| Aluminum (Al) is a toxic metal at high levels and has been involved as a causative factor in several diseases,
therefore, its determination in different samples is very important. METHODS: In this study a method based on cloud point
extraction (CPE) technique in mixed micellar medium was applied for the extraction and preconcentration of Al in different
samples. For the CPE of Al, an aliquot of 25 ml solution containing appropriate amounts of Al, acetate buffer, morin and
surfactant (Ttriton X-114 + SDSN) were kept in the thermostatic bath at 50 ºC. Thus, two phases were appeared and separation of
these phases was achieved by centrifugation. After cooling in ice-bath, the surfactant-rich phase became viscous and the upper
aqueous phase decanted. The fluorescence intensity of chelate in the micellar phase (after addition of 2.5 ml of ethanol-water
mixture) was measured at 512 nm with the excitation set at 442 nm. RESULTS: The parameters affecting complexation and
phase separation were studied and optimized. Under the optimum experimental conditions, the detection limit of Al for the
preconcentration of 25 ml of solution was 0.52 μg l-1. The calibration graph was linear within a range of 2-200 μg l-1 Al. The
relative standard deviation (RSD) of 5 replicated determinations of 10 μg l-1 of Al was 2.1%. CONCLUSION: The method was
successfully applied to the determination of Al in water samples and parenteral solutions. |