Phase Extraction Liquid Research Articles

Deposition of hydrogen chloride gas on copper wafer depending on humidity and HCl concentration

Residual volatile HCl acid remaining on the wafer surface after certain microelectronic fabrication can lead to the yield defectiveness of integrated circuits made of copper (Cu). The control of HCl contamination is a key point to avoid the yield loss. In order to elucidate the deposition mechanism of HCl on copper surface, Cu-coated wafers were exposed to HCl at different HCl airborne concentrations (20–450 ppbv) and at different relative humidity (<1%–70% RH). Liquid phase extraction (LPE) and ionic chromatography (IC) allow to quantitatively determine the amount of deposited chloride at given time, humidity and HCl airborne concentration. Below a threshold of 1.25 × 1015 Cl atom.cm−2, a linear behavior of HCl deposition on Cu-coated wafer is observed depending on airborne concentration and time regardless of the humidity (dry <1% RH up to humid 70% RH). In particular, at high humidity (70% RH), a plateau of 1.5 × 1015 Cl atom.cm−2 on Cu surface is steadily maintained whatever the increase of either exposure time or HCl airborne contamination. Besides, the key role of humidity (RH%) in the formation of various Cu compounds and the oxidation states of Cu at given exposure conditions are also elucidated by XPS measurements. An empirical-mathematical model of deposition HCl on Cu was established, which could be served as an industrial tool to predict the contamination transfer to wafer during storage in FOUPs.

An Automatic Solid Phase Extraction and Ultra-Performance Liquid Chromatography Tandem Mass Spectrometry for Determination of Seven Microcystins at Ultra-Trace Levels in Surface Water

A method was developed for the detection of seven microcystins (microcystin-LR, RR, YR, LA, LY, LW and LF) in surface water using automatic solid-phase extraction (A-SPE) coupled with ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The automated solid-phase extraction system was used to extract microcystins (MCs) from water samples. UPLC-MS/MS was used to determine MCs concentrations in just 5 min. Method detection limits were from 0.3 to 0.9 ng/L, microcystin recoveries ranged from 83.8% to 114%, and the relative standard deviation (RSD) varied from 5.6% to 12.5%. This analytical approach was found to be simple, highly sensitive, accurate, which required little manual operation. Additionally, to validate this analytical method, A-SPE+UPLC-MS/MS was applied to characterize the concentration of MCs in Taihu Lake, Wuxi, China.

Determination of 18 phenolic acids in tobacco and rhizosphere soil by ultra high performance liquid chromatography combined with triple quadrupole mass spectrometry.

An ultra high performance liquid chromatography with triple quadrupole mass spectrometry method for the determination of free and bound phenolic acids in tobacco plant and soil was developed. A simple solid-phase extraction, which used Polar Enhanced Polymer column as stationary phase and methanol as mobile phase, was used for the clean-up of bound phenolic acids, and a liquid-phase extraction using chloroform as solvent was used to purify free phenolic acids. With our method, 18 phenolic acids in rhizosphere soil of continuous cropping flue-cured cultivar k326 were separated and determined within 6min with recoveries of 82-107% and relative standard deviations (n=5) of 1.1-4.8%. Results showed that free phenolic acids accounted for 0-9, 92-100, and 69-100% of total phenolic acids in rhizosphere soil, cultivar k326 roots and leaves, respectively. Results also revealed that p-hydroxybenzoic acid, p-coumaric acid, vanillic acid, ferulic acid, and syringic acid were the predominant phenolic acids in rhizosphere soil of cultivar k326, and continuous cropping of cultivar k326 in the same farmland could lead to the accumulation of these phenolic acids in soil except syringic acid. The determination of phenolic acids provided detailed information for evaluating their source and characteristics in continuous cropping tobacco plant and soil.

Preliminary studies on the occurrence of nonylphenol in the marine environments, Chennai\u2014a case study

BackgroundResisting degradation, nonylphenol (NP) remains as a critical compound contaminating many habitats. Prevalence of nonylphenol in the ecosystem of Indian coastlines is not well documented as that of fresh water. Hence, the present study was intended to estimate the concentration of nonylphenol from water and sediments samples of Chennai (Madras) coastline which is polluted with anthropogenic activities from the city.ResultsSix stations were sampled such as Ennore mouth, Ennore creek, Kasimedu, Marina, Besant Nagar, and Muttukaadu which covered approx. 50 km of south-east coastline. Nonylphenol was extracted from water and sediment samples by liquid and solid phase extraction respectively and quantified using gas chromatogram coupled mass spectrum (GC-MS). All the sites were contaminated with nonylphenol (NP) of which at Ennore mouth, concentrations were above the United States Environmental Protection Agency (US EPA) prescribed environmental safety limit of 1.7 μg/l. Nonylphenol concentrations varied, and higher levels were observed in sediment samples compared to water. Occurrence of NP ranged from 1.22 to 7.24 μg/l in water and 3.31 to 30.96 μg/kg in sediments.ConclusionTo our knowledge, this is the first report on the presence of NP in the marine environments of Chennai (Madras). This study alarms increase in the concentration of nonylphenol in the marine environments of Chennai coast as the measured values are several magnitudes higher than the environmental safety limit proposed by the US EPA.

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.

Determination of fats, oils and greases in food service establishment wastewater using a modification of the Gerber method

AbstractDischarges from food service establishments (FSEs) are a major source of fat, oil and grease (FOG) which cause blockages in sewer networks. Previous research has identified that current methods are unsuitable for quantifying FOG in FSE wastewater owing to interference from surfactants in detergents, and protein from food residuals which emulsify FOG. A novel quantification method, based on the dairy industry Gerber method, has been developed which negates the impact of surfactants. Moreover, the method allows free and emulsified oil to be quantified separately providing greater insight into FOG management strategies. Trials in synthetic and real FSE wastewaters indicate the novel method is more reliable than standard liquid–liquid and solid phase extraction in FOG‐rich systems.

Conventional and supercritical fluid extraction (SFE) of colchicine from Colchicum speciosum

This study was designed to investigate colchicine extraction from Colchicum speciosum L. using traditional and supercritical fluid extraction (SFE). The aim of this study was to i) optimize a new economical conventional liquid phase extraction procedure ii) optimize a supercritical fluid extraction (SFE) method to obtain a colchicine rich extract from C. speciosum. The seeds were defatted first and almost 7.92% oil was obtained from the extraction with 150 mL petroleum ether. The seeds were then used for both conventional and SFE extraction. The remaining solid was subjected to extraction with 95:5 methanol-water mixture (100, 150, 200, 250 and 300 mL) for 24 h by shaking the extract. The shaking process was also investigated for 1, 2, 3, 4, 5, 6 and 12 h shaking periods. The highest extract yield was obtained with 200 mL solvent. Although quantitative extract yield of 24 h was the highest (4.12%) 5, to 12 h shaking provided significant yields (approx. 3.60%). The concentration of colchicine derivatives was monitored by HPLC analysed using and presence of colchicoside, 3-demethylcolchicine and colchicine was confirmed. Colchicine content varied 0.17-0.26% depending on solvent volume and shaking period. SFE method (35 Co, CO2 flow rate: 1.50 mL/min., CO2 density: 0.90 g/mL, 247 bar) involving methanol modifier was investigated for 0.06, 0.2, 0.3, 0.4, 0.5 and 0.6 mL/min modifier flow rate. The extract yield was lower (1.44%) but contained only colchicine and an unknown compound which had identical DAD spectrums. 0.5 mL/min methanol modified SFE of C. speciosum seeds is highly effective for selective extraction of colchicine.

Optimising the detection of marine taxonomic richness using environmental DNA metabarcoding: the effects of filter material, pore size and extraction method

The analysis of environmental DNA (eDNA) using metabarcoding has increased in use as a method for tracking biodiversity of ecosystems. Little is known about eDNA in marine human-modified environments, such as commercial ports, which are key sites to monitor for anthropogenic impacts on coastal ecosystems. To optimise an eDNA metabarcoding protocol in these environments, seawater samples were collected in a commercial port and methodologies for concentrating and purifying eDNA were tested for their effect on eukaryotic DNA yield and subsequent richness of Operational Taxonomic Units (OTUs). Different filter materials [Cellulose Nitrate (CN) and Glass Fibre (GF)], with different pore sizes (0.5 µm, 0.7 µm and 1.2 µm) and three previously published liquid phase extraction methods were tested. The number of eukaryotic OTUs detected differed by a factor of three amongst the method combinations. The combination of CN filters with phenol-chloroform-isoamyl alcohol extractions recovered a higher amount of eukaryotic DNA and OTUs compared to GF filters and the chloroform-isoamyl alcohol extraction method. Pore size was not independent of filter material but did affect the yield of eukaryotic DNA. For the OTUs assigned to a highly successful non-indigenous species, Styelaclava, the two extraction methods with phenol significantly outperformed the extraction method without phenol; other experimental treatments did not contribute significantly to detection. These results highlight that careful consideration of methods is warranted because choice of filter material and extraction method create false negative detections of marine eukaryotic OTUs and underestimate taxonomic richness from environmental samples.

Determination of ochratoxin A in grape juice and wine using nanosponge solid phase extraction clean-up and liquid chromatography with fluorescence detection

Ochratoxin A is mycotoxin that can contaminate a variety of agricultural commodities, including fruit juices and wines. A detection method of ochratoxin A in grape juice and wine is reported that utilizes β-cyclodextrin, polyurethane nanosponge materials for solid phase extraction clean-up of beverage samples. Infrared analysis indicated a highly cross-linked structure that correspond with vibrational frequency analysis of PM6 semi-empirical computational models. Analysis of the material through atomic force microscopy (AFM) indicated nano-sized morphological features. A liquid chromatography method using fluorescence detection (LC-FLD) was capable of detecting ochratoxin A levels below regulatory levels in grape juice and wine. The recoveries of spiked ochratoxin A (0.5–20 ng mL−1) were between 77.0–89.4% in wine and 69.1–86.5% in grape juice.

Continuous in Situ Extraction toward Multiphase Complex Systems Based on Superwettable Membrane with Micro-/Nanostructures.

Liquid-phase extraction is widely used in the chemical industry. Traditional extracting routes always involve multiple procedures, need a large floor space, and have long operating time. "Continuous in situ extraction" that can conduct a real-time integration of solutes extraction and solvents separation simultaneously would be of great significance. Superwettable materials offer us a good choice to separate different immiscible solvents; herein, we achieve continuous in situ extraction of multiphase complex systems by using a porous polytetrafluoroethylene membrane with nanostructure-induced superwettability. It realizes a rapid, selective, and efficient real-time removal of various extracting agents during a continuous process due to their wetting differences. Compared with traditional extraction, our route shows a distinct superiority on saving operating time, enhancing liquid recovery, and simplifying procedures, while still retaining high extracting performance. In addition, our membrane possesses excellent durability even after long-term work in harsh chemical environments or under strong mechanical impacts. Thus, we believe that it will provide a potential alternative for current industrial extractions.

Determination of vitamin K composition of fermented food

A rapid ultra-high performance liquid chromatography–atmospheric pressure chemical ionization tandem mass spectrometric (UHPLC-APCI-MS/MS) method was developed for the analysis of vitamin K compounds: phylloquinone (PK) and menaquinones (MK-n). Non-chlorinated mobile phase composition was optimized for separation of eight vitamin K compounds on a reversed phase column in 10 min. Sample treatment with liquid and solid phase extractions and by the use of MK-4 as an internal standard enabled the quantitation of microgram level of vitamin K compounds in food. The method was used to screen and quantitate vitamin K from 17 fermented food products. The highest amount of PK was detected in kimchi (42 µg/100 g), whereas the highest MK-7 content was detected in natto (902 µg/100 g). Some MK-9 was present in kefir (5 µg/100 g). Two Chinese fermented soybean pastes contained significant amount of MK-6 (5–36 µg/100 g), MK-7 (12–86 µg/100 g), and MK-8 (22–44 µg/100 g).

Rapid determination of Alternaria mycotoxins in tomato samples by pressurised liquid extraction coupled to liquid chromatography with fluorescence detection

ABSTRACTA sensitive and reliable method using pressurised liquid extraction (PLE) followed by molecularly imprinted solid phase extraction (MISPE) and high performance liquid chromatography with fluorescence detection (HPLC–FLD) has been developed for the analysis of alternariol (AOH) and alternariol monomethyl ether (AME) in tomato samples. Influence of several extraction parameters that affect PLE efficiency were evaluated for the simultaneous extraction of both mycotoxins in the selected samples. AOH and AME were optimally extracted using MeOH/water (25:75, v/v) at 70°C as solvent, a pressure of 1000 psi and a single extraction cycle. The resulting PLE extracts were pre-concentrated by molecularly imprinted solid phase extraction (MISPE) cartridges followed of analysis by HPLC with fluorescence detection (λexc = 258, λem = 440 nm). The proposed method was applied to the analysis of AOH and AME in fortified tomato samples (20–72 µg· kg–1) with recoveries of 84–97% (RSD < 8%, n = 6) for AOH and 67–91% (RSD < 13%, n = 6) for AME. The detection limit for AOH and AME were 7 and 15 µg· kg–1, respectively. The ensuing PLE–MISPE–HPLC–FLD method was validated for the analysis of both mycotoxins in tomato samples in accordance with European Commission Decision 2002/657/EC.

Selective Process To Extract High-Quality Reduced Graphene Oxide Leaflets

One popular approach to prepare graphene on a large scale consists of converting graphene oxide (GO) into reduced graphene oxide (RGO). However, this procedure yields graphene flakes with various amounts of oxygenated defects. Using a double liquid phase extraction technique (DLPE) assisted by cholesterol-based polymers, we demonstrate that the RGO flakes of the highest quality, i.e., those with the highest π-conjugated network and with the lowest number of oxygenated defects, can be selectively extracted in isooctane, while lower quality flakes remain in water. Thus, it is possible to collect single-layer graphene sheets of high quality, as characterized by Raman spectroscopy (ID/IG below 0.2) starting from a RGO containing a heterogeneous mixture of leaflets (ID/IG ∼ 1.3). The high quality of the RGO leaflets extracted by DLPE was also confirmed by X-ray photoelectron spectroscopy, photoluminescence, Fourier transform infrared spectroscopy, X-ray diffraction, and atomic force microscopy. The conductivit...

Determination of selected emerging contaminants in freshwater invertebrates using a universal extraction technique and liquid chromatography accurate mass spectrometry.

A simple sample preparation method based on a modified liquid-phase extraction approach to extract selected pharmaceuticals and personal care products from freshwater organisms is described. Extracted samples were analysed using liquid chromatography with Q-Exactive plus hybrid quadrupole Orbitrap mass spectrometry, using 2.6 μm C18 media. A 0.1% v/v acetic acid/acetonitrile mobile phase was applied over a 20min gradient. Method detection limits in full scan mode were ca. 0.04-2.38ng of analyte per g of sample. Linearity ranged from 0.9750 to 0.9996 over the calibration range of 0.01-100μg/L; MS mass accuracy was <2ppm for most analytes. This method was applied to quantify six pharmaceuticals and personal care products in seven invertebrate samples. For tandem mass spectrometry analysis, selection of precursor ions was performed for each pharmaceutical, with Mass Frontier software illustrating the fragmentation mechanism. Effects of collision energy on intensities of ions was further investigated. The tandem mass spectrometry condition resulting in the highest signal of respective selected product ion was selected to confirm each pharmaceutical, which was initially observed in the full scan mode. Results indicate that pharmaceuticals and personal care products found to be present in water-ways, may be incorporated into organisms that live in the environment of affected water streams.

Determination of Paraquat in Environmental Water by Ionic Liquid-Based Liquid Phase Extraction with Direct Injection for HPLC

A simple method for the determination of paraquat in environment samples was developed. 1‑Ethyl-3-methylimidazolium ethyl sulfate and anhydrous potassium hydrogen phosphate were used to form aqueous two-phase system. The system was applied to the extraction of paraquat and its determination by HPLC. To achieve optimum extraction performance, several experimental parameters, including the type and the amount of salt, the amount of ionic liquid, extraction time, were investigated and optimized. Under the optimal experimental conditions, good linearity was observed in the range of 10–5 × 103 ng/mL. The limit of detection was 8 ng/mL along with enrichment factor of 18. The phase behavior of aqueous two-phase system and extraction mechanism were investigated by UV-Vis spectroscopy. The present method was successfully applied to the determination of paraquat in environment samples, and the recovery was in the range of 92.3–95.1%. The results showed that the present method is rapid, feasible and environmentally friendly.

Simultaneous HPLC-ELSD determination of sugars and cyclitols in different parts of Phacelia tanacetifolia Benth.

Three cyclitols (allo-inositol, scyllo-inositol and myo-inositol) and seven sugars (xylose, d-mannose, d-glucose, sucrose, D-(+)-turanose, D-(+)-melezitose monohydrate and D-(+)-raffinose pentahydrate) were determined in different morphological parts of lacy phacelia by high performance liquid chromatography-evaporative light scattering detector (HPLC-ELSD) method in 30 min. The applied analytical method is rapid, simple, sensitive, low cost, reliable and suitable for profiling of major sugars and cyclitols in Phacelia tanacetifolia Benth. (lacy phacelia) parts. Pressurized liquid extraction and solid phase extraction were used as extraction and purification methods. The obtained results showed significant differences in the quantities and distribution of cyclitols and sugars found in the investigated morphological parts. The quantities of the identified cyclitols in lacy phacelia ranged between 1.07 and 4.68 mg/g of dried plant, while for sugars in the range of 1.07–25.3 mg/g. However, flowers were richer in cyclitols and sugars compared to the seeds.

Liquid phase extraction and separation of natural compounds

ELECTROPHORESISVolume 39, Issue 15 p. 1833-1834 Editorial Liquid phase extraction and separation of natural compounds Elena Ibáñez, Elena IbáñezSearch for more papers by this authorMiguel Herrero, Miguel HerreroSearch for more papers by this author Elena Ibáñez, Elena IbáñezSearch for more papers by this authorMiguel Herrero, Miguel HerreroSearch for more papers by this author First published: 02 August 2018 https://doi.org/10.1002/elps.201870124Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume39, Issue15Special Issue: Liquid phase extraction and separation of natural compoundsAugust 2018Pages 1833-1834 RelatedInformation

Liquid phase extraction and separation of natural compounds

Liquid phase extraction and separation of natural compounds

Liquid phase extraction of nanosized biologically active estrogenic pollutants by using an efficient adsorbent

Dangerous nanosized micropollutants and estrogenic hormones which might severely affect the environment are more found in water effluents, recently, and detection of them is of high importance. As the result, reliable and inexpensive absorptive extraction and removal applications are favored. As the second most abundant biomolecule on earth, a lignocellulosic material can be a potential choice as nanosized adsorbent. In this paper, quantum chemistry techniques are employed as the state of the art approach for predictive modeling, to investigate the feasibility of using this material in extraction and removal of eight estrogens including estradiol, estrone, testosterone, progesterone, estriol, mestranol, ethinylestradiol and diethylstilbestrol. Due to nano-scaled dimensions of these pollutants, removing them by using current commercial methods is challenging and a new approach needed to be developed. The mechanism of removing micropollutants from water affluent is based on adsorption. This fact motivated us to simulate the adsorption process, and check how well the adsorbent interact with nanosized micropollutants. In order to evaluate the affinity of lowest energy sites on structure of the lignocellulosic material toward each estrogenic hormones and micropollutants, we carried out configurational bias Monte Carlo search of the configurational space of the lignocellulosic material-estrogenic micropollutants systems according to a simulated annealing schedule. To check the response and sensitivity of the lignocellulosic material to each estrogenic micropollutants, a combination of modified Flory-Huggins model and molecular simulation techniques was used. Evaluation of detachment energy revealed the potential of the lignocellulosic material as a reusable material for removing these compounds in an aqueous media.

Recent Advances in Applications of Ionic Liquids in Miniaturized Microextraction Techniques.

Green sample preparation is one of the most challenging aspects in green analytical chemistry. In this framework, miniaturized microextraction techniques have been developed and are widely performed due to their numerous positive features such as simplicity, limited need for organic solvents, instrumentation of low cost and short time of extraction. Also, ionic liquids (ILs) have unequivocally a “green” character, which they owe to their unique properties including the re-usage, the high reaction efficiency and selectivity in room temperature, the ability to dissolve both organic and inorganic compounds, and thermal stability. In the present review, the recent advances in the application of ionic liquids in miniaturized liquid and solid phase extraction techniques as extractants, intermediate solvents, mediators and desorption solvents are discussed, quoting the advantages and drawbacks of each individual technique. Some of the most important sample preparation techniques covered include solid-phase microextraction (SPME), dispersive liquid-liquid microextraction (DLLME), single-drop microextraction (SDME), stir bar sorptive extraction (SBSE), and stir cake sorptive extraction (SCSE).