scholarly journals Determination of Captafol, Cyhexatin, 1-Naphthylacetic Acid and Quintozene in Apple, Japanese Pear and Melon by Simultaneous Extraction.

2003 ◽  
Vol 44 (2) ◽  
pp. 126-131 ◽  
Author(s):  
Toshihiro NAGAYAMA ◽  
Ichiro TAKANO ◽  
Maki KOBAYASHI ◽  
Yasuhiro TAMURA ◽  
Sanae TOMIZAWA ◽  
...  
Keyword(s):  
Japanese Pear ◽  
Simultaneous Extraction ◽  
Naphthylacetic Acid

scholarly journals Magnetic Solid-Phase Extraction using Ionic Liquid-Modified Magnetic Nanoparticles for The Simultaneous Extraction of Cadmium and Lead in Milk Samples; Evaluation of Measurement Uncertainty

2021 ◽  
Vol 65 (4) ◽  
Author(s):  
Sara Khodadadi ◽  
Elaheh Konoz ◽  
Ali Ezabadi ◽  
Ali Niazi
Keyword(s):  
Ionic Liquid ◽  
Magnetic Nanoparticles ◽  
Solid Phase ◽  
Magnetic Solid Phase Extraction ◽  
Phase Extraction ◽  
Simultaneous Extraction ◽  
Milk Samples ◽  
Magnetic Solid ◽  
Modified Magnetic Nanoparticles

Abstract. In the present study, a new, sensitive, and rapid method was developed for extraction and determination of the trace amounts of Pb (II) and Cd (II) ions in milk samples through magnetic solid-phase extraction using DABCO based-ionic liquid-modified magnetic nanoparticles (Fe3O4/[DABCO-PDO]Cl NPs). Herein, Pb (II) and Cd (II) contents were quantified with flame atomic absorption spectroscopy (FAAS). The effect of different empirical parameters (such as sample pH, adsorbent amount, type and amount of the elution, extraction and desorption times, and the ligand concentration) was evaluated and optimized for simultaneous extraction and pre-concentration Pb (II) and Cd (II) ions. The calibration curve was linear under the optimum condition in the concentration range of 0.4-200 µgL-1 for Cd, and 0.5-120 µgL-1 for Pb, respectively. The pre-concentration factor was 67, with the detection limit of 0.09 and 0.07 µgL-1 for Pb and Cd, respectively. The relative standard deviation values (RSD %) of the proposed method were lower than 2.6 %. The developed method was successfully used to determine lead and cadmium content in milk samples. The information obtained from the method validation has been used to estimate the expanded uncertainty for the determination of Pb (II) and Cd (II) at trace levels in commercial milks.   Resumen. En este trabajo, se ha desarrollado un nuevo, sensible y rápido procedimiento para la extracción y determinación de iones Pb(II) y Cd(II) a nivel de trazas en leche, mediante extracción en fase sólida utilizando nanopartículas magnéticas modificadas con líquido iónico basado en DABCO (Fe3O4/[DABCO-PDO]Cl NPs). La determinación de ambos metales se llevó a cabo por espectrometría de absorción atómica con atomización en llama. Se ha evaluado el efecto de diferentes parámetros empíricos (tales como pH, cantidad de adsorbente, tipo y cantidad de solvente de elución, tiempo de extracción y desorción, y concentración del ligando); estos parametros fueron optimizados enfocándose en la extracción y preconcentración simultanea de ambos iones. Empleando las condiciones establecidas, se obtuvo buena linealidad de las curvas de calibración en el intervalo de concentraciones 0.4-200 µgL-1 para Cd, y 0.5-120 µgL-1 para Pb, respectivamente. Se logró el factor de preconcentración 67, con los límites de detección 0.09 y 0.07 µgL-1 para Pb y Cd, respectivamente. Los valores de desviación estandar relativa (RSD %) en el procedimiento propuesto no sobrepasaron 2.6 %. En el análisis de leche, se obtuvieron resultados satisfactorios. Los datos obtenidos en etapa de validación se utilizaron para estimar la incertidumbre expandida en la determinación de Pb y Cd a nivel de trazas en leche.

EFFECT OF EDTA AND DTPA ON AVAILABLE-P EXTRACTION WITH THE KELOWNA MULTIPLE ELEMENT EXTRACTANT

1989 ◽  
Vol 69 (2) ◽  
pp. 191-197
Author(s):  
W. VAN LIEROP
Keyword(s):  
Key Words ◽  
Reference Values ◽  
Calcareous Soils ◽  
Acid Soils ◽  
Available P ◽  
Complexing Agents ◽  
Simultaneous Extraction ◽  
Soil P ◽  
Regression Techniques

The objective of this study was to determine the effect of adding either 0.001M EDTA or 0.005M DTPA on the amount of P removed from acid and calcareous soils by the Kelowna and 0.25M HO Ac extractants. These complexing agents were studied for possible simultaneous extraction and determination of available Zn. To achieve that end, P-concentrations removed by these solutions from a group of acid, calcareous, and combined soils were compared against reference values obtained with 0.5M NaHCO3 (Olsen et al.) and the Kelowna extractant (0.25M HOAc + 0.015M NH4F) by means of graphing, correlation and regression techniques. Of the 80 soils studied, 40 were acid with pH (H2O) values ranging from 4.2 to 6.9 and the remainder having higher values up to 9.3. Results indicated that additions of either 0.001M EDTA or 0.005M DTPA to the Kelowna solution increased average extracted P concentrations by about 20 and 60%, respectively. Values removed by either of the new KEDTA and KDTPA solutions were closely related to those extracted with 0.5M NaHCO3 and Kelowna solutions on acid and calcareous soils (r values ≥ 0.96**). As EDTA and DTPA increased extracted soil P, these were added at 0.001 and 0.005M as NH4 preparations to 0.25M HOAc (AADTPA & AAEDTA; without fluoride), respectively, for determining whether these complexing agents could supplant F for P extraction. These solutions removed proportionally related amounts (r ≈ 0.94**) of P from calcareous, compared to the Kelowna and 0.5M NaHCO3 solutions, but relationships were less precise for acid soils (r ≈ 0.76**). These results suggest that the AADTPA or AAEDTA solution should be evaluated further before adoption for routine P determination in multiple element extractions. Key words: Mehlich in, acid soils, calcareous soils

Inclusion of 1-Naphthylacetic Acid and 2-(1-Naphthyl)acetamide into Three Typical Multiresidue Methods for LC/MS/MS Analysis of Tomatoes and Zucchini

2012 ◽  
Vol 95 (5) ◽  
pp. 1520-1527 ◽  
Author(s):  
Ana Lozano ◽  
Andrés Pérez-Parada ◽  
Horacio Heinzen ◽  
Amadeo R Fernández-Alba
Keyword(s):  
Fruits And Vegetables ◽  
Matrix Effects ◽  
Multiple Reaction Monitoring ◽  
Application Rates ◽  
Directorate General ◽  
Maximum Residue Levels ◽  
Repeatability And Reproducibility ◽  
Naphthylacetic Acid ◽  
Negative Electrospray Ionization

Abstract In spite of high plant growth regulator application rates, little has been reported in the literature on determination of their residues in fruits and vegetables. This would be useful in monitoring good manufacturing practices and overall safety through the enforcement of maximum residue levels (MRLs). The present work describes method validation for the determination of 1-naphthylacetic acid (NAA) and 2(1-naphthyl)acetamide (NAAm) in tomato and zucchini using the mini-Luke, ethyl acetate (EtOAc) and acetate-buffered quick, easy, cheap, effective, rugged, and safe (QuEChERS) methods. Samples were spiked at two different levels: 50 and 100 μg/kg for NAA and 20 and 100 μg/kg for NAAm. These compounds were analyzed within the same chromatographic run with LC coupled to triple quadrupole MS (LC/(QqQ)MS/MS) in positive and negative electrospray ionization [ESI(+) and ESI(–)] modes for NAAm and NAA, respectively. For analyte confirmation, LC/ESI(-)QTOF-MS was also investigated given that NAA has only one multiple reaction monitoring transition (185.1→140.9 m/z). These three common methods were used to determine linearity, recoveries, precision (RSD), matrix effects, repeatability, and reproducibility (n = 5) for the selected matrixes. In terms of the Directorate-General for Health and Consumers (DG-SANCO) guidelines, only insignificant differences were found for the multiresidue methods tested, regardless of the commodity. Matrix-matched calibration was used, and LODs were below 10.1 μg/kg for NAA and 6.0 μg/kg for NAAm, which were lower than the MRLs established in current European Union legislation for these compounds. Obtained recoveries for NAA ranged from 87 to 107% with RSD values below 10% for mini-Luke, 83 to 107% with RSD <11% for EtOAc, and 76 to 85% with RSD ≤7% for QuEChERS. NAAm recoveries ranged from 74 to 102% with RSD ≤ 15% for mini-Luke, 76 to 97% with RSD <4% for EtOAc, and 76 to 93% with RSD ≤ 5% for QuEChERS. The linearity of the response over two orders of magnitude was demonstrated (r2 > 0.996) for all methods used. Good repeatability and reproducibility in terms of RSD were obtained (11.3–17.8%) for these analytical methods. The results were acceptable within the studied ranges for both analytes in all methods. As these multiresidue methods are used at the present time in many laboratories, this survey indicates that these analytes should be included in their monitoring scope.

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