کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1243118 | 969654 | 2008 | 4 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Cloud point extraction for ultra-trace Cd determination in microwave-digested biological samples by ETAAS
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Cloud point extraction for ultra-trace Cd determination in microwave-digested biological samples by ETAAS Cloud point extraction for ultra-trace Cd determination in microwave-digested biological samples by ETAAS](/preview/png/1243118.png)
چکیده انگلیسی
Cloud point extraction (CPE) has been used for the preconcentration of cadmium, after the formation of a complex with 2-(5-bromo-2-pyridylazo)-5-(diethylamino)-phenol (5-Br-PADAP), and further determination by graphite furnace atomic absorption spectrometry (ETAAS) using polyethyleneglicolmono-p-nonyphenylether (PONPE 7.5) as surfactant. The chemical variables that affect the cloud point extraction were optimized. The separation of the two phases was easily accomplished by cooling the mixture in order to make more viscous the surfactant-rich phase. In order to establish the optimum conditions for the determination of Cd by ETAAS, Pd + Mg, Pt, Ir, Rh and Ru were studied as chemical modifiers. The best thermal stabilization was obtained with Pd + Mg, with a maximum pyrolysis temperature of 1100 °C. Under the optimum conditions i.e., pH 9.0, [5-Br-PADAP] = 2.0 Ã 10â5 mol Lâ1, [PONPE 7.5] = 0.02% (w/v), an enhancement factor of 22-fold was reached. The lower limit of detection (LOD) obtained under the optimal conditions was 0.008 μg Lâ1. The precision for 10 replicate determinations at 0.2 μg Lâ1 Cd was 3.5% relative standard deviation (R.S.D.). The calibration graph using the preconcentration method was linear with a correlation coefficient of 0.9984 at levels close to the detection limit up to at least 1.0 μg Lâ1. The method was successfully applied to the determination of cadmium in urine samples and in a water standard reference material.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Talanta - Volume 77, Issue 2, 15 December 2008, Pages 663-666
Journal: Talanta - Volume 77, Issue 2, 15 December 2008, Pages 663-666
نویسندگان
Pedro R. Aranda, Raúl A. Gil, Susana Moyano, Irma De Vito, Luis D. Martinez,