Article pubs.acs.org/JACS
Calcium Uncaging with Visible Light Hitesh K. Agarwal,†,∥ Radoslav Janicek,§,∥ San-Hui Chi,‡ Joseph W. Perry,‡ Ernst Niggli,*,§ and Graham C. R. Ellis-Davies*,† †
Department of Neuroscience, Mount Sinai School of Medicine, New York, New York 10029, United States Department of Physiology, University of Bern, Bern CH 3012, Switzerland ‡ School of Chemistry and Biochemistry, Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, Georgia 30332, United States §
S Supporting Information *
ABSTRACT: We have designed a nitroaromatic photochemical protecting group that absorbs visible light in the violet-blue range. The chromophore is a dinitro derivative of bisstyrylthiophene (or BIST) that absorbs light very effectively (ε440 = 66,000 M−1 cm−1 and two-photon cross section of 350 GM at 775 nm). We developed a “caged calcium” molecule by conjugation of BIST to a Ca2+ chelator that upon laser flash photolysis rapidly releases Ca2+ in
