0000000000441457

AUTHOR

Luciana Melo Coelho

Food Chemistry: Food quality and new analytical approaches

Peer Reviewed

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Determination of arsenic compounds in beverages by high-performance liquid chromatography-inductively coupled plasma mass spectrometry.

Arsenic compounds including arsenous acid (As(III)), arsenic acid (As(V)), dimethylarsinic acid (DMA) and monomethylarsonic acid (MMA) were separated by high-performance liquid chromatography (HPLC) and detected by inductively coupled plasma mass spectrometry (ICP-MS). A Hamilton PRX-100 anionic-exchange column and a pH 8.5 K(2)HPO(4)/KH(2)PO(4) 5.0x10(-3)molL(-1) mobile phase were used to achieve arsenic speciation. The separation of arsenic species provided peaks of As(III) at 2.75min, DMA at 3.33min, MMA at 5.17min and As(V) at 12.5min. The detection limits, defined as three times the standard deviation of the lowest standard measurements, were found to be 0.2, 0.2, 0.3 and 0.5ngmL(-1) f…

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On-line bi-directional electrostacking for As speciation/preconcentration using electrothermal atomic absorption spectrometry.

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…

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