Determination of total arsenic and arsenic(III) in phosphate fertilizers by hydride generation atomic absorption spectrometry after ultrasound-assisted extraction based on a control acid media
| Autor: | Helen C. Rezende, Nívia M. M. Coelho |
|---|---|
| Rok vydání: | 2014 |
| Předmět: |
Central composite design
Inorganic chemistry chemistry.chemical_element Analytical Chemistry law.invention Arsenic Phosphates chemistry.chemical_compound Sonication law Limit of Detection Environmental Chemistry Fertilizers Pharmacology Detection limit Hydride Spectrophotometry Atomic Extraction (chemistry) Certified reference materials Thiourea chemistry Atomic absorption spectroscopy Agronomy and Crop Science Food Science Nuclear chemistry |
| Zdroj: | Journal of AOAC International. 97(3) |
| ISSN: | 1060-3271 |
| Popis: | An ultrasound-assisted extraction procedure was developed for determination of inorganic arsenic (As) in phosphate fertilizer by hydride generation atomic absorption spectrometry. The variables that affect the hydride generation step were optimized, including the reducer, acid, sample flow rate, and concentrations of the acid and reducer. The determination of As(lll) was performed through the simple control of solution pH with a 0.5 M citric acid-sodium citrate buffer solution at pH 4.5, and total As was determined after a pre-reduction reaction with 1.0% (w/v) thiourea. Ultrasound-assisted acid extraction was performed, and the parameters sonication time and acid and Triton X-114 concentrations were optimized using a 23 factorial design and central composite design. LODs for As(lll) and total As were 0.029 and 0.022 microg/L, respectively. The accuracy of the method was confirmed with certified reference materials. The method was successfully applied in the determination of inorganic As in phosphate fertilizer samples. |
| Databáze: | OpenAIRE |
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