Separation/preconcentration methods for the determination of aluminum in dialysate solution and scalp hair samples of kidney failure patients.

A new method is reported for the separation of aluminum ions (Al(3+)) from interfering cations in pharmaceutical and biological samples through solid-phase extraction (SPE) using 2-methyl-8-hydroxyquinoline (8-hydroxyquinaldine) on activated silica. While separated Al(3+) was preconcentrated by cloud point extraction (CPE) using 3,5,7,2'-4'-pentahydroxyflavone (morin) as complexing reagent, the resulting complex was entrapped in nonionic surfactant (Triton X-114) as prior step to its determination by spectrofluorimetry (SPF). The validity of separation/preconcentration of Al(3+) was checked by certified reference material of human hair and standard addition method. The chemical variables affecting the analytical performance of the separation/preconcentration methods were studied and optimized. The enrichment factor and detection limit of Al(3+) for the preconcentration of 10 ml of dialysate solution and acid-digested samples of scalp hair samples were found to be 25 and 0.34 μg/L, respectively. The relative standard deviation for six replicates of standard containing 20 μg/L of Al(3+) was <10%. In all DS, the concentration of Al was >10 μg/L. The level of Al in scalp hair samples of kidney failure patients was higher than healthy controls.