کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
10545092 | 963618 | 2005 | 6 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Determination of selenium in nutritionally relevant foods by graphite furnace atomic absorption spectrometry using arsenic as internal standard
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Determination of selenium in nutritionally relevant foods by graphite furnace atomic absorption spectrometry using arsenic as internal standard Determination of selenium in nutritionally relevant foods by graphite furnace atomic absorption spectrometry using arsenic as internal standard](/preview/png/10545092.png)
چکیده انگلیسی
A method has been developed for the direct determination of Se in nutritionally relevant foods by graphite furnace atomic absorption spectrometry. Tungsten/rhodium carbide coating on the integrated platform of a transversely heated graphite atomizer or W coating with co-injection of Pd(NO3)2 were used as a permanent modifiers. Samples and reference solutions were spiked with 500 μg Lâ1 As and absorbance variations due to changes in experimental conditions were minimized. For 20 μL aqueous analytical solutions delivered into the graphite tube, analytical curves in the 5.0-40 μg Lâ1 with good linear correlation were established. Pyrolysis and atomization temperatures were evaluated using pyrolysis and atomization curves, respectively. The optimized heating program (temperature, ramp time, hold time) of the graphite tube of the Perkin-Elmer SIMAA 6000 atomic absorption spectrometer was: dry steps (110 °C, 5 s, 10 s; 130 °C, 15 s, 15 s); air-assisted pyrolysis step (600 °C, 20 s, 40 s; 20 °C, 1 s, 40 s); pyrolysis step (1300 °C, 10 s, 20 s); atomization step (2100 °C, 0 s, 4 s); clean step (2550 °C, 1 s, 5 s). The method was applied for Se determination in coconut water, coconut milk, soybean milk, cow milk, tomato juice, mango juice, grape juice and drinking water samples and four standard reference materials and results were in agreement at 95% confidence level. The lifetime of the tube was 500 firings and the relative standard deviations of measurements of typical samples containing 25 μgLâ1 Se were 3.0% and 6.0% (n = 12) with and without internal standardization, respectively. The limits of detection were in the 0.35 μg Lâ1-0.7 μg Se Lâ1 range. The accuracy of the proposed method was evaluated by an addition-recovery experiment and all recovered values were in the 98-109% range.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Food Chemistry - Volume 93, Issue 2, November 2005, Pages 355-360
Journal: Food Chemistry - Volume 93, Issue 2, November 2005, Pages 355-360
نویسندگان
Adriana Paiva Oliveira, José Anchieta Gomes Neto, Joaquim Araújo Nóbrega, Paulo Rogério Miranda Correia, Pedro Vitoriano Oliveira,