylate) film, it can be repeated at least 20 cycles without observable change in emission intensity. A 99% fluorescence quenching efficiency can be achieved with an effective fluorescence change from bright wine red to the dark grey.

Graphical AbstractA new fluorescence switch based on a photochromic diarylethene and a rhodamine B dye was designed and constructed successfully. Its fluorescence changes could be easily modulated by the photoisomerization of diarylethene with high fluorescence quenching efficiency and remarkable fatigue resistance both in solution and in a solid medium.Figure optionsDownload as PowerPoint slideHighlights
► A new fluorescence switch based on a photochromic diarylethene and a rhodamine B dye was constructed.
► Its fluorescence changes could be easily modulated.
► It exhibits high fluorescence quenching efficiency and remarkable fatigue resistance both in solution and in a solid medium.