Fatemeh Nourpishe; Ali Asghar Amiri; Ali Sheibani; Masoud Reza Shishehbore
Abstract
In this study, a simple and sensitive method was developed for pre-concentration of spirotetramat (SPT) using the ionic liquid-based dispersive liquid-liquid microextraction. After extracting of SPT into 1-butyl-3-methylimidazolium hexafluorophosphate (ionic liquid), the insecticide was injected into ...
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In this study, a simple and sensitive method was developed for pre-concentration of spirotetramat (SPT) using the ionic liquid-based dispersive liquid-liquid microextraction. After extracting of SPT into 1-butyl-3-methylimidazolium hexafluorophosphate (ionic liquid), the insecticide was injected into HPLC system for determining. Under the optimum conditions, the developed method provided a linearity in the range of 0.05–2.0 µg mL-1 with R2= 0.9987, and also enrichment factor was 250. The detection limit and relative standard deviation of the developed method were 0.01 µg mL-1 and 2.7%, respectively. The proposed method was successfully applied to the pre-concentration and determination of SPT in spiked water samples with mean recoveries 94.0-96.0%.
Maryam Ghanbarian; Farzad Etemadi; Ali Mostafavi; Moslem Afzali
Volume 1, Issue 1 , March 2014, , Pages 53-57
Abstract
In this work, a selective method for separation and preconcentration of nickel ions at trace level on modified multiwalled carbon nanotubes columns and determination by flame atomic absorption spectrometry (FAAS) has been developed. Multiwalled carbon nanotubes were oxidized with concentrated HNO3 and ...
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In this work, a selective method for separation and preconcentration of nickel ions at trace level on modified multiwalled carbon nanotubes columns and determination by flame atomic absorption spectrometry (FAAS) has been developed. Multiwalled carbon nanotubes were oxidized with concentrated HNO3 and then modified with loading 1-(2-pyridylazo)-2-naphtol. The sorption of Ni(II) ions was quantitative in the pH =9. Elution of the adsorbed nickel was carried out with 5.0 mL of 0.1 mol L−1 HNO3. The amount of eluted nickel was measured using flame atomic absorption spectrometry. Factors influencing sorption and desorption of Ni(II) ions were investigated, including the sample pH, flow rates of sample and eluent solution, eluent type, breakthrough volume and interference ions. The relative standard deviation of the method was ±0.57% (n=8) and the limit of detection was 2.04 g mL−1 (3σb/m, n=8). The method was applied to the determination of Ni(II) in water samples and standard alloy (NKK. NO. 920, Aluminum Alloy).