Preconcentration of 1-(2-pyridylazo)—2-naphthol—iron(III)-capriquat on a membrane filter, and third-derivative spectrophotometric determination of iron(III)
1994; Elsevier BV; Volume: 41; Issue: 2 Linguagem: Inglês
10.1016/0039-9140(94)80116-9
ISSN1873-3573
Autores Tópico(s)Analytical Chemistry and Sensors
ResumoIron(III) was preconcentrated by collection on an organic solvent—soluble membrane filter (nitrocellulose (NC)) of the iron(III)–1-(2-pyridylazo)—2-naphthol (PAN) complex in the presence of capriquat as an oily quaternary ammonium salt. Third-derivative spectrophotometry was used for measurement of the third-derivative distance (d3A/dλ3) between λ1 = 520 nm and λ2 = 590 nm or λ3 = 660 nm and λ4 = 724 nm of the iron(III)—PAN—capriquat complex or PAN—capriquat in dimethylsulfoxide (DMSO) following preconcentration. The calibration curve was linear in the range of 1–10 μg iron(III)/5.0 ml DMSO solution. The proposed method was about five-fold more sensitive and more selective than using zero-order spectrophotometry.
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