FLUORESCENCE ENHANCEMENT OF Al3+-SODIUM MORIN-5-SULFONATE COMPLEX BY IMIDAZOLIUM IONIC LIQUID AND ITS APPLICATION IN DETERMINATION OF Al3+ IONS IN AN AQUEOUS SOLUTION

This study describes the preparation of sodium morin-5-sulfonate (NaMSA) as a new reagent for the determination of aluminium(III) (Al3+) ions based on the formation of a ternary complex. The complex consists of Al3+, NaMSA, and 1-Butyl-3-methylimidazolium hexafluorophosphate (BMIM-PF6). It was found that this method was sensitive compared to the binary complex of Al3+ and NaMSA. The ternary complex was excited at 420 nm, and the fluorescence signal was measured at 518 nm. Maximum fluorescence signal produced at pH 5.0 (acetic acid-acetate buffer), with 0.02% v/v BMIM-PF6 and 1.0 x 10(-4) molL(-1) of NaMSA. The calibration graph in linear up to 10 mgL(-1) with the calculated detection limit of 0.017 mgL(-1). Effect of foreign ions towards the ternary complex was also studied. Finally, the method was applied in the determination of Al3+ ions in water samples, and satisfactory results were obtained.