A selective colorimetric and ratiometric fluorescent chemosensor for detection of Al3+ ion

A simple Schiff-base fluorescent receptor 1 was synthesized in an one step procedure. Receptor 1 displayed a selective colorimetric change (from light yellow to light green) and high ratiometric signals upon binding to Al3+ in EtOH solution. The association constant for 1-Al3+ in EtOH was determined as 2.08×106 M−2 and the detection limit for Al3+ was determined as 5.21×10−7 M. The detection limit was sufficiently low to detect submicromolar concentration of the Al3+.