کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5130987 1490871 2017 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Determination of total cyanide in soil by isotope dilution GC/MS following pentafluorobenzyl derivatization
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
Determination of total cyanide in soil by isotope dilution GC/MS following pentafluorobenzyl derivatization
چکیده انگلیسی


- A cost-effective, fast and simple method for determination of total cyanide in soil is presented.
- A new micro-distillation strategy was developed overcoming the problems of a conventional distillation.
- Negative chemical ionization-mass spectrometer has been exploited to obtain a high sensitivity and specificity.
- High accuracy was attained for the analysis of certified reference materials with quadruple isotope dilution technique.

The high toxicity of cyanide, along with its widespread industrial use, has fuelled interest in the development of analytical methods for its determination in complex matrices. In this study, we propose a novel approach for the measurement of total cyanide in soil samples based on single-step derivatization with pentafluorobenzyl bromide (F5Bn−Br) followed by quantitation with gas chromatography mass spectrometry in negative chemical ionization mode.The reaction between CN− and F5Bn−Br resulted in the identification of several derivatives such as F5Bn−CN, (F5Bn)(F5Ph)CH−CN, and (F5Bn)2(F5Ph)C−CN. The relative proportion between such compounds was dependent on experimental conditions. When a 100 μL aliquot of an alkaline-aqueous extract was reacted with 700 μL of 1.3% F5Bn−Br in acetone, the tri-alkylated derivative was the most abundant. In such conditions a detection limit of 0.5 ng/g of CN− was attained.Soil samples were initially spiked with an alkaline solution of K13C15N internal standard and suspended in 7.5% aqueous NaOH. Determination of total cyanide was achieved by digestion of the alkaline extract with H3PO4 to produce HCN which was then trapped in 0.1% NaOH in a sealed double vial system, followed by reaction with F5Bn−Br. Isotope dilution calibration was chosen for quantitation, and the validity of the novel method was demonstrated by analysis of soil Certified Reference Materials (CRMs) and by spike recovery tests.

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ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Analytica Chimica Acta - Volume 961, 8 April 2017, Pages 74-81
نویسندگان
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