scholarly journals Salting-out extraction of catechol and hydroquinone from aqueous solutions and urine samples

2003 ◽  
Vol 2 (5) ◽  
pp. 293-299 ◽  
Author(s):  
Goran Nikolic ◽  
Jelica Perovic ◽  
Ruzica Nikolic ◽  
Milorad Cakic
Keyword(s):  
Aqueous Solutions ◽  
Extraction Efficiency ◽  
Model System ◽  
Diisopropyl Ether ◽  
Urine Samples ◽  
Optimal Conditions ◽  
Salting Out ◽  
Sodium Potassium ◽  
Real Samples ◽  
Magnesium Salts

The influence of ammonium, sodium, potassium, and magnesium chlorides and sulfates on the extraction of catechol and hydroquinone with diethyl and diisopropyl ether was studied. All the salts investigated in this study largely increased the extraction efficiency of both catechol and hydroquinone from aqueous solutions, magnesium salts being the most efficient salting-out agents. The extraction efficiency in the presence of magnesium salts in comparison to the extraction efficiencies from the salt-free aqueous solutions increased from 14%, in the case of catechol extraction with diethyl ether, up to about 90%, in the case of hydroquinone extraction with diisopropyl ether. The extraction from spiked urine samples proved that investigation of salting-out effect in aqueous solutions could be used as a good model system for the reliable choice of optimal conditions for catechol and hydroquinone extraction from real samples.

scholarly journals Enhanced Adsorption of Bisphenol A from Aqueous Solution with 2-Vinylpyridine Functionalized Magnetic Nanoparticles

Polymers ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1136 ◽  
Author(s):  
Qiang Li ◽  
Fei Pan ◽  
Wentao Li ◽  
Dongya Li ◽  
Haiming Xu ◽  
...  
Keyword(s):  
Bisphenol A ◽  
Aqueous Solutions ◽  
Adsorption Capacity ◽  
Magnetic Nanoparticle ◽  
Maximum Adsorption Capacity ◽  
Salting Out ◽  
Functionalized Magnetic Nanoparticles ◽  
Ft Ir ◽  
Fe3o4 Nanospheres ◽  
Enhanced Adsorption

In this study, a novel 2-vinylpyridine functionalized magnetic nanoparticle (Mag-PVP) was successfully prepared. The prepared Mag-PVP was characterized by transmission electronic microscopy (TEM), Fourier transform infrared spectrophotometry (FT-IR), vibrating sample magnetometry (VSM) and thermogravimetric analysis (TGA), and was used for the adsorption of bisphenol A (BPA) from aqueous solutions. Mag-PVP, which is composed of Fe3O4 nanoparticles and poly divinylbenzene-2-vinylpyridine (with a thickness of 10 nm), exhibited magnetic properties (Ms = 44.6 emu/g) and thermal stability. The maximum adsorption capacity (Qm) of Mag-PVP for BPA obtained from the Langmuir isotherm was 115.87 mg/g at 20 °C, which was more than that of Fe3O4 nanospheres. In the presence of NaCl, the improved adsorption capacity of Mag-PVP was probably attributed to the screening effect of Mag-PVP surface charge and salting-out effect. In the presence of CaCl2 and humic acid (HA), the adsorption capacity of BPA decreased due to competitive adsorption. The adsorption of BPA by Mag-PVP increased slightly with the increase in pH from 3.0 to 5.0 and obtained the largest adsorption amount at pH 5.0, which was probably attributed to hydrogen bonding interactions. Moreover, in actual water, Mag-PVP still showed excellent adsorption performance in removing BPA. The high adsorption capacity and excellent reusability performance in this work indicated that Mag-PVP was an effective adsorbent for removing BPA from aqueous solutions.

scholarly journals Analytical and physiological validation of an enzyme immunoassay to measure oxytocin in dog, wolf, and human urine samples

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
G. Wirobski ◽  
F. S. Schaebs ◽  
F. Range ◽  
S. Marshall-Pescini ◽  
T. Deschner
Keyword(s):  
Enzyme Immunoassay ◽  
Human Urine ◽  
Extraction Efficiency ◽  
Urine Samples ◽  
Antibody Specificity ◽  
Analytical Validation ◽  
Human Urine Samples ◽  
Assay Performance ◽  
Fit For Purpose ◽  
Commercial Enzyme Immunoassay

AbstractOxytocin (OT) promotes pro-sociality, bonding, and cooperation in a variety of species. Measuring oxytocin metabolite (OTM) concentrations in urine or saliva provides intriguing opportunities to study human and animal behaviour with minimal disturbance. However, a thorough validation of analytical methods and an assessment of the physiological significance of these measures are essential. We conducted an analytical validation of a commercial Enzyme Immunoassay (EIA; Arbor OT assay kit) to measure OTM concentrations in dog, wolf, and human urine samples. To test the assay’s ability to detect changes in OTM concentrations, we administered oxytocin intranasally to 14 dogs. Assay performance with regard to parallelism was acceptable. Assay accuracy and extraction efficiency for dog and wolf samples were comparable to a previously validated assay (Enzo OT assay kit) but variation was smaller for human samples. Binding sensitivity and antibody specificity were better in the Arbor assay. Average OTM concentrations were more than twice as high as in comparable samples measured with the Enzo assay, highlighting a lack of comparability of absolute values between different assays. Changes in OTM concentrations after intranasal treatment were detected reliably. The Arbor assay met requirements of a “fit-for-purpose” validation with improvement of several parameters compared to the Enzo assay.

scholarly journals A Novel Green Extraction Technique for Extracting Flavonoids from Folium nelumbinis by Changing Osmosis Pressure

Materials ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4192
Author(s):  
Hai-Yan Fang ◽  
Ying-Qin Wei ◽  
Meng-Li Zhang ◽  
Wei Liu
Keyword(s):  
Extraction Efficiency ◽  
Chemical Potential ◽  
Volume Fraction ◽  
Antioxidant Activities ◽  
Morphological Changes ◽  
Extraction Process ◽  
Extraction Technique ◽  
Salting Out ◽  
Digital Microscope ◽  
Main Factor

A new green and sustainable extraction technique, namely osmosis extraction (OE), was developed for efficient extracting flavonoids from Folium nelumbinis by changing the osmotic pressure. The antioxidant activities of the extracted flavonoids were also evaluated. Ethanol and ammonium sulfate were selected for the OE system because they are environmentally friendly. The maximum flavonoids concentration in the top phase was obtained with an ethanol volume fraction of 42.0% and the salt mass of 1.9 g. The kinetic behavior of the extraction process showed that OE had higher efficiencies especially coupled with ultrasonication due to the accompanying and serious morphological changes of Folium nelumbinis cells observed by digital microscope and nano-computed tomography (nano-CT). Results of morphological and anatomical features showed that the higher intracellular chemical potential made the cell expand and even led to bursting. The results also showed that the extraction efficiency of flavonoids with high antioxidant activities was higher than that of the traditional method. The interface effect enhanced the extraction during the salting-out extraction and osmosis was the main factor that improved the extraction efficiency.

Salting-out assisted liquid-liquid extraction method combined with GC-MS for the determination of topiramate in aqueous solutions: development and application of the methodology

2019 ◽  
Vol 55 (13) ◽  
pp. 2303-2312 ◽  
Author(s):  
Janiele Mayara Ferreira De Almeida ◽  
Elania Maria Fernandes Silva ◽  
Lourena Mafra Veríssimo ◽  
Nedja Suely Fernandes
Keyword(s):  
Aqueous Solutions ◽  
Extraction Method ◽  
Liquid Extraction ◽  
Salting Out ◽  
Liquid Liquid Extraction

scholarly journals Resistance of Listeria monocytogenes biofilms to disinfectants 326

2010 ◽  
Vol 28 (No. 4) ◽  
pp. 326-332 ◽  
Author(s):  
S. Purkrtová ◽  
H. Turoňová ◽  
T. Pilchová ◽  
K. Demnerová ◽  
J. Pazlarová
Keyword(s):  
Listeria Monocytogenes ◽  
Reference Strain ◽  
Model Organism ◽  
Model System ◽  
Optimal Conditions ◽  
Microtiter Plates ◽  
Peptone Water ◽  
Optimal Values ◽  
Biofilm Development ◽  
Chloride Treatment

We studied the optimal conditions for the biofilm development by Listeria monocytogenes on a model system represented by microtiter plates, and also for determined some effective disinfectant agents. Listeria monocytogenes ATCC 13932 and an industrial isolate of Listeria monocytogenes Lm-24 were compared as to their abilities to form biofilms. The starting concentration of the cells leading to the most reproducible results was 0.5 McFarland. The temperatures tested ranged between 8°C to 37°C, the optimal values to form biofilm in buffered peptone water (BPW) with 0.05% glucose were 25°C and 30°C. Under comparable conditions the persistent strain L. monocytogenes Lm-24 constituted more massive biofilm than did the reference strain. The following disinfectants were applied: Savo, Merades Alco, benzalalkonium chloride. A persistent industry in isolate Listeria monocytogenes Lm-24 was used as the model organism for these tests. Benzalalkonium chloride treatment was found to be the most efficient way to damage the biofilm. One minute treatment with 500 mg/l was lethal for the biofilm cells, and that with 125 mg/l for planctonic cells. Savo suppresed the viability of the biofilm cells only by about 20% on average while being lethal for planctonic cells. Merades Alco exhibited only a weak effect on both the biofilm and planctonic cells.

scholarly journals Recovery of gangliosides from aqueous solutions on styrene-divinylbenzene copolymer columns

2002 ◽  
Vol 43 (8) ◽  
pp. 1335-1340 ◽  
Author(s):  
Iuliana Popa ◽  
Cristina Vlad ◽  
Jacques Bodennec ◽  
Jacques Portoukalian
Keyword(s):  
Aqueous Solutions ◽  
Silica Gel ◽  
Salt Concentration ◽  
High Stability ◽  
Solid Phase ◽  
General Procedure ◽  
Optimal Conditions ◽  
Alkaline Conditions ◽  
Styrene Divinylbenzene ◽  
Multiple Cycles

An investigation was made using a styrene-divinylbenzene copolymer as a solid phase sorbent to recover gangliosides from aqueous solutions. A comparison with octadecyl-bonded (C18) silica gel showed that the general procedure used to purify gangliosides on C18 silica gel could be used with the copolymer. The yield of gangliosides depended on various parameters such as the composition of the conditioning solution, the salt concentration of the loading solution, and the amount of applied gangliosides per gram of copolymer. In optimal conditions, the recovery of gangliosides and other lipids present in the upper phases of partition was higher than 95%. Using radiolabeled gangliosides, it was found that gangliosides present in serum-containing medium could also be quantitatively recovered on copolymer, provided the medium was diluted with an equal volume of methanol prior to its application onto the column.The major advantage of the copolymer is its high stability in acidic or alkaline conditions that allows multiple cycles of cleaning and reconditioning of the sorbent without alteration of its chromatographic properties.

An automated salting-out assisted liquid-liquid microextraction approach using 1-octylamine: On-line separation of tetracycline in urine samples followed by HPLC-UV determination

Talanta ◽  
2018 ◽  
Vol 184 ◽  
pp. 122-127 ◽  
Author(s):  
Ksenia Cherkashina ◽  
Christina Vakh ◽  
Sofya Lebedinets ◽  
Aleksei Pochivalov ◽  
Leonid Moskvin ◽  
...  
Keyword(s):  
Urine Samples ◽  
Salting Out ◽  
On Line ◽  
Line Separation ◽  
Liquid Microextraction
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