Microextraction Methods for Preconcentration of Aluminium in Urine Samples

Background: Analysis of aluminium (Al) in urine samples is required in management of a number of diseases including patients with renal failure. This work aimed to present dispersive liquid-liquid microextraction (DLLME) and ultrasound-assisted emulsification microextraction (USAEME) methods for the preconcentration of ultra-trace amount of aluminum in human urine prior to its determination by a graphite furnace atomic absorption spectrometry (GFAAS). Methods: The microextraction methods were based on the complex formation of Al3+ with 8-hydroxyquinoline. The effect of various experimental parameters on the efficiencies of the methods and their optimum values were studied. Results: Under the optimal conditions, the limits of detection for USAEME-GFAAS and DLLME-GFAAS were 0.19 and 0.30 ng mL−1, respectively and corresponding relative standard deviations (RSD, n=5) for the determination of 40 ng mL−1 Al3+ were 5.9% and 4.9%. Conclusion: Both methods could be successfully used to the analysis of ultra trace concentrations of Al in urine samples of dialysis patients.