scholarly journals Rapid separation and extraction of radioactive analytes onto filters and surfaces

2011 ◽  
Vol 1 (1) ◽  
pp. 194-200
Author(s):  
E. R. Gonzáles ◽  
A. L. Klingensmith ◽  
D. S. Peterson
Keyword(s):  
Sample Preparation ◽  
Alpha Spectrometry ◽  
Extraction Efficiency ◽  
Filter Material ◽  
Selective Extraction ◽  
Rapid Separation ◽  
Wet Chemical ◽  
Peak Widths ◽  
Additional Sample ◽  
Polymer Ligand

AbstractThis paper presents a radiochemical procedure that combines radiochemical sample preparation and analyte separation to provide a rapid sample preparation method. Extractive ligands are prepared in a polymer matrix. This system can be immobilized on a surface or on a filter. Filters allow rapid sample uptake due to the movement of the analyte through the filter material. These approaches offer fast uptake kinetics, high material loading, and good selectivity. These systems have been demonstrated for the rapid extraction of plutonium and americium from solution and their subsequent analysis by alpha spectrometry, with no additional sample preparation required, thus eliminating extensive wet chemical processes that would otherwise be necessary. We have evaluated the extraction efficiency that can be obtained and have shown that these systems can provide for alpha spectrometry peak widths near what can be obtained using traditional techniques such as electroplating. We have also demonstrated Polymer Ligand Films (PLFs) for the selective extraction of plutonium from a solution prepared from a soil digest.

Efficient trace-scale extraction method of reactor produced 199Au adequate for nuclear medicine applications

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mohamed F. Attallah ◽  
Ahmed M. Shahr El-Din ◽  
Mohamed A. Gizawy ◽  
Amal M. I. Ali
Keyword(s):  
Aqueous Media ◽  
Selective Extraction ◽  
Extraction Process ◽  
High Yield ◽  
High Recovery ◽  
Rapid Separation ◽  
Efficient Separation ◽  
Liquid Liquid Extraction ◽  
Cyanex 302 ◽  
Cyanex 923

Abstract Production of no carrier-added (NCA) 199Au through natPt(n, γ) reaction and subsequent purification using liquid-liquid extraction from other radioisotopes is studied in the context of theranostic application. Comparative separation of NCA 199Au after dissolution of activated Pt target using three Cyanex compounds (Cyanex-272, Cyanex-302 and Cyanex-923) is evaluated. The extraction process is optimized in terms of the type of extractant, the concentration of extractant, extraction time and aqueous media (HNO3, NH4OH). Among these extractants, the Cynaex-923 is efficient and promising for rapid separation and production of NCA 199Au from HNO3 by high extraction %. Selective extraction of 199Au from other Pt and Ir radioisotopes is observed. High recovery of 199Au was obtained in the case of Cyanex-923 using 0.05 M thiourea dissolved in HCl or 2 M NaOH. Our results find the Cyanex-923 as a promising extractant for efficient separation of 199Au from irradiated Pt target with high yield (99%).

Determination of Free Solanesol Levels in Cigarette Filters by Liquid Chromatography–Mass Spectrometry

2021 ◽  
Author(s):  
Roberto Bravo Cardenas ◽  
Phuong Ngac ◽  
Clifford Watson ◽  
Liza Valentin-Blasini
Keyword(s):  
Liquid Chromatography ◽  
Sample Preparation ◽  
Tobacco Smoke ◽  
Limit Of Detection ◽  
Internal Standard ◽  
Filter Material ◽  
Previous Method ◽  
Tobacco Smoke Exposure ◽  
Triple Quadrupole Mass Spectrometer ◽  
Cigarette Butts

Abstract Solanesol, a naturally occurring constituent of tobacco, has been utilized as a good marker for environmental tobacco smoke particulate and as a noninvasive predictor of mainstream cigarette smoke tar and nicotine intake under naturalistic smoking conditions. A fast and accurate method for measuring free solanesol to assess tobacco smoke exposure is highly desirable. We have developed and validated a new environmentally friendly, high-throughput method for measuring solanesol content in discarded cigarette filter butts. The solanesol deposited in the used filters can be correlated with mainstream smoke deliveries of nicotine and total particle matter to estimate constituent delivery to smokers. A portion of filter material is removed from cigarette butts after machine smoking, spiked with internal standard solution, extracted and quantitatively analyzed using reverse-phase liquid chromatography coupled to a triple-quadrupole mass spectrometer. The new method incorporates a 48-well plate format for automated sample preparation that reduces sample preparation time and solvent use and increases sample throughput 10-fold compared to our previous method. Accuracy and precision were evaluated by spiking known amounts of solanesol on both clean and smoked cigarette butts. Recoveries exceeded 93% at both low and high spiking levels. Linear solanesol calibration curves ranged from 1.9 to 367 µg/butt with a 0.05 µg/butt limit of detection.

scholarly journals Tantalum and Niobium Selective Extraction by Alkyl-Acetophenone

Metals ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 654 ◽  
Author(s):  
Moussa Toure ◽  
Guilhem Arrachart ◽  
Jean Duhamet ◽  
Stephane Pellet-Rostaing
Keyword(s):  
Extraction Efficiency ◽  
Methyl Isobutyl Ketone ◽  
Selective Extraction ◽  
Extraction Process ◽  
Liquid Extraction ◽  
Methyl Isobutyl ◽  
Isobutyl Ketone ◽  
Waste Solution ◽  
Liquid Liquid Extraction ◽  
D Values

A study has been carried out on Ta and Nb recovery by a liquid-liquid extraction process using 4-methylacetophenone (4-MAcPh) as the organic phase. The 4-MAcPh was compared to methyl isobutyl ketone (MIBK) with respect to extraction efficiencies (D values) at different concentrations of H2SO4 in the aqueous phase. The results showed a similar extraction of Nb for both solvents. However, for Ta, extraction efficiency is increased by a factor of 1.3 for 4-MAcPh. In addition, the MIBK solubilized completely after 6 mol∙L−1 of H2SO4 against only a loss of 0.14–4% for 4-MAcPh between 6 and 9 mol∙L−1 of H2SO4. The potential of 4-MAcPh has also been studied to selectively recover Ta from a model capacitor waste solution. The results showed a selectivity for Ta in the presence of impurities such as Ag, Fe, Ni and Mn. The 4-MAcPh also presents the advantage of having physicochemical properties adapted to its use in liquid-liquid extraction technologies such as mixer-settlers.

scholarly journals Recent Advances in Affinity MOF-Based Sorbents with Sample Preparation Purposes

Molecules ◽  
2020 ◽  
Vol 25 (18) ◽  
pp. 4216
Author(s):  
Héctor Martínez Pérez-Cejuela ◽  
José Manuel Herrero-Martínez ◽  
Ernesto F. Simó-Alfonso
Keyword(s):  
Amino Acids ◽  
Sample Preparation ◽  
Metal Organic Frameworks ◽  
Selective Extraction ◽  
Real Samples ◽  
Recent Advances ◽  
Different Types ◽  
Metal Organic

This review summarizes the recent advances concerning metal–organic frameworks (MOFs) modified with several biomolecules (e.g., amino acids, nucleobases, proteins, antibodies, aptamers, etc.) as ligands to prepare affinity-based sorbents for application in the sample preparation field. The preparation and incorporation strategies of these MOF-based affinity materials were described. Additionally, the different types of ligands that can be employed for the synthesis of these biocomposites and their application as sorbents for the selective extraction of molecules and clean-up of complex real samples is reported. The most important features of the developed biocomposites will be discussed throughout the text in different sections, and several examples will be also commented on in detail.

High-Throughput Analytical Techniques for Determination of Residues of 653 Multiclass Pesticides and Chemical Pollutants in Tea, Part II: Comparative Study of Extraction Efficiencies of Three Sample Preparation Techniques

2013 ◽  
Vol 96 (2) ◽  
pp. 432-440 ◽  
Author(s):  
Chun-Lin Fan ◽  
Qiao-Ying Chang ◽  
Guo-Fang Pang ◽  
Zeng-Yin Li ◽  
Jian Kang ◽  
...  
Keyword(s):  
Sample Preparation ◽  
Green Tea ◽  
High Speed ◽  
Extraction Efficiency ◽  
Preparation Technique ◽  
Test Results ◽  
Chemical Pollutants ◽  
Chemical Pollutant ◽  
Three Stages

Abstract This paper reports a study of the extraction efficiency for the multiresidue pesticides and chemical pollutants in tea with three methods over three stages. Method 1 adopts the Pang et al. approach: the targets were extracted with 1% acetic acid in acetonitrile and cleaned up with a Cleanert TPT SPE cartridge; Method 2 adopts the QuEChERS approach: the targets were cleaned up dispersively with graphitized carbon and primary-secondary amine (PSA) sorbent; Method 3 adopts the relatively commonly used approach of hydration for solid samples, with tea hydrated before being extracted through salting out with acetonitrile and the cleanup procedures identical to those of Method 1. The three stages comprised two phases of comparative tests on spike recoveries of 201 pesticides and chemical pollutants from different teas and a third phase on determination of the content of the 201 pesticides and chemical pollutants from aged tea samples. In stages I and II, test results of the spike recoveries of 201 pesticides and chemical pollutants demonstrated that 91.4% of the pesticide and chemical pollutant recoveries fell within the range of 70–110%, and 93.2% of the pesticides and chemical pollutants had RSD < 15%, with no marked difference obtained by Method 1 and Method 2 regardless of whether it was green tea or woolong tea, or GC/MS or GC/MS/MS was used for analysis. For pigment removal, Method 1 was superior to Method 2; in terms of easy operation, Method 2 outweighed Method 1. However, Method 3 obtained relatively low recoveries, with 94% of pesticide and chemical pollutant recoveries less than 70%, which proved that Method 3 was not applicable to the determination of multiresidue pesticides and chemical pollutants in tea. Stage III made a comparison of Method 1 and Method 2 for the extraction efficiency of pesticides and chemical pollutants in 165-day-aged samples of green and woolong tea. Test results showed that 94% of the pesticide and chemical pollutant content in the aged tea samples was recovered with Method 1, more than 10% higher than with Method 2 (30–50% higher on average). For green tea, 193 (GC/MS/MS) and 197 (GC/MS) pesticides and chemical pollutants accounted for 96.5% (GC/MS/MS) and 98.0% (GC/MS) with Method 1 higher than with Method 2. For woolong tea, 191 (GC/MS/MS) and 194 (GC/MS) pesticides and chemical pollutants accounted for 95% (GC/MS/MS) and 96% (GC/MS/MS) with Method 1, higher than with Method 2, respectively. In other words, there were definite differences in the test results for aged tea samples between Method 1 and Method 2, which suggests that Method 1 was capable of extracting more residual pesticides and chemical pollutants from the precipitated 165-day-aged tea samples. The reason can be traced to the possibility that Method 1 (high-speed homogenizing) has better extraction efficiency than Method 2 (vortex and oscillation). Therefore, Method 1 was chosen as the sample preparation technique for multiresidue pesticide and chemical pollutant analysis in tea.

scholarly journals Simultaneous Analysis of 70 Pesticides Using HPLC/MS/MS: A Comparison of the Multiresidue Method of Klein and Alder and the QuEChERS Method

2010 ◽  
Vol 93 (6) ◽  
pp. 1972-1986 ◽  
Author(s):  
Melanie Riedel ◽  
Karl Speer ◽  
Sven Stuke ◽  
Karl Schmeer
Keyword(s):  
Sample Preparation ◽  
Crude Extract ◽  
Extraction Efficiency ◽  
Ease Of Use ◽  
Simultaneous Analysis ◽  
Quechers Method ◽  
Multiresidue Method ◽  
Concentration Levels

Abstract Since 2003, two new multipesticide residue methods for screening crops for a large number of pesticides, developed by Klein and Alder and Anastassiades et al. (Quick, Easy, Cheap, Effective, Rugged, and Safe; QuEChERS), have been published. Our intention was to compare these two important methods on the basis of their extraction efficiency, reproducibility, ruggedness, ease of use, and speed. In total, 70 pesticides belonging to numerous different substance classes were analyzed at two concentration levels by applying both methods, using five different representative matrixes. In the case of the QuEChERS method, the results of the three sample preparation steps (crude extract, extract after SPE, and extract after SPE and acidification) were compared with each other and with the results obtained with the Klein and Alder method. The extraction efficiencies of the QuEChERS method were far higher, and the sample preparation was much quicker when the last two steps were omitted. In most cases, the extraction efficiencies after the first step were approximately 100. With extraction efficiencies of mostly less than 70, the Klein and Alder method did not compare favorably. Some analytes caused problems during evaluation, mostly due to matrix influences.

scholarly journals Rapid environmental analysis using molten salt fusion sample preparation

2011 ◽  
Vol 1 (1) ◽  
pp. 213-217
Author(s):  
C. E. Armenta ◽  
E. R. Gonzáles ◽  
J. A. Herrera ◽  
Alexander A. Plionis ◽  
D. S. Peterson
Keyword(s):  
Ion Exchange ◽  
Sample Preparation ◽  
Isotopic Composition ◽  
Molten Salt ◽  
Environmental Samples ◽  
Alpha Spectrometry ◽  
Chemical Exchange ◽  
Soil Samples ◽  
High Throughput Method ◽  
Subsequent Separation

Abstract For the analysis of the isotopic composition of environmental samples, including transuranic materials there are many methods that exist. This paper describes the development of a high throughput method, which involves dissolving a soil into an aqueous matrix, producing a homogenous mixture, and separating radionuclides to enable the identification of specific isotopes. A standard method was modified via changes in oxidation, chemical exchange, decomposition, or rearrangements to form constituents that are more soluble in acidic aqueous solutions. To accomplish this, a molten-salt fusion, dissolution in dilutes nitric or hydrochloric acids, with subsequent separation using ion exchange, direct deposition, and counting by alpha-spectrometry was used. This method is ideal for silicate samples, but can be modified to accommodate more complex soil samples.

scholarly journals Tantalum and Niobium Selective Extraction by Alkyl-Acetophenone

2018 ◽  
Author(s):  
Moussa Toure ◽  
Guilhem Arrachart ◽  
Jean Duhamet ◽  
Stephane Pellet-Rostaing
Keyword(s):  
Physicochemical Properties ◽  
Aqueous Phase ◽  
Organic Phase ◽  
Extraction Efficiency ◽  
Selective Extraction ◽  
Extraction Process ◽  
Liquid Extraction ◽  
Waste Solution ◽  
Liquid Liquid Extraction ◽  
Kd Values

A study has been carried out on Ta and Nb recovery by liquid-liquid extraction process using 4-methylacetophenone (4-MAcPh) as organic phase. The 4-MAcPh was compared to methylisobutylketone (MIBK) with respect to extraction efficiencies (kD values) at different concentrations of H2SO4 in the aqueous phase. The results showed a similar extraction of Nb for both solvents. However, for Ta extraction efficiency is increased by a factor of 1.3 for 4-MAcPh. In addition, the MIBK solubilized completely after 6 mol L-1 of H2SO4 against only a loss of 0.14 to 4% for 4-MAcPh between 6 and 9 mol L-1 of H2SO4. The potential of 4-MAcPh has also been studied to selectively recover Ta from a model capacitor waste solution. The results showed a selectivity for Ta in the presence of impurities such as Fe, Ni, Mn. The 4-MAcPh also presents the advantage of having physicochemical properties adapted to its use in liquid-liquid extraction technologies such as mixer-settlers.

scholarly journals Extraction of acyclovir from pharmaceutical creams for HPLC assay. Optimization and validation of pretreatment protocols

2008 ◽  
Vol 6 (2) ◽  
pp. 140-144 ◽  
Author(s):  
Paraskevas Tzanavaras ◽  
Constantinos Zacharis
Keyword(s):  
Extraction Efficiency ◽  
Monolithic Column ◽  
Extraction Yield ◽  
Extraction Kinetics ◽  
Time Intervals ◽  
Rapid Separation ◽  
Assay Optimization ◽  
Magnetic Stirring ◽  
Pharmaceutical Creams ◽  
Optimum Extraction

AbstractThree simple protocols for the extraction of acyclovir from its pharmaceutical creams based on ultrasonication, ultrasonication with heating and magnetic stirring were evaluated and compared. Extraction kinetics were studied at different time intervals (5, 10, 15, 30 and 60 min) and the extraction efficiency was determined by HPLC. The effect of concentration of aqueous NaOH as the extraction medium and the stirring speed were also studied and optimized. Best results were obtained with 50 mL of 0.01 mol L−1 aqueous NaOH with magnetic stirring speed of 500 r.p.m. HPLC analysis involved rapid separation of acyclovir from the cream matrix using a 100 × 4.6 mm i.d. monolithic column and UV detection at 254 nm. Magnetic stirring produced the best results in terms of extraction efficiency with an average extraction yield of 100.8%, n = 16 at an optimum extraction time of 15 min. The selected protocol was validated for within and day-to-day precision and ruggedness.

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