کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
10560974 | 969759 | 2005 | 7 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
On-line electrochemical preconcentration and flame atomic absorption spectrometric determination of manganese in urine samples
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موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
A sensitive and selective method was developed for the determination of traces of manganese in urine using on-line electrochemical preconcentration followed by flame atomic absorption spectrometry detection. A home made flow-through polypropylene cell (4.5 cm long Ã 0.8 cm diameter filled with glass marbles) with an effective inner volume of 0.5 ml containing a working and a counter electrode, both of glassy carbon and a Pt pseudo reference electrode was located in a flow injection manifold specially designed for the purpose of this work. The manganese was deposited from buffer solution of NH3/NH4Cl at pH 9.00 through an oxidizing process at a current of 400 mA during 7 min. A flow of HCl 0.1 mol lâ1 at 4 ml minâ1 through the cell, chemically dissolved the deposit. A small portion (15 μl) of the concentrate was introduced in a continuously flowing system by means of a timing device and was then carried to the detector for the manganese quantification. All electrochemical and spectroscopic variables as well as possible interferences in both systems were systematically studied. The relative standard deviations for ten consecutive measurements of manganese solutions of 2.0 and 20 μg lâ1 were of 2.3 and 1.5%, respectively, while for a sample processed five times was less then 5%. The accuracy of the developed procedure was evaluated by adding known amounts of manganese standard to urine samples and following the whole procedure. Recoveries within the range 97.2-102.8% were obtained. To further prove the accuracy, a Seronorm Trace Elements in Urine, Batch 403125 sample with a reported concentration of 13 μg Mn lâ1 was also analyzed. The experimental value obtained was of 12.7 ± 0.1 μg lâ1, which does not differ significantly from the reported amount (p < 0.05). A preconcentration factor of 40, a linear range between 0.015 and 60 μg lâ1 and a limit of detection of 15 ng lâ1 permitted the determination of manganese in real urine samples from non-exposed subjects in the range 0.5-2.8 μg lâ1.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Talanta - Volume 68, Issue 2, 15 December 2005, Pages 219-225
Journal: Talanta - Volume 68, Issue 2, 15 December 2005, Pages 219-225
نویسندگان
Marcela Burguera, José Luis Burguera, Darveris Rivas, Carlos Rondón, Pablo Carrero, Oscar M. Alarcón, Yaneira Petit de Peña, Maria R. Brunetto, Máximo Gallignani, Olga P. Márquez, Jairo Márquez,