کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1235919 1495287 2007 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Determination of trace selenium by solid substrate-room temperature phosphorescence enhancing method based on potassium chlorate oxidizing phenyl hydrazine-1,2-dihydroxynaphthalene-3,6-disulfonic acid system
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
Determination of trace selenium by solid substrate-room temperature phosphorescence enhancing method based on potassium chlorate oxidizing phenyl hydrazine-1,2-dihydroxynaphthalene-3,6-disulfonic acid system
چکیده انگلیسی
A new method for the determination of trace selenium based on solid substrate-room temperature phosphorimetry (SS-RTP) has been established. This method was based on the fact that in HCl-KCl buffer solution, potassium chlorate could oxidize phenyl hydrazine to form chloridize diazo-ion after being heated at 100 °C for 20 min, and then the diazo-ion reacted with 1,2-dihydroxynaphthalene-3,6-disulfonic acid to form red azo-compound which could emit strong room temperature phosphorescence (RTP) signal on filter paper. Selenium could catalyze potassium chlorate oxidizing the reaction between phenyl hydrazine and 1,2-dihydroxynaphthalene-3,6-disulfonic acid, which caused the sharp enhancement of SS-RTP. Under the optimum condition, the relationship between the phosphorescence emission intensity (ΔIp) and the content of selenium obeyed Beer's law when the concentration of selenium is within the range of 1.60-320 fg spot−1 (or 0.0040-0.80 ng ml−1 with a sample volume of 0.4 μl). The regression equation of working curve can be expressed as ΔIp = 13.12 + 0.4839CSe(IV) (fg spot−1) (n = 6), with correlation coefficient r = 0.9991 and a detection limit of 0.28 fg spot−1 (corresponding to a concentration range of 7.0 × 10−13 g ml−1 Se(IV), n = 11). After 11-fold measurement, R.S.D. were 2.8 and 3.5% for the samples containing 0.0040 and 0.80 ng ml−1 of Se(IV), respectively. This accurate and sensitive method with good repeatability has been successfully applied to the determination of trace selenium in Chinese wolfberry and egg yolk with satisfactory results. The mechanism of the enhancement of phosphorescence was also discussed.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy - Volume 66, Issues 4–5, April 2007, Pages 1194-1198
نویسندگان
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