Carbazole incorporated ratiometric chemosensor for Zn2

Abstract An electron donating carbazole incorporated thiazole ( 3 ) based Zn 2+ selective intrinsic chemosensor has been synthesized and investigated. It was found that electron donating substituents such as methyl and carbazole on chemosensor ( 1 ) produce remarkable red shift in emission upon complexation with Zn 2+ . The sensor shows a selective fluorescence response with Zn 2+ over biologically relevant cations (Ca 2+ , Mg 2+ , Na + , and K + ) and biologically non-relevant cations (Cd 2+ , In 3+ and Ga 3+ ) in an aqueous ethanol system. It also produce an enhancement in the quantum yield and a longer emission wavelength shift on Zn 2+ binding with the potential of a ratiometric assay.