Determination of trace aluminum in biological and water samples by cloud point extraction preconcentration and graphite furnace atomic absorption spectrometry detection.

Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, PR China.
Journal of Hazardous Materials (Impact Factor: 3.93). 07/2008; 154(1-3):1127-32. DOI: 10.1016/j.jhazmat.2007.11.018
Source: PubMed

ABSTRACT A cloud point extraction (CPE) method for the preconcentration of trace aluminum prior to its determination by graphite furnace atomic absorption spectrometry (GFAAS) has been developed. The CPE method is based on the complex of Al(III) with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP), and then entrapped in non-ionic surfactant Triton X-114. PMBP was used not only as chelating reagent in CPE preconcentration, but also as chemical modifier in GFAAS determination. The main factors affecting CPE efficiency, such as pH of sample solution, concentration of PMBP and Triton X-114, equilibration temperature and time, were investigated in detail. An enrichment factor of 37 was obtained for the preconcentration of Al(III) with 10 mL solution. Under the optimal conditions, the detection limit of this method for Al(III) is 0.09 ng mL(-1), and the relative standard deviation is 4.7% at 10 ng mL(-1) Al(III) level (n=7). The proposed method has been applied for determination of trace amount of aluminum in biological and water samples with satisfactory results.

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    ABSTRACT: In this study, cloud point extraction was used for the preconcentration of Al(3+) ion after the complex formation with 1,4-dihydroxy-9,10-anthraquinone (Quinizarin [QUIN]), and subsequent analysis by spectrophotometeric method, using Triton X-114 as surfactant. The optimal extraction and reaction conditions were studied (i.e., pH = 5.5, 0.1 mM QUIN, Triton X-114 = 0.1 % (w/v)), and the analytical characteristics of the method (e.g., limit of detection, linear range, preconcentration, and enrichment factors) were obtained. Linearity was obeyed in the range of 3.33-166.67 ng ml(-1) of Al(3+) ion. The detection limit of the method was 2.09 ng ml(-1) for Al(3+) ion. The interference effect of some anions and cations was also tested. The method was applied to determine Al(3+) ion in water samples.
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Jun 6, 2014

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