Zn2+-induced conformational changes in a binaphthyl-pyrene derivative monitored by using fluorescence and CD spectroscopy

We have developed a unique binaphthyl-pyrene system 1, whose dihedral angle is reversibly modulated by the addition of Zn2+. Dihedral angle changes in this system were monitored by using circular dichroism (CD) and by an observed off-on'' fluorescence enhancement in aqueous solution. Owing to these changes, the presence of biologically important Zn2+ ions in samples can be readily monitored by employing CD and fluorescence spectroscopy. Finally, the experimental observations made in this effort are supported by the results of quantum mechanical calculations.