Organic Extraction Phase Research Articles

Plasma antioxidants and risk of dementia in older adults.

IntroductionPlant‐based diets rich in fruits and vegetables have been associated with lower risk of dementia, but the specific role of antioxidants, a key class of bioactive phytochemicals, has not been well ascertained.MethodsWe measured antioxidants in a case‐cohort study nested within the Ginkgo Evaluation of Memory Study. We included 996 randomly selected participants and 521 participants who developed dementia, of which 351 were diagnosed with Alzheimer's disease (AD) during a median of 5.9 years of follow‐up. We measured baseline plasma levels of retinol, α‐, and γ‐tocopherol; zeaxanthin and lutein (combined); beta‐cryptoxanthin; cis‐lycopene; trans‐lycopene; α‐carotene; and trans‐β‐carotene by organic phase extraction followed by chromatographic analysis and related these to neurologist‐adjudicated risks of all‐cause dementia and AD.ResultsPlasma retinol, α‐, and γ‐tocopherol, and carotenoids were not significantly related to risk of dementia or AD. Associations were not significant upon Bonferroni correction for multiple testing and were consistent within strata of sex, age, apolipoprotein E ε4 genotype, mild cognitive impairment at baseline, and intake of multivitamin, vitamin A or β‐carotene, or vitamin E supplements. Higher trans‐β‐carotene tended to be related to a higher risk of dementia (adjusted hazard ratio [HR] per 1 standard deviation [SD] higher trans‐β‐carotene: 1.10; 95% confidence interval [CI]: 1.00, 1.20) and α‐carotene tended to be associated with higher risk of AD only (adjusted HR per 1 SD higher α‐carotene: 1.15; 95% CI: 1.02, 1.29).DiscussionPlasma antioxidants were not significantly associated with risk of dementia or AD among older adults. Similar studies in younger populations are required to better understand the association between plasma antioxidants and dementia risk.

Experimental Modeling of Technetium(VII) Recovery from Raffinates after Extractive Reprocessing of Spent Nuclear Fuel

Experimental justification has been provided for the possibility of extractive isolation of technetium from raffinate of technical process of affinage of uranium–plutonium product resulting from hydrometallurgical reprocessing of spent nuclear fuel (SNF). Technetium (VII) from aqueous solution of Zr(IV) (10 g/L) and 4 mol/L HNO3 with small content of ZrOb+ and $${\text{Z}}{{{\text{r}}}_{{\text{2}}}}{\text{O}}_{{\text{3}}}^{{b + }}$$ oxocations is recovered by 80% in 30% TBP in hydrocarbon diluent over seven stages of counter-current continuous cascade at ratio O : A = 1 : 1. Variation in phase flow ratio for cascade part leads to virtually complete Tc(VII) extraction in organic phase over ten stages. Technetium(VII) is selectively back extracted from loaded organic phase with water virtually completely over eleven stages of counter-current continuous cascade. Technological extraction scheme for technetium isolation from SNF solutions has been proposed.

Facile fractionation of bamboo hydrolysate and characterization of isolated lignin and lignin-carbohydrate complexes

Abstract An efficient separation technology for hydrolysates towards a full valorization of bamboo is still a tough challenge, especially regarding the lignin and lignin-carbohydrate complexes (LCCs). The present study aimed to develop a facile approach using organic solvent extraction for efficiently fractionating the main components of bamboo hydrolysates. The high-purity lignin with only a trace of carbohydrates was first obtained by precipitation of the bamboo hydrolysate. The water-soluble lignin (WSL) fraction was extracted in organic solvent through a three-stage organic solvent extraction process, and the hemicellulosic sugars with increased purity were also collected. Furthermore, a thorough characterization including various NMR techniques (31P, 13C, and 2D-HSQC), GPC, and GC-MS was conducted to the obtained lignin-rich-fractions. It was found that the WSL fraction contained abundant functional groups and tremendous amount of LCC structures. As compared to native LCC of bamboo, the WSL fraction exhibited more typical LCC linkages, i.e. phenyl glycoside linkage, which is the main type of chemical linkage between lignin and carbohydrate in both LCC samples. The results demonstrate that organic phase extraction is a highly efficient protocol for the fractionation of hydrolysate and the isolation of LCC-rich streams possessing great potential applications.

Preparation of single O-methoxyphenol from lignin and related liquor products as reinforcement for epoxy resin

The mass application of lignin is challenging due to poor processability and low reactivity. The processes to refine lignin into fine chemicals always tedious and produce multi-components chemicals, which cannot be utilized directly. In this work, hot-compressed ethanol/H 2 O has been adopted to treat lignin to realize its atomic economy utilization. The single O-methoxyphenol chemical has been obtained by convenient organic phase extraction, and the partial depolymerization products contain in aqueous phase. The partial depolymerization products have been applied for preparation of epoxy resin composite. The mechanical properties of the epoxy resin/lignin composites are considerably improved due to the chemical interaction between the activated depolymerized lignin and epoxy. Additionally, an amino-functionalized depolymerization was inspected by introducing amine into the ethanol/H 2 O medium, by which the curing agent usage can be partially reduced. This study provides an efficient strategy for lignin utilization to obtain O-methoxyphenol and high-performance polymer composite. • A hot-compressed ethanol/H 2 O has been adopted for activation of lignin. • The single O-methoxyphenol chemical has been extracted from reaction liquor. • The tensile strength of the as-prepared composite has been improved by about 62%.

Optimization of genomic DNA extraction protocol for black wattle

Considerando-se que a atual tendência do melhoramento florestal é a integração das técnicas clássicas com as de análise genética molecular, faz-se necessária a obtenção de protocolos de extração de DNA genômico ajustados a cada espécie estudada. O objetivo do trabalho foi determinar o efeito de diferentes adaptações no protocolo de extração de DNA genômico CTAB para acácia-negra. Foram testados diferentes componentes na fase de extração orgânica: clorofórmio, fenol e proteinase K, além da aplicação de RNase após a fase de precipitação e limpeza do DNA. Também, foi investigada a eficiência destes tratamentos em amostras de folíolos frescas ou armazenadas em baixa temperatura durante sete dias. Foi verificada a presença de DNA de todas as amostras submetidas à extração pelo protocolo de CTAB com os diferentes tratamentos. O tempo de armazenamento das amostras não influenciou na integridade do DNA, entretanto, foi possível observar que a adição de RNase melhorou a qualidade do DNA extraído. Deste modo, sugere-se a utilização do protocolo CTAB com uso de clorofórmio e RNase, com amostras frescas ou armazenadas em baixas temperaturas.

Simultaneous determination of free and total paclitaxel in blood in a three-phase laminar flow microchip

In this study, a three-phase laminar flow microfluidic chip (TPL chip) combined with HPLC was developed for monitoring free and total concentrations of paclitaxel (PTX) in blood simultaneously. A diluted whole blood sample (aqueous phase) was introduced into the chip, ethyl acetate (organic phase) was introduced into the chip for extraction, and an interphase was used to prevent the blood sample from coming into direct contact with the organic phase. Because only free drug can quantitatively diffuse into the organic extraction phase and the free drug fraction has a linear relationship with the dilution factor of blood, both the free and total drug concentrations can be obtained by detecting the concentration of paclitaxel in the organic extraction phase. The governing factor such as flow rate for extraction was optimized. Docetaxel was used as an internal standard. The reliability of the quantitative diffusion of molecules in the TPL chip was proved by the methodological investigation of PTX in PBS sample, which showed a good linearity in the concentration range of 0.5 - 100µg/mL and a detection limit of 7ng/mL. Good repeatibilities for retention time (RSD of PTX is 1.23%, docetaxel is 1.14%, n=5) and peak area ratio of PTX to docetaxel (RSD is 4.38%) were obtained. For blood sample analysis, only 100 µL of sample was needed and whole pretreatment was finished in 35min, and a recovery of 94~117% were obtained. The provided method showed advantages in fast analysis speed, minimum sample handing, and potential ability of automation, and integration.

Adsorption and corrosion inhibition performance of multi-phytoconstituents from Dioscorea septemloba on carbon steel in acidic media: Characterization, experimental and theoretical studies

The adsorption and corrosion inhibition performance of the water phase and organic phase extracts from Dioscorea septemloba on carbon steel have been carried out in 1 M HCl solutions. Extracts characterization was accomplished by NMR spectroscopy and the generic carbohydrate test. Electrochemical techniques and gravimetry were utilized for the evaluation of corrosion inhibition behaviors. 3D surface measurement instrument, SEM, and FT-IR were used to examine the surface properties of carbon steel coupons after full immersion in 1 M HCl solutions without and with the extracts. Quantum chemical calculation (QCC) and molecular dynamics simulation (MDS) were used to predict and describe the electronic and adsorption properties of some characterized compounds in the extracts. Both extracts exhibited similar corrosion inhibition behaviors acting as mixed-type inhibitors and having their efficiencies dependent on concentration and temperature. Time-dependent corrosion evaluation showed that the inhibition efficiencies of the extracts were improved with time. Low surface roughness data were recorded for the extracts by 3D surface measurements and the results were consistent with the observations from SEM micrographs and FT-IR spectra. Computational parameters obtained from QCC and MDS were used to predict the adsorption behavior of some characterized compounds from the extracts.

Decomposition of deep eutectic solvents based on choline chloride and phenol in aqueous phase

Deep eutectic solvents (DESs) are compounds formed by donor and acceptor of hydrogen bond in a liquid state at ambient temperature. They are non-volatile, with high thermal stability and readily dissolve many organic and inorganic compounds. DESs based on choline chloride and phenol have recently appeared in analytical practice and have already found wide application in various fields. The numerous articles have been reported efficient liquid-liquid extraction using these DESs as extraction solvents. In this paper the process of liquid-liquid extraction using DESs based on choline chloride and phenol was investigated. It was established that the DES decomposition in aqueous phase takes place due to the dissociation of choline and phenol, which leads to the destruction of the hydrogen bond. In addition, with the addition of an aprotic solvent, tetrahydrofuran, the extraction of organic phase is observed. This phase was mistakenly used as DES, but in our study we showed that this phase consists of tetrahydrofuran, water and phenol, which is not the initial phase of DES. This phenomenon was investigated by gas chromatography with mass spectrometric detection and coulometric Karl-Fischer titration It was confirmed that these DESs cannot be considered as extraction solvents in liquid-liquid extraction from aqueous solutions. The main goal of the present work is to pay attention of researchers to a wrong conception in liquid-liquid extraction using DESs based on choline chloride and phenol to avoid mistakes in the future.

Biobased Support Layers for the Fractionation and Selective Extraction of Lignosulfonates

ABSTRACTThe paper presents an experimental study on the preparation and characterization of cellulose films and their use for reactive lignosulfonate extraction. The extraction of lignosulfonates leads to emulsion and crud formation when standard equipment is applied. By using cellulose films as a support layer between the aqueous feed phase and the organic extractant phase, emulsion formation is prevented. The results showed that selective separation and a fractionation of the lignosulfonates can be realized with this novel approach simultaneously.

Study of the products of radiation and thermal destruction in the extraction system of 30 vol% TBP–Isopar-M–HNO3

The composition of the products of radiation and radiation-thermal destruction of the PUREX extraction organic phase of 30 vol% TBP in the Isopar-M diluent, pre-saturated with nitric acid, was studied. The composition of the formed functional derivatives was determined as an effect of the concentration of nitric acid, radiation dose and heating temperature. Methods of FTIR and NMR spectroscopies and gas chromatography were applied to analyze the decay products. It was revealed that the nitro-compounds and carboxylic acids dominate among other radiolysis products. The concentration of carboxylic acids in the heated samples sharply increases with the dose of preliminary irradiation.

Separation of f-elements by resins impregnated with amides of pyridine-2,6-dicarboxylic acid

Chemistries of trivalent lanthanides and actinides under aqueous processing conditions are so similar that their satisfying separation is extremely challenging. Preparation of a functionalized solid material by impregnation of a support resin with an organic extraction phase is one of possible routes for novel materials development. The ortho- and para-dialkyl-diaryl-pyridine-2,6-dicarboxyamides were impregnated into two macroporous matrices (PS-DVB and PMA). Influence of the diamide structure, matrix type and conditions for effective extraction chromatography separation of Am(III) from Eu(III) was studied in dynamic conditions. The prepared sorbents exhibited more strong adsorptions of Am(III) to compare with Eu(III). Maximal separation factor (~ 90) was achieved with use of citrate ion as complexing eluent.

Effects of Copper Solvent Extraction Reagents on metabolism and Leaching Efficiency of Bioleaching Bacteria

In the process of copper biohydrometallurgy, a small amount of copper extractant organic phase will remain in raffinate by entrainment of dissolving and emulsion droplets. Copper extraction organic phase can poison the bacteria and further affect the bioleaching process.The effects of organic extractants containing ketoximes and oximes on the metabolism of Acidithiobacillus ferrooxidans (A.ferrooxidans) and its bioleaching efficiency were studied. The results showed that the presence of organic phase inhibited bacterial metabolism and reduced its leaching activity.

Determination of nicotine in saliva, urine and wastewater samples using tantalum metal organic framework pipette tip micro-solid phase extraction

A novel tantalum metal organic framework (Ta-MOF) was synthesized by a microwave assisted reverse micelle procedure, and it was used as a sorbent for pipette tip micro-solid phase extraction of nicotine from biological and environmental samples.

DNA Extraction from Various Types of Prenatal Specimens.

A prenatal noninvasive genetic screening test that yields a positive result typically warrants further direct assessment of fetal DNA following an invasive procedure. The precious nature of these invasively acquired samples, combined with the time sensitive nature with which results should be reported, demands that the methodologies used for analysis be quick, efficient, and dependable.Prenatal diagnosis has been performed using DNA extracted from amniotic fluid and chorionic villi for several decades, and more recently methodologies have been developed to extract cell free fetal DNA from amniotic fluid. DNA extraction methodologies in these matrices should reliably and reproducibly isolate a sufficient quality and quantity of DNA for the intended downstream application, and make it possible to purify and concentrate samples that may arrive with suboptimal quality or quantity.Phenol-Chloroform extraction followed by DNA precipitation in ethanol has historically been used for prenatal samples, but this methodology is labor intensive, time consuming, and requires use of toxic chemicals. There are now commercially available, solid phase-based kits for rapid and reproducible DNA extraction and purification, enabling simultaneous extraction of a large number of samples. Commercial kits are available for a variety of sample matrices including all prenatal specimen types, although other methodologies including organic or inorganic liquid phase extraction may also be utilized.Here, we describe extraction using both commercially available kits for direct amniocytes and chorionic villi and cell free fetal DNA derived from amniotic fluid, as well as inorganic liquid phase extraction for tissue culture of amniocytes, CVS, and products of conception.

Renewable Energy from Agricultural Waste

This paper has aimed at evaluating the concentration of bioethanol obtained using sunflower stem as natural support, molasses as carbon source and Saccharomyces cerevisiae yeast in a continuous flow reactor. The natural support was tested to investigate the immobilization/growth of S. cerevisiae yeast. The concentration of bioethanol produced by fermentation was analyzed by gas chromatography using two methods: aqueous solutions and extraction in organic phase. The CO2 flow obtained during the fermentation process was considered to estimate when the yeast was deactivated. The laboratory experiments have highlighted that the use of plant-based wastes to bioconversion in ethanol could be a non-pollutant and sustainable alternative.

Melamine-based porous organic polymers inline solid phase extraction coupled with high performance liquid chromatography for the analysis of phytohormones in juice samples

A melamine-based porous organic polymer (mPMF) was synthesized as solid phase extraction (SPE) adsorbent for inline SPE-high performance liquid chromatography (HPLC)-ultraviolet detector (UV) analysis of five phytohormones. Melamine contributed to the rich π-electron and N-containing triazine structure for mPMF, which could form π-π interaction and intermolecular hydrogen bond with COOH containing phytohormones. The synthesized mPMF adsorbent shows extremely high extraction efficiency for five target analytes (>80%) including salicylic acid, indole-3-acetic acid, abscisic acid, 2,4-dichlorophenoxyacetic acid and 1-naphthalene acetic acid. The factors affecting extraction of the target phytohormones were investigated and the optimized experimental conditions were established. The linear range was 0.2–100 μg/L with the limits of detection in the range of 0.06–0.11 μg/L for five target phytohormones. The developed method of mPMF-inline-SPE-HPLC-UV was applied for the analysis of trace target phytohormones in tomato and grape juice samples, and the recovery in the range of 83.1–116% and 87.2–121% was obtained for the spiked tomato and grape juice, respectively. This method has the advantages of high sensitivity and good reproducibility, and it has good application potential for the analysis of phytohormones in fruit samples. Moreover, inline analysis avoided the problems of sample pollution and sample loss, and provided a sample throughput of 5/h.

Application of a surfactant-assisted dispersive liquid-liquid microextraction method along with central composite design for micro-volume based spectrophotometric determination of low level of Cr(VI) ions in aquatic samples

A fast, simple, low cost surfactant-assisted dispersive liquid-liquid microextraction method along with central composite design for the determination of low level of Cr(VI) ions in several aquatic samples has been developed. Initially, Cr(VI) ions present in the aqueous sample were readily reacted with 1,5‑diphenylcarbazide (DPC) in acidic medium through complexation. Sodium dodecyl sulfate (SDS), as an anionic surfactant, was then employed as an ion-pair agent to convert the cationic complex into the neutral one. Following on, the whole aqueous phase underwent a dispersive liquid-liquid microextraction (DLLME) leading to the transfer of the neutral complex into the fine droplet of organic extraction phase. A micro-volume spectrophotometer was used to determine Cr(VI) concentrations. Under the optimized conditions predicted by the statistical design, the limit of quantification (LOQ) obtained was reported to be 5.0 μg/L, and the calibration curve was linear over the concentration range of 5–100 μg/L. Finally, the method was successfully implemented for the determination of low levels of Cr(VI) ions in various real aquatic samples and the accuracies fell within the range of 83–102%, while the precision varied in the span of 1.7–5.2%.

BPA exposure is associated with non-monotonic alteration in ESR1 promoter methylation in peripheral blood of men and shorter relative telomere length in peripheral blood of women.

The aim of this study was to evaluate the potential association of urinary Bisphenol A (BPA) levels with estrogen receptor alpha (ESR1) promoter % methylation and relative telomere length in a sample of 482 participants. Urinary BPA concentration was measured using organic phase extraction followed by high performance liquid chromatography mass spectroscopy. Peripheral blood ESR1 promoter % methylation and relative telomere length were measured using direct bisulfite sequencing and real-time polymerase chain reaction, respectively. The mean ± SD urinary BPA concentration adjusted for urinary creatinine was 2.90 ± 4.81 (μg/g creatinine) with a median of 1.86 μg/g creatinine (min-max: <LOD -69.85). There was a potentially non-monotonic relationship between adjusted urinary BPA concentrations and ESR1 promoter % methylation in men. As a matter of fact, for the lowest tertile of ESR1 promoter % methylation, the OR and 95% CI of the middle and highest tertiles of urinary adjusted BPA were 2.54 (1.01-6.39) and 1.64 (0.55-4.86) when compared to the lowest BPA tertile, respectively. After adjustment for potential confounders, similar results remained in men and appeared in the whole cohort. As for relative telomere length, there was a significant trend whereby higher adjusted urinary BPA concentrations were significantly associated with shorter relative telomere length in females. For instance, for the shortest relative telomere length tertile, the OR and 95% CI of the middle and highest tertiles of urinary adjusted BPA were 2.91 (1.38-6.16) and 3.19 (1.57-6.49) when compared to the lowest BPA tertile, respectively. This trend remained significant after adjustment for potential confounders.

Solvent-stir bar microextraction system using pure tris-(2-ethylhexyl) phosphate as supported liquid membrane: A new and efficient design for the extraction of malondialdehyde from biological fluids

A novel and efficient device of solvent stir-bar microextraction (SSBME) system coupled with GC-FID detection was introduced for the pre-concentration and determination of malondialdehyde (MDA) in different biological matrices. In the proposed device, a piece of porous hollow fiber was located on a magnetic rotor by using a stainless steel-wire (as a mechanical support) and the whole device could stir with the magnetic rotor in sample solution cell. The device provided higher pre-concentration factor and better precision in comparison with conventional SBME due to the reproducible, stable and high contact area between the stirred sample and the hollow fiber. Organic solvent type, donor and acceptor phase pH, temperature, electrolyte concentration, agitation speed, extraction time, and sample volume as the effective factors on the SSBME efficiency, were examined and optimized. Pure tris-(2-ethylhexyl) phosphate (TEHP) was examined for the first time as supported liquid membrane (SLM) for the determination of MDA by SSBME method. In contrast to the conventional SLMs of SBME in the literature, the SLM of TEHP was highly stable in contact with biological fluids and provided the highest extraction efficiency. Under optimized extraction conditions, the method provided satisfactory linearity in the range 1–500 ng mL−1, low LODs (0.3–0.7 ng mL−1), good repeatability and reproducibility (RSD% (n = 5) < 4.5) with the pre-concentration factors higher than 130-fold. To verify the accuracy of the proposed method, the traditional spectrophotometric TBA (2-thiobarbituric acid) test was used as a reference method. Finally, the proposed method was successfully applied for the determination and quantification of MDA in biological fluids.

Solvent Extraction of Rare Earth Elements from a Nitric Acid Leach Solution of Apatite by Mixtures of Tributyl Phosphate and Di-(2-ethylhexyl) Phosphoric Acid

Solvent extraction of rare earths from nitrate leach liquor of apatite using mixtures of tributyl phosphate (TBP) and di-(2-ethylhexyl) phosphoric acid (D2EHPA) was studied. The effects of nitrate and hydrogen ion concentration of the aqueous phase as well as the composition and concentration of extractants in the organic phase on the extraction behavior of lanthanum, cerium, neodymium, and yttrium were investigated. The distribution ratio of REEs increases by increasing the nitrate concentration in aqueous phase and concentration of extractants in organic phase, but the hydrogen ion concentration in aqueous phase has a decreasing effect. Yttrium as a heavy rare earth is more sensitive to these parameters than light rare earth elements. Although the composition of organic phase has a minor effect on the extraction of light rare earths, the percent of extraction of yttrium decreases dramatically by increasing the TBP content of organic phase. Mixtures of TBP and D2EHPA can show either synergism or antagonism extraction depending on the concentration and composition of extractants in organic phase. The best condition for separating rare earth elements in groups of heavy and light REEs can be achieved at high nitrate concentration, low H+ concentration, and high concentration of D2EHPA in organic phase. Separation of Ce and La by TBP and D2EHPA is practically impossible in the studied conditions; however, low nitrate concentration and high hydrogen ion concentration in aqueous phase and low concentration of extractants in organic phase favor the separation of Nd from other light rare earth elements.