6533b871fe1ef96bd12d1b45
RESEARCH PRODUCT
On-line bi-directional electrostacking for As speciation/preconcentration using electrothermal atomic absorption spectrometry.
Marco Aurélio Zezzi ArrudaLuciana Melo CoelhoNívia M. M. CoelhoMiguel De La Guardiasubject
Detection limitmedia_common.quotation_subjectAnalytical chemistrychemistry.chemical_elementAnalytical Chemistrylaw.inventionBoric acidchemistry.chemical_compoundSpeciationPotassium permanganateMineral waterchemistrySodium hydroxidelawAtomic absorption spectroscopyArsenicmedia_commondescription
A method using bi-directional electrostacking (BDES) in a flow system is presented for As preconcentration and speciation analysis. Some parameters such as electrostacking time and applied voltage, support buffers and their concentrations were investigated. Boric acid plus sodium hydroxide at 0.1mol/l concentration was selected as support buffer to improve the pre-concentration factor (PF) for As(V). An analytical range from 2.0 to 50.0mugl(-1), and 0.35mugl(-1) as limit of detection, when applied 750V for 20min, were achieved. Under these conditions, a pre-concentration factor of 4.8 was obtained. The proposed method was applied to determine As(V) in mineral water and natural water samples (river, fountain and gold mine) from Ouro Preto city. Recoveries from 93.5 to 106.4% were achieved at 10mugl(-1) added As level (R.S.D.s between 3 and 7%). Potassium permanganate (10mgl(-1)) was used for oxidising As species in order to determine total As, being established the concentration of As(III) from the difference between total As and As(V).
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2006-01-09 | Talanta |