A novel fluorescent sensor for Al 3+ based on a new diarylethene with a naphthalimide unit

Abstract

Abstract A new fluorescent sensor for Al 3+ based on a photochromic diarylethene with a naphthalimide unit has been synthesized. Its photochromic and fluorescent properties with UV/Vis light and Al 3+ /EDTA were investigated systematically in methanol. The fluorescent sensor was highly selective toward Al 3+ with obvious emission intensity change (enhanced more than 20-fold) and color change (dark to orange-yellow). The Job’s plot showed the 1:1 complex of the sensor with Al 3+ . Moreover, the complexation mechanism of the sensor with Al 3+ was confirmed by the ESI–MS and 1 H NMR titration experiment. The binding constant ( Ka ) was 2.55 × 10 5 mol −1 L and the limit of detection of the sensor for Al 3+ was calculated to be 1.75 × 10 −7 mol L −1 . In addition, the metal-responsive fluorescence behavior of the sensor was applied successfully to the construction of molecular logic circuit.