Iron speciation in natural waters by sequential injection analysis with a hexadentate 3-hydroxy-4-pyridinone chelator as chromogenic agent

TALANTA

卷:148

Article

Miranda, Joana L. A.¹  Mesquita, Raquel B. R.^1,2  Nunes, Ana³  Rangel, Maria³  Rangel, Antonio O. S. S.¹ 

[1] Univ Catolica Portuguesa Porto, Escola Super & Biotecnol, CBQF Ctr Biotecnol & Quim Fina, Lab Assoc, P-4202401 Porto, Portugal

[2] Univ Porto, Lab Hidrobiol, Inst Ciencias Biomed Abel Salazar ICBAS, P-4050313 Porto, Portugal

[3] Inst Ciencias Biomed Abel Salazar ICBAS, REQUIMTE, P-4050313 Porto, Portugal

关键词: Hexadentate 3,4-hydroxypiridinone ligand;    Iron speciation;    Solid phase extraction;    Fresh and saline water samples;   

DOI  :  10.1016/j.talanta.2015.05.062

来源: Elsevier

【 摘 要 】

A sequential injection method for iron speciation in various types of natural waters was developed using a synthesised hexadentate 3-hydroxy-4-pyridinone chelator (CP256). The denticity of the ligand that allow formation of the corresponding iron(III) complex in a 1:1 stoichiometry proved to be highly advantageous, in comparison with parent bidentate, hydroxy-4-piridinone chelators, with a two fold increase of reaction sensitivity and over 65% decrease of the LOD. A solid phase extraction approach was employed to attain matrix elimination, facilitating iron(III) determination and application to high salinity waters. The combination with the total iron determination obtained by the direct reaction of the ligand resulted in iron speciation. Two detection spectrophotometric cells were tested, a conventional flow cell (CFC) and a liquid waveguide capillary cell (LWCC). The dynamic concentration ranges were 0.1-2 mg/L with the CFC detection and 0.005-0.1 mg/L with the LWCC, with limit of detection of 30 mu g/L and 6 mu g/L, respectively. The developed method was successfully applied to a variety of natural waters. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

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