RuBiGABA-2: A hydrophilic caged GABA with long wavelength sensitivity

Abstract

We have devised a new caged GABA based on ruthenium bipyridyl coordination chemistry. This phototrigger delivers GABA upon irradiation with wavelengths up to 532 nm undergoing heterolytic photocleavage, in a clean and very fast (a few nanoseconds) photoreaction. With an absorptivity coefficient εMAX = 5300 M-1 cm-1 at 447 nm and a quantum efficiency φ ∼ 0.09, RuBiGABA-2 is among the most active caged-GABAs, especially at long wavelengths. This highly hydrophilic caged GABA can be synthesized in a simple one-pot reaction. The synthesis, chemical characterization and photochemical properties are presented. Finally, the usefulness of this caged compound is demonstrated by photodelivering free GABA on leech motoneurons. © 2013 The Royal Society of Chemistry and Owner Societies.