Journal articles: 'Extractions SPE'

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Tartaglia, Angela, Marcello Locatelli, Abuzar Kabir, Kenneth G. Furton, Daniela Macerola, Elena Sperandio, Silvia Piccolantonio, et al. "Comparison between Exhaustive and Equilibrium Extraction Using Different SPE Sorbents and Sol-Gel Carbowax 20M Coated FPSE Media." Molecules 24, no. 3 (January 22, 2019): 382. http://dx.doi.org/10.3390/molecules24030382.

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This paper reports the performance comparison between the exhaustive and equilibrium extraction using classical Avantor C18 solid phase extraction (SPE) sorbent, hydrophilic-lipophilic balance (HLB) SPE sorbent, Sep-Pak C18 SPE sorbent, novel sol-gel Carbowax 20M (sol-gel CW 20M) SPE sorbent, and sol-gel CW 20M coated fabric phase sorptive extraction (FPSE) media for the simultaneous extraction and analysis of three inflammatory bowel disease (IBD) drugs that possess logP values (polarity) ranging from 1.66 for cortisone, 2.30 for ciprofloxacin, and 2.92 for sulfasalazine. Both the commercial SPE phases and in-house synthesized sol-gel CW 20M SPE phases were loaded in SPE cartridges and the extractions were carried out under an exhaustive extraction mode. FPSE was carried out under an equilibrium extraction mode. The drug compounds were resolved using a Luna C18 column (250 mm × 4.6 mm; 5 m particle size) in gradient elution mode within 20 min and the method was validated in compliance with international guidelines for the bioanalytical method validation. Novel in-house synthesized and loaded sol-gel CW 20M SPE sorbent cartridges were characterized in terms of their extraction capability, breakthrough volume, retention volume, hold-up volume, number of the theoretical plate, and the retention factor.

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Zou, Wei, Chris Lusk, Dale Messer, and Ralph Lane. "Fat Contents of Cereal Foods: Comparison of Classical with Recently Developed Extraction Techniques." Journal of AOAC INTERNATIONAL 82, no. 1 (January 1, 1999): 141–50. http://dx.doi.org/10.1093/jaoac/82.1.141.

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Abstract Eight cereal products ranging from a fat-free ready- to-eat (RTE) cereal (frosted flakes) to a full-fat high- ratio cake mix were subjected to analyte separation by anhydrous diethyl ether extraction (EE), acid hydrolysis/mixed ether extraction (AH), solid-phase extraction (SPE), and supercritical fluid extraction (SFE) with CO2 and with CO2 modified with 15% ethanol (SFEmod). Gravimetric analyses of extracts indicated higher (P ≤ 0.05) crude fat values by AH than by EE, SFE, or SFEmod. Extractions followed by fatty acid methyl ester analysis also produced higher (P ≤ 0.05) triglyceride means by AH than by other methods used for heat-treated RTE cereals and for ready-to-cook (RTC) cream of wheat. Therefore, for labeling purposes, AH seems most appropriate because in most cases it achieves higher triglyceride values than extraction with solvent(s) alone. SFE and SPE, on the other hand, yield fat values similar to those obtained by EE and offer the advantages of reduced solvent volume, short extraction times, and ease of laboratory automation.

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Vieira, Eny M., and Francis I. Onuska. "Extraction and Determination of RDX and HMX in Water." Water Quality Research Journal 34, no. 3 (August 1, 1999): 533–44. http://dx.doi.org/10.2166/wqrj.1999.026.

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Abstract The analysis of energetic materials such as RDX and HMX in water at trace levels was accomplished by using micro-extraction by miscible solvents, such as acetonitrile, 2-propanol and acetone, and salting out the organic phase. This paper compares the results obtained with solid-phase extraction (SPE) to those obtained by demixing techniques for spiked Milli-Q water and an unfiltered lake water. A review of the data indicates that demixing with acetonitrile-sodium chloride and 2-propanol ammonium sulfate gives better extraction recoveries than solid-phase extraction. Salting-out extractions are performed in less time and with less solvent than by SPE techniques.

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Yung An, Chua, Md Murad Hossain, Fahmida Alam, Md Asiful Islam, Md Ibrahim Khalil, Nadia Alam, and Siew Hua Gan. "Efficiency of Polyphenol Extraction from Artificial Honey Using C18 Cartridges and Amberlite® XAD-2 Resin: A Comparative Study." Journal of Chemistry 2016 (2016): 1–6. http://dx.doi.org/10.1155/2016/8356739.

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A comparative study of the extraction efficiency of nine known polyphenols [phenolic acids (benzoic acid, dihydroxybenzoic acid, gallic acid, trans-cinnamic acid, and vanillic acid) and flavonoids (naringenin, naringin, quercetin, and rutin)] was conducted by deliberately adding the polyphenols to an artificial honey solution and performing solid phase extraction (SPE). Two SPE methods were compared: one using Amberlite XAD-2 resin and another one using a C18 cartridge. A gradient high performance liquid chromatography system with an RP18 column and photodiode array detector was utilized to analyze the extracted polyphenols. The mean percent of recovery from the C18 cartridges was 74.2%, while that from the Amberlite XAD-2 resin was 43.7%. The recoveries of vanillic acid, naringin, and rutin were excellent (>90%); however, gallic acid was not obtained when C18 cartridges were used. Additionally, the reusability of Amberlite XAD-2 resin was investigated, revealing that the mean recovery of polyphenols decreased from 43.7% (1st extraction) to 29.3% (3rd extraction). It was concluded that although Amberlite XAD-2 resin yielded a higher number of compounds, C18 cartridges gave a better extraction recovery. The lower recovery seen for the Amberlite XAD-2 resin also cannot be compensated by repeated extractions due to the gradual decrease of extraction recovery when reused.

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Shyam Sunder, Govind Sharma, Sandhya Adhikari, Ahmad Rohanifar, Abiral Poudel, and Jon R. Kirchhoff. "Evolution of Environmentally Friendly Strategies for Metal Extraction." Separations 7, no. 1 (January 6, 2020): 4. http://dx.doi.org/10.3390/separations7010004.

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The demand for the recovery of valuable metals and the need to understand the impact of heavy metals in the environment on human and aquatic life has led to the development of new methods for the extraction, recovery, and analysis of metal ions. With special emphasis on environmentally friendly approaches, efforts have been made to consider strategies that minimize the use of organic solvents, apply micromethodology, limit waste, reduce costs, are safe, and utilize benign or reusable materials. This review discusses recent developments in liquid- and solid-phase extraction techniques. Liquid-based methods include advances in the application of aqueous two- and three-phase systems, liquid membranes, and cloud point extraction. Recent progress in exploiting new sorbent materials for solid-phase extraction (SPE), solid-phase microextraction (SPME), and bulk extractions will also be discussed.

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Zuin, Vânia G., Vitaliy L. Budarin, Mario De bruyn, Peter S. Shuttleworth, Andrew J. Hunt, Camille Pluciennik, Aleksandra Borisova, Jennifer Dodson, Helen L. Parker, and James H. Clark. "Polysaccharide-derived mesoporous materials (Starbon®) for sustainable separation of complex mixtures." Faraday Discussions 202 (2017): 451–64. http://dx.doi.org/10.1039/c7fd00056a.

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The recovery and separation of high value and low volume extractives are a considerable challenge for the commercial realisation of zero-waste biorefineries. Using solid-phase extractions (SPE) based on sustainable sorbents is a promising method to enable efficient, green and selective separation of these complex extractive mixtures. Mesoporous carbonaceous solids derived from renewable polysaccharides are ideal stationary phases due to their tuneable functionality and surface structure. In this study, the structure–separation relationships of thirteen polysaccharide-derived mesoporous materials and two modified types as sorbents for ten naturally-occurring bioactive phenolic compounds were investigated. For the first time, a comprehensive statistical analysis of the key molecular and surface properties influencing the recovery of these species was carried out. The obtained results show the possibility of developing tailored materials for purification, separation or extraction, depending on the molecular composition of the analyte. The wide versatility and application span of these polysaccharide-derived mesoporous materials offer new sustainable and inexpensive alternatives to traditional silica-based stationary phases.

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Bianchi, Sauro, Gerald Koch, Ron Janzon, Ingo Mayer, Bodo Saake, and Frédéric Pichelin. "Hot water extraction of Norway spruce (Picea abies [Karst.]) bark: analyses of the influence of bark aging and process parameters on the extract composition." Holzforschung 70, no. 7 (July 1, 2016): 619–31. http://dx.doi.org/10.1515/hf-2015-0160.

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Abstract The hot water (HW) extraction of Norway spruce (Picea abies [Karst.]) delivers condensed tannins and considerable amounts of other compounds. Yield and composition of the HW extracts were investigated as a function of natural weathering for up to 15 months. Total phenol monomers and oligomers were detected by Folin-Ciocaltau assay after fractionation by solid phase extraction (SPE). Procyanidins (PC) were determined by HPLC-UV after acid thiolysis and carbohydrates by HPLC combined with acid hydrolysis. Topochemistry of the bark before and after extraction was investigated by UV-microspectrometry (UMSP) and non-extractable PC analyzed by direct thiolysis on the bark. The influence of the parameters on the yield and composition of the extracts were evaluated, such as the extraction temperature, time and the addition of sodium sulfate and urea. Prolonged weathering resulted in a considerable decrease of the total extraction yield, partly because of leaching of phenolic monomers, mono- and oligosaccharides. The yield of phenolic oligomers also decreased at a moderate rate, while the yield of polysaccharides (pectins) was almost stable. Non-extractable and non-leachable compounds deposited in the cell lumens represent the majority of the phenolic extractives in spruce bark. Sequential extractions performed at increasing temperature proved to be a suitable method for the recovery of tannin-rich extracts.

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Kraševec, Ida, and Helena Prosen. "Solid-Phase Extraction of Polar Benzotriazoles as Environmental Pollutants: A Review." Molecules 23, no. 10 (September 29, 2018): 2501. http://dx.doi.org/10.3390/molecules23102501.

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Polar benzotriazoles are corrosion inhibitors with widespread use; they are environmentally characterized as emerging pollutants in the water system, where they are present in low concentrations. Various extraction methods have been used for their separation from various matrices, ranging from classical liquid–liquid extractions to various microextraction techniques, but the most frequently applied extraction technique remains the solid-phase extraction (SPE), which is the focus of this review. We present an overview of the methods, developed in the last decade, applied for the determination of benzotriazoles in aqueous and solid environmental samples. Several other matrices, such as human urine and plant material, are also considered in the text. The methods are reviewed according to the determined compounds, sample matrices, cartridges and eluents used, extraction recoveries and the achieved limits of quantification. A critical evaluation of the advantages and drawbacks of the published methods is given.

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Bajkacz, Sylwia, Jakub Adamek, and Anna Sobska. "Application of Deep Eutectic Solvents and Ionic Liquids in the Extraction of Catechins from Tea." Molecules 25, no. 14 (July 14, 2020): 3216. http://dx.doi.org/10.3390/molecules25143216.

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This work aimed to comprehensively evaluate the potential and effectiveness of deep eutectic solvents (DESs) in the extraction of seven catechins from various tea samples. Different combinations of DES were used, consisting of Girard’s reagent T (GrT) in various mixing ratios with organic acids and choline chloride. The yields of the DES extractions were compared with those from ionic liquids and conventional solvent. DES contained malic acid, as the hydrogen bond donors showed a good solubility of catechins with different polarities. In the second part of the study, a solid-phase extraction (SPE) method was applied to the extraction of catechins from tea infusions. The method was applied to the determination of selected catechins in tea leaves and tea infusions. Furthermore, we demonstrated that the proposed procedure works well in the simultaneous monitoring of these polyphenols, which makes it a useful tool in the quality control of tea.

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Makowicz, Ewa, Izabela Jasicka-Misiak, Dariusz Teper, and Paweł Kafarski. "HPTLC Fingerprinting—Rapid Method for the Differentiation of Honeys of Different Botanical Origin Based on the Composition of the Lipophilic Fractions." Molecules 23, no. 7 (July 21, 2018): 1811. http://dx.doi.org/10.3390/molecules23071811.

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Bee honey possess various nutritional and medicinal functions, which are the result of its diverse chemical composition. The numerous bioactive compounds in honey come from flower nectar; thus, the identification of the specific chemical profiles of honey samples is of great importance. The lipophilic compounds from eight monofloral honeys (rape, buckwheat, clover, willow, milk thistle, dandelion, raspberry and sweet yellow clover) were investigated. Analyses of the lipophilic fractions obtained by UAE (ultrasound assisted extraction) and SPE (solid phase extraction) extractions were performed using high-performance thin layer chromatography (HPTLC). Chromatographic and cluster analyses allowed the identification of a unique, colorful pattern of separated compounds with specific Rf values on the HPTLC plate for each type of monofloral honey. HPTLC is a simple and effective visual method of analysis, and it can serve as a basis for authenticating different types of honey.

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Piqani, Bruno, and Wei Zhang. "Synthesis of diverse dihydropyrimidine-related scaffolds by fluorous benzaldehyde-based Biginelli reaction and post-condensation modifications." Beilstein Journal of Organic Chemistry 7 (September 16, 2011): 1294–98. http://dx.doi.org/10.3762/bjoc.7.150.

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Dihydropyrimidinones and dihydropyrimidinethiones generated from the Biginelli reactions of perfluorooctanesulfonyl-attached benzaldehydes are used as common intermediates for post-condensation modifications such as cycloaddition, Liebeskind–Srogl reaction and Suzuki coupling to form biaryl-substituted dihydropyrimidinone, dihydropyrimidine, and thiazolopyrimidine compounds. The high efficiency of the diversity-oriented synthesis is achieved by conducting a multicomponent reaction for improved atom economy, under microwave heating for fast reaction, and with fluorous solid-phase extractions (F-SPE) for ease of purification.

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Veach, Brian T., Chris A. Baker, John H. Kibbey, Andrew Fong, Bryanna J. Broadaway, and Connie P. Drake. "Quantitation of Chloramphenicol and Nitrofuran Metabolites in Aquaculture Products Using Microwave-Assisted Derivatization, Automated SPE, and LC-MS/MS." Journal of AOAC INTERNATIONAL 98, no. 3 (May 1, 2015): 588–94. http://dx.doi.org/10.5740/jaoacint.14-271.

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Abstract This paper describes a rapid and robust method utilizing microwave-assisted derivatization, automated SPE, and LC-MS/MS for the quantitation and confirmation of chloramphenicol (CAP) and nitrofuran metabolites in various aquaculture matrixes. The use of equipment presented in this work allowed extractions to be completed on average within 6 h, with quantitation accuracy ranging from 89 to 107% and RSD ≤8.3%. The demonstrated detection limits for all the nitrofuran metabolites of interest in three different matrixes were ≤0.06 ng/g, with a quantitation limit of ≤0.2 ng/g. Additionally, the method exhibited a CAP detection limit for all matrixes ≤0.01 ng/g and an LOQ of ≤0.03 ng/g.

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Dussault, Ève B., Vimal K. Balakrishnan, Keith R. Solomon, and Paul K. Sibley. "Matrix effects on mass spectrometric determinations of four pharmaceuticals and personal care products in water, sediments, and biota." Canadian Journal of Chemistry 87, no. 5 (May 2009): 662–72. http://dx.doi.org/10.1139/v09-042.

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Simple analytical methods were developed for the extraction and determination of four pharmaceuticals and personal care products (PPCPs) from water, sediments, and biota. PPCPs were determined using tandem LC–MS in electrospray ionization mode, and interactions with matrix co-eluents were investigated. Extractions of water samples were performed using solid-phase extraction (SPE), sediments were extracted by pressurized liquid extraction (PLE), and biota was extracted by liquid extraction. The selected analytical methods yielded recoveries ≥ 61% in all matrixes. Matrix interactions were investigated throughout the linear range of quantification of each compound, revealing that dissolved salts had relatively minor effects on ionization (between 14% suppression to 12% enhancement), but that sediment and biota extracts caused significant matrix effects (ranging from 56% suppression to 25% enhancement). The direction and magnitude of matrix interactions reflected the physico-chemical properties of each analyte, particularly their pKa. Among the compounds analyzed in electrospray positive mode, carbamazepine was insensitive to matrix interactions, because it is a strong proton acceptor (pKa = 14.0). In contrast, atorvastatin (pKa = 4.5), a weaker proton acceptor, was particularly sensitive to matrix effects. For those compounds analyzed in negative-ion mode, sample alkalinity was found to be important. With a pKa of 10.4, 17α-ethinylestradiol generally exhibited matrix enhancement with increased sample alkalinity. However, the presence of acidic co-eluents contributed to matrix suppression. Lastly, TCS was particularly sensitive to matrix suppression, as its circumneutral pKa (7.9) caused even slight changes in sample pH to considerably impact ionization. We conclude that while different matrixes have clear impacts on ionization of these PPCPs, matrix effects can be quantified and overcome.

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Facorro, Rocio, Maria Llompart, and Thierry Dagnac. "Combined (d)SPE-QuEChERS Extraction of Mycotoxins in Mixed Feed Rations and Analysis by High Performance Liquid Chromatography-High-Resolution Mass Spectrometry." Toxins 12, no. 3 (March 23, 2020): 206. http://dx.doi.org/10.3390/toxins12030206.

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The objective of this work was the development of a methodology capable of simultaneously determine 26 mycotoxins in mixed feed rations collected in 20 dairy farms. A sample preparation methodology based on a combination of (d)SPE and QuEChERS extractions was used. Liquid chromatography-high resolution mass spectrometry was employed for both identification and quantification purposes. To this respect, a powerful workflow based on data-independent acquisition, consisting of fragmenting all precursor ions entering the mass spectrometer in narrow m/z isolation windows (SWATH), was implemented. SWATH data file then contains all the information that would be acquired in a multitude of different experimental approaches in a single all-encompassing dataset. Analytical method performance was evaluated in terms of linearity, repeatability and matrix effect. Relative recoveries were also measured, giving values above 80% for most compounds. Matrix-matched calibration was carried out and enabled reaching the low ng mL−1 level for many mycotoxins. The observed matrix effect, in most cases suppressive, reached even values higher than 60%. The repeatability was also adequate, showing a relative standard deviation lower than 10%. All unified samples analyzed showed co-occurrence of two or more mycotoxins, recurrently zearalenone, fumonisin B1, and β-zearalenol, with an occurrence frequency ranging from 60% to 90%.

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España Orozco, Sebastian, Philipp Zeitlinger, Karin Fackler, Robert H. Bischof, and Antje Potthast. "A solid-phase extraction method that eliminates matrix effects of complex pulp mill effluents for the analysis of lipophilic wood extractives." Nordic Pulp & Paper Research Journal 35, no. 4 (November 18, 2020): 577–88. http://dx.doi.org/10.1515/npprj-2020-0039.

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AbstractThe extraction of lipophilic wood extractives from pulp and paper process waters proves to be a challenging task, due to harsh and alternating process and sample conditions. This study has determined the potential use of polymeric sorbents for solid-phase extraction (SPE) and compared to classical silica-based reversed-phase packed columns, with polymeric hydrophilic-lipophilic balanced (HLB) cartridges being the sorbent with the most potential. Recovery functions were obtained with an internal standard mixture representative for the main lipophilic wood extractive groups, which are fatty acids and alcohols, sterols, sterol esters and triglycerides. The impact of pH, sample volume and sample matrix, expressed as TOC and cations, on the retention behavior of lipophilic extractives during SPE of industrial samples were determined with polymeric HLB sorbent. High variations in the composition of pulp mill matrices led to different optimal extraction conditions. Thus, a new SPE protocol was developed, which bypasses matrix interferences and omits the loss of analytes due to sample preparation. The method is applicable to different pulp mill effluents with large discrepancies in pH and sample matrices, resulting in recoveries >90 % with RSD <5 % for all lipophilic wood extractives.

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Nagy, Júlia, and Tibor Veress. "Systematic Error for Extraction of Controlled Substances from Plant/Fungal Materials." Journal of Chromatographic Science 58, no. 10 (September 18, 2020): 985–91. http://dx.doi.org/10.1093/chromsci/bmaa067.

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Abstract The aim of this work was to investigate the applicability of a mathematical model developed for the description of supercritical fluid extraction (SFE) of cannabinoids from marijuana and hashish for liquid extraction of other substances. The mentioned model is applicable for dynamic SFE whose implementation is analogous to liquid–solid extraction in quasi-counter current mode. According to this model, quasi-counter current liquid–solid extractions were designed by calculation of component transport constants for extractions of psilocin from hallucinogenic mushroom, mescaline from hallucinogenic cactus, harmine from tropical lyan and salvinorin A from hallucinogenic sage. The mentioned model was found to be suitable for the determination of extraction time needed to reach a predefined extraction recovery for quasi-counter current liquid–solid extractions, as well, which allows the elimination of systematic error caused by the non-extracted part. The calculated component transport constants predict the expectable velocity of the extraction, i.e., the higher the component transport constant is, the higher the extraction velocity is. For mushrooms, it could be stated that preliminary treatment of mushrooms with liquid nitrogen significantly increases the extractability of psilocin.

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Lee, Kwang Jin, Jin Yeul Ma, Young Jun Kim, and Young Sik Kim. "Solid Phase Extraction(SPE) of Curcuminoids from Turmeric by Optimization Analytical Condition." Journal of the Korea Academia-Industrial cooperation Society 13, no. 10 (October 31, 2012): 4927–35. http://dx.doi.org/10.5762/kais.2012.13.10.4927.

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Rodrigues, Vítor H., Marcelo M. R. de Melo, Inês Portugal, and Carlos M. Silva. "Extraction of Added-Value Triterpenoids from Acacia dealbata Leaves Using Supercritical Fluid Extraction." Processes 9, no. 7 (July 3, 2021): 1159. http://dx.doi.org/10.3390/pr9071159.

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Forestry biomass is a by-product which commonly ends up being burnt for energy generation, despite comprising valuable bioactive compounds with valorisation potential. Leaves of Acacia dealbata were extracted for the first time by supercritical fluid extraction (SFE) using different conditions of pressure, temperature and cosolvents. Total extraction yield, individual triterpenoids extraction yields and concentrations were assessed and contrasted with Soxhlet extractions using solvents of distinct polarity. The extracts were characterized by gas chromatography coupled to mass spectrometry (GC-MS) and target triterpenoids were quantified. The total extraction yields ranged from 1.76 to 11.58 wt.% and the major compounds identified were fatty acids, polyols, and, from the triterpenoids family, lupenone, α-amyrin and β-amyrin. SFE was selective to lupenone, with higher individual yields (2139–3512 mg kgleaves−1) and concentrations (10.1–12.4 wt.%) in comparison to Soxhlet extractions, which in turn obtained higher yields and concentrations of the remaining triterpenoids.

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Fiddler, Walter, and John W. Pensabene. "Supercritical Fluid Extraction of Volatile N-Nitrosamines in Fried Bacon and Its Drippings: Method Comparison." Journal of AOAC INTERNATIONAL 79, no. 4 (July 1, 1996): 895–903. http://dx.doi.org/10.1093/jaoac/79.4.895.

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Abstract N-Nitrosopyrrolidine (NPYR) and N-nitrosodimethylamine (NDMA), known animal carcinogens, are consistently formed in bacon during frying. As a result, commercial bacon has been subject to regulatory monitoring and compliance for the past 20 years to ensure that N-nitrosamines do not exceed the 10 ppb violative level. Currently, time-consuming distillation-solvent extraction and solidphase extraction (SPE) methods are used for this purpose. With an emphasis on reducing solvent use, we investigated supercritical fluid extraction (SFE) using supercritical carbon dioxide (SC-CO2) for isolation of volatile nitrosamines common to fried bacon. Eighteen fried bacon samples were analyzed for NPYR and NDMA by SFE, SPE, mineral oil distillation (MOD), and low-temperature vacuum distillation (LTVD) methods, using the same gas chromatographic-chemiluminescence detection (thermal energy analyzer) conditions. The range of values for SFE was 0.7 to 20.2 ppb for NPYR and none detected (ND) to 2.4 ppb for NDMA. Analysis of variance of the NPYR data showed a significant difference (p < 0.05) between SFE and SPE results and significant differences between these and those obtained by MOD and LTVD. Overall, SFE was superior to the other methods with the highest recoveries, best repeatability, rapidity of analysis, and solvent-sparing characteristics. Similar results were obtained for SFE after comparison with distillation and SPE methods for determining the same nitrosamines in fried bacon drippings.

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Baynes, Ronald E., and John M. Bowen. "Rapid Determination of Methyl Parathion and Methyl Paraoxon in Milk by Gas Chromatography with Solid-Phase Extraction and Flame Photometric Detection." Journal of AOAC INTERNATIONAL 78, no. 3 (May 1, 1995): 812–14. http://dx.doi.org/10.1093/jaoac/78.3.812.

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Abstract Methyl parathion (MPT; O,O-dimethyl-O-4-nitro-phenyl phosphorothioate) and its active metabolite, methyl paraoxon (MPO; O, O-dimethyl-O-4-nitro-phenyl phosphate), were isolated from raw milk by solid-phase extraction (SPE) and determined by gas chromatography with flame photometric detection. The SPE method was compared with a traditional liquid-liquid extraction (LLE) procedure to determine whether SPE had suitable sensitivity and better efficiency in extracting MPT and MPO from milk of cows and goats. Method detection limits were higher for SPE, but the differences were not significant (t-test). Recoveries of MPT and MPO from raw milk samples spiked at 0.05, 0.5, and 5.0 pg/mL ranged from 80.0 to 118%, and the coefficients of variation were usually less than 10% for both methods. LLE required more organic solvents and was more time consuming compared with SPE.

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Sovilj, Milan, and Branislava Barjaktarovic. "Kinetics of the extraction of pumpkin seed oil (Cucurbita pepo L) by supercritical CO2." Chemical Industry 59, no. 9-10 (2005): 238–42. http://dx.doi.org/10.2298/hemind0510238s.

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This paper deals with the supercritical carbon dioxide extraction of pumpkin seed oil (Cucurbita pepo L). Supercritical fluid extraction (SFE) has been used to obtain total lipid extracts from other oilseeds, and it has also proved successful in the isolation and enrichment of sterols from oilseeds. The SFE of pumpkin seed oil on a laboratory scale was investigated in thus paper, with special interest in the influence of the extraction pressure on the overall yield of pumpkin seed oil. Extractions were carried out at the pressures of 15, 25 and 30 MPa and at 313 K, and at a pressure of 30 MPa and the temperatures 313, 323, and 333 K. The yield of the extractions conducted at 15 MPa was rather low, 0.1814 g oil per 1g of seed feed (18.4%) for an extraction time of 14 h. However, extractions at higher pressures yielded greater quantities of the oil; at 22.5 MPa for 9 h, 36.3% of the oil and at 30 MPa for 6 h, 41.0% of the oil. For comparison, hexane extraction of the seed material yielded less than 40% of the oil. Temperature did not influence the extraction yield. At a pressure of 30 MPa, the color of the fractions yielded during successive extraction time intervals varied greatly, from pail yellow (the first 2 h), through orange-yellow (from 2-4 h) to red (after 4 h). The experimental results of the oil yields were compared with the data obtained by the mathematical model of Hong et al., presented in the literature.

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Cao, Hui. "Comparison of extraction methods for the hypotensive drugs from Eucommia ulmoides." Archives of Biological Sciences 62, no. 3 (2010): 725–30. http://dx.doi.org/10.2298/abs1003725c.

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Extraction methods using Soxhlet extraction (SE), enzyme-assisted aqueous extraction (EE), semi-bionic extraction (SBE) and supercritical fluid extraction (SFE) were evaluated for the yields of geniposidic acid (GPA) and geniposide (GPS) from the bark of Eucommia ulmoides. The results showed that the yields of GPA and GPS attained by EE and SBE were highest, respectively. Compared with various extraction methods for the extraction of GPA and GPS, the SBE was more efficient than other methods. There was no organic solvent used in SBE. The pH values of semi-bionic extraction were the same as in the human body. The results indicate that SBE can be used for large-scale and efficient extraction of GPA and GPS from plant materials. The time taken by SFE was longer than other methods, but the yields of GPA and GPS were the lowest. .

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Borsotti, Angelo, and Ulya Trofimovich. "Efficient POSIX submatch extraction on nondeterministic finite automata." Software: Practice and Experience 51, no. 2 (October 18, 2020): 159–92. http://dx.doi.org/10.1002/spe.2881.

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Topçu, Aykut Arif, Süleyman Aşır, and Deniz Türkmen. "DNA Purification by Solid Phase Extraction (SPE) Methods." Hacettepe Journal of Biology and Chemistry 3, no. 44 (July 1, 2016): 259. http://dx.doi.org/10.15671/hjbc.20164420568.

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Humbert, Luc. "Extraction en phase solide (SPE) : théorie et applications." Annales de Toxicologie Analytique 22, no. 2 (2010): 61–68. http://dx.doi.org/10.1051/ata/2010010.

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Dai, Jinlan, Honglei Yin, Lingyun Yu, Tang Hong, Lei Zhou, and Minghua Liu. "Novel poly(β-cyclodextrin) porous material as solid phase extraction sorbent for aniline derivatives in rubber samples." BioResources 16, no. 3 (July 1, 2021): 5746–65. http://dx.doi.org/10.15376/biores.16.3.5746-5765.

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Aniline derivates are widely used in rubber products as anti-aging agents, but their biological toxicity causes harm in the use and recycling of rubber products. Therefore, in this study, a high-performance poly(3,4,5,6-tetra-fluorophthalonitrile-β-cyclodextrin)(P-TFPN-β-CD) solid-phase extraction (SPE) adsorbent was synthesized and applied to extract and detect aniline derivatives in rubber specimens. After crosslinking with 3,4,5,6-tetrafluorophthalonitrile (TFPN), the polymer exhibited mesopores (7.88 nm) and a large specific area (55.2 m2/g). The porous structure significantly improved the extraction efficiency (recovery was between 90.1% and 110.5%) and rate (60% in 10 s) of 4 aniline derivatives (aniline, N-ethyl aniline, 1,2-phenylenediamine, and p-phenylenediamine). With a combined gas chromatographic-flame ionization detector (GC-FID), the extracted aniline derivatives were accurately detected (RSD = 1.60% to 9.90%). Due to the weak interaction between P-TFPN-β-CD and analyte, the prepared poly-TFPN-β-CD SPE adsorbent was regenerated via mild washing with methanol. The high absorption capacities remained after 4 extracting-washing cycles. The novel porous SPE adsorbent showed good extracting and recycling performance for the analysis and detection of aniline compounds in rubber. Thus, it has good prospects for application to improve detection efficiency and reduce cost.

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Ducat, Tom. "Divisorial extractions from singular curves in smooth 3-folds." International Journal of Mathematics 27, no. 01 (January 2016): 1650005. http://dx.doi.org/10.1142/s0129167x16500051.

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Consider a singular curve [Formula: see text] contained in a smooth [Formula: see text]-fold [Formula: see text]. Assuming the general elephant conjecture, the general hypersurface section [Formula: see text] is Du Val. Under that assumption, this paper describes the construction of a divisorial extraction from [Formula: see text] by Kustin–Miller unprojection. Terminal extractions from [Formula: see text] are proved not to exist if [Formula: see text] is of type [Formula: see text] or [Formula: see text] and are classified if [Formula: see text] is of type [Formula: see text] or [Formula: see text].

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Kearns, Steven M. "Extending regular expressions with context operators and parse extraction." Software: Practice and Experience 21, no. 8 (August 1991): 787–804. http://dx.doi.org/10.1002/spe.4380210803.

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Barbosa-Pereira, Letricia, Ainara Pocheville, Inmaculada Angulo, Perfecto Paseiro-Losada, and Jose M. Cruz. "Fractionation and Purification of Bioactive Compounds Obtained from a Brewery Waste Stream." BioMed Research International 2013 (2013): 1–11. http://dx.doi.org/10.1155/2013/408491.

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The brewery industry generates waste that could be used to yield a natural extract containing bioactive phenolic compounds. We compared two methods of purifying the crude extract—solid-phase extraction (SPE) and supercritical fluid extraction (SFE)—with the aim of improving the quality of the final extract for potential use as safe food additive, functional food ingredient, or nutraceutical. The predominant fractions yielded by SPE were the most active, and the fraction eluted with 30% (v/v) of methanol displayed the highest antioxidant activity (0.20 g L−1), similar to that of BHA. The most active fraction yielded by SFE (EC50of 0.23 g L−1) was obtained under the following conditions: temperature 40°C, pressure 140 bar, extraction time 30 minutes, ethanol (6%) as a modifier, and modifier flow 0.2 mL min−1. Finally, we found that SFE is the most suitable procedure for purifying the crude extracts and improves the organoleptic characteristics of the product: the final extract was odourless, did not contain solvent residues, and was not strongly coloured. Therefore, natural extracts obtained from the residual stream and purified by SFE can be used as natural antioxidants with potential applications in the food, cosmetic, and pharmaceutical industries.

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Ren, Xiao Feng, and Wen Jing Zhu. "Optimal Conditions for Extraction of Oil from Fenugreek (Trigonella foenum - graecum L.) by Supercritical CO₂ Fluids (SFE-CO₂)." Advanced Materials Research 236-238 (May 2011): 2980–83. http://dx.doi.org/10.4028/www.scientific.net/amr.236-238.2980.

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The optimal conditions for extracting of fenugreek oil from material with supercritical CO2 fluids：extraction temperature 40°C,extraction pressure 25MPa，separation temperature 60°C, separation pressure one atmosphere pressure. Adding 50%(V/W) absolute alcohol as modifier, the highest extraction ratio is 8.95mg/g dry fenugreek seeds.

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Deufemia, Vincenzo, Massimiliano Giordano, Giuseppe Polese, and Genoveffa Tortora. "A visual language-based system for extraction-transformation-loading development." Software: Practice and Experience 44, no. 12 (May 20, 2013): 1417–40. http://dx.doi.org/10.1002/spe.2201.

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K. P., Jevitha, Swaminathan Jayaraman, Bharat Jayaraman, and Sethumadhavan M. "Finite‐state model extraction and visualization from Java program execution." Software: Practice and Experience 51, no. 2 (October 11, 2020): 409–37. http://dx.doi.org/10.1002/spe.2910.

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Dimić, Ivana, Nemanja Teslić, Predrag Putnik, Danijela Bursać Kovačević, Zoran Zeković, Branislav Šojić, Živan Mrkonjić, Dušica Čolović, Domenico Montesano, and Branimir Pavlić. "Innovative and Conventional Valorizations of Grape Seeds from Winery By-Products as Sustainable Source of Lipophilic Antioxidants." Antioxidants 9, no. 7 (July 1, 2020): 568. http://dx.doi.org/10.3390/antiox9070568.

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The aim of this study was to valorize the oil recovery from red and white grape seeds (Vitis vinifera L.) that remains as by-product after the winemaking process. Oils were extracted by modern techniques, ultrasound assisted (UAE), microwave assisted (MAE) and supercritical fluid extraction (SFE), and compared to the Soxhlet extraction (SE). Firstly, SFE was optimized at different operating conditions: pressure (250–350 bar), temperature (40–60 °C), CO2 flow rate (0.2, 0.3 and 0.4 kg h−1), and particle size (315–800 µm and >800 µm). The highest extraction yields were achieved by SFE at the optimal conditions: 350 bar, 60 °C, 0.4 kg h−1. Afterwards, SFE was compared to SE, UAE and MAE with respect to oil extraction yields, and analyzed for fatty acid composition and antioxidant capacity. Considering the general classification of fatty acids, it was found that samples had high content of polyunsaturated fatty acids, regardless of extraction technology. Tocopherol content was significantly influenced by all extraction methods, whereas UAE and MAE resulted in extracts richer with lipophilic antioxidants. In conclusion, modern extractions that are suited for industrial applications had better performance as compared to SE, as judging by the oil yield and quality.

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Hasanah, Aliya Nur, Dang Soni, Rimadani Pratiwi, Driyanti Rahayu, Sandra Megantara, and Mutakin. "Synthesis of Diazepam-Imprinted Polymers with Two Functional Monomers in Chloroform Using a Bulk Polymerization Method." Journal of Chemistry 2020 (February 18, 2020): 1–8. http://dx.doi.org/10.1155/2020/7282415.

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Diazepam is a benzodiazepine that has the potency to be misused because it is effective, easily obtained, and inexpensive. The misuse of diazepam is to replace illegal drugs and be a sedative. Separation of diazepam is needed to detect possible drug abuse and to monitor drug levels in blood to ensure the effectiveness of the drug. This study was conducted to obtain a molecularly imprinted solid-phase extraction (MI-SPE) sorbent to separate diazepam from serum samples. This work started at the synthesis stage with the bulk polymerization method, using methyl methacrylate and acrylamide as functional monomers, diazepam as a template, and ethylene glycol dimethacrylate as a crosslinker. The polymer obtained was identified by its adsorption capacity and packaged into a solid-phase extraction (SPE) cartridge, and the extraction conditions were optimized. The optimization results were then used to extract diazepam from the serum sample. The test results showed that the adsorption ability of the molecularly imprinted polymer (MIP) with the functional monomer, methyl methacrylate, was 63.98 ± 0.1%, which is higher than that of the acrylamide MIP monomer, with a value of 43.27 ± 0.1%. The MIP sorbent of methyl methacrylate was applied to the SPE with 200 mg of polymer in a 3 mL cartridge. Diazepam added to serum samples were then passed through the MIP-SPE producing a percent recovery value of 95.31 ± 1.1% for MIP and 60.83 ± 0.3% for nonimprinted polymer (NIP). The results showed that the MI-SPE sorbent made from the monomer methyl methacrylate gave higher extraction recovery results than acrylamide, and it could be used for extracting diazepam from serum samples with or without other substances.

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Liu, Yi, Xinxin Luo, Min Wang, Zhining Xia, and Yike Huang. "Microorganisms as Bio-SPE Materials for Extraction of Pharmaceutical Drugs: Mechanism of Extraction." Analytical Chemistry 93, no. 21 (May 18, 2021): 7665–72. http://dx.doi.org/10.1021/acs.analchem.1c00521.

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Tuzimski, Tomasz, and Szymon Szubartowski. "Application of d-SPE before SPE and HPLC-FLD to Analyze Bisphenols in Human Breast Milk Samples." Molecules 26, no. 16 (August 14, 2021): 4930. http://dx.doi.org/10.3390/molecules26164930.

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In this study, we propose a simple, cost-effective, and sensitive high-performance liquid chromatography with fluorescence detection (HPLC-FLD) for the simultaneous determination of seven bisphenols (bisphenol F (BPF), bisphenol E (BPE), bisphenol B (BPB), BADGE (bisphenol A diglycidyl ether), BADGE∙2H2O, BADGE∙H2O, BADGE∙2HCl) in human breast milk samples. The dispersive solid phase extraction (d-SPE) coupled with solid phase extraction (SPE) procedure performed well for the majority of the analytes with recoveries in the range 57–88% and relative standard deviations (RSD%) of less than 9.4%. During the d-SPE stage, no significant matrix effect was observed thanks to the application of different pairs of salts such as zirconium-dioxide-based sorbents (Z-Sep or Z-Sep +) and primary secondary amine (PSA) or QuEChERS Enhanced Matrix Removal-Lipid (EMR-Lipid) and PSA. The method limits of quantification (mLOQs) for all investigated analytes were set at satisfactory low values in the range 171.89–235.11 ng mL−1. Analyte concentrations were determined as the average value from human breast milk matrix samples. The results show that the d-SPE/SPE procedure, especially with the application of EMR-Lipid and PSA, could be used for further bisphenol analyses in human breast milk samples.

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Zhang, Wei, and Dennis P. Curran. "Synthetic applications of fluorous solid-phase extraction (F-SPE)." Tetrahedron 62, no. 51 (December 2006): 11837–65. http://dx.doi.org/10.1016/j.tet.2006.08.051.

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38

Fang, Lianying, Xiangxing Wang, Limin Guo, and Qiang Liu. "Antioxidant, Anti-microbial Properties and Chemical Composition of Cumin Essential Oils Extracted by Three Methods." Open Chemistry 16, no. 1 (April 10, 2018): 291–97. http://dx.doi.org/10.1515/chem-2018-0034.

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AbstractThe purpose of this study is to evaluate the chemical composition, antioxidant and anti-bacterial activity of cumin essential oils (CEOs) extracted by different techniques, including supercritical carbon dioxide extraction (SCE), subcritical butane extraction (SBE) and traditional solvent extraction (SE). Our results indicated that CEOs are a valuable source of bioactive compounds, including cumin aldehyde, γ-terpinene and β-pinene. The most abundant components found in CEOs obtained by SCE and SBE were similar, while the abundant components in SE, β-Cumic aldehyde (19.31%) and α-phellandrene (9.49%), were distinctive. CEOs obtained by SCE exhibited higher antioxidant activity, followed by those extracted by SE and SBE. Moreover, the anti-microbial properties of CEOs obtained by SCE and SBE were higher than that of CEOs collected by SE. In conclusion, CEOs exhibit strong antioxidant and anti-microbial properties, which suggests a potential role of CEOs in preventing diseases associated with aging and oxidative stress, and our results highlight the potential usage of CEOs in the food industry.

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Jain, Rahul, Sanjeev Kumar Aggarwal, Pankaj Jalote, and Shiladitya Biswas. "An interactive method for extracting grammar from programs." Software: Practice and Experience 34, no. 5 (April 25, 2004): 433–47. http://dx.doi.org/10.1002/spe.568.

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40

NEARY, A. J., E. MISTRY, and L. VANDERSTAR. "SULPHATE RELATIONSHIPS IN SOME CENTRAL ONTARIO FOREST SOILS." Canadian Journal of Soil Science 67, no. 2 (May 1, 1987): 341–52. http://dx.doi.org/10.4141/cjss87-030.

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The [Formula: see text] status of sandy, podzolic soils from central Ontario was examined. Water-soluble [Formula: see text] was positively correlated with soil organic C concentrations but not with Fe and Al oxides (citrate-dithionite-bicarbonate minus pyrophosphate extractable Fe and Al). For adsorbed [Formula: see text] the reverse was true. Surface horizons were high in soluble [Formula: see text] and low in adsorbed [Formula: see text] whereas B horizons containing high levels of Fe and Al oxides contained large amounts of adsorbed [Formula: see text] and little soluble [Formula: see text]. Successive distilled water extractions of some samples indicated the removal of almost all soluble [Formula: see text] from surface horizons in one or two extractions. Sulphate, however, remained present in the B horizons after five extractions. The amount of soluble [Formula: see text] extracted was dependent on horizon type and amount of water used for extraction. This makes evident the importance of moisture status, residence time and hydrologic pathways in determining [Formula: see text] release from the soil, and demonstrates the need for in situ studies. Plastic Lake B horizons adsorbed added [Formula: see text] in the laboratory but it was not determined whether this is occurring in the field. Key words: Soluble [Formula: see text], adsorbed [Formula: see text], sulphate, iron oxide, aluminum oxide, podzol

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Hopper, Marvin L., Jerry W. King, James H. Johnson, Alberta A. Serino, and Robert J. Butler. "Multivessel Supercritical Fluid Extraction of Food Items in Total Diet Study." Journal of AOAC INTERNATIONAL 78, no. 4 (July 1, 1995): 1072–78. http://dx.doi.org/10.1093/jaoac/78.4.1072.

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Abstract An off-line, large capacity, multivessel supercritical fluid extractor (SFE) was designed and constructed for extraction of large samples. The extractor can simultaneously process 1–6 samples (15–25 g) by using supercritical carbon dioxide (SC–CO2), which is relatively nontoxic and nonflammable, as the solvent extraction medium. Lipid recoveries for the SFE system were comparable to those obtained by blending or Soxhlet extraction procedures. Extractions at 10 000 psi, 80°C, expanded gaseous CO2 flow rates of 4–5 L/min (35°C), and 1–3 h extraction times gave reproducible lipid recoveries for pork sausage (relative standard deviation [RSD], 1.32%), corn chips (RSD, 0.46%), Cheddar cheese (RSD, 1.14%), and peanut butter (RSD, 0.44%). In addition, this SFE system gave reproducible recoveries (>93%) for butter fortified with c/s-chlordane and malathion at the 100 ppm and 0.1 ppm levels. Six portions each of Cheddar cheese, saltine crackers, sandwich cookies, and ground hamburger also were simultaneously extracted with SC-CO2 and analyzed for incurred pesticide residues. Results obtained with this SFE system were reproducible and comparable with results from organic-solvent extraction procedures currently used in the Total Diet Study; therefore, use and disposal of large quantities of organic solvents can be eliminated.

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42

Althoff, Marc André, Andreas Bertsch, and Manfred Metzulat. "Automation of µ-SPE (Smart-SPE) and Liquid-Liquid Extraction Applied for the Analysis of Chemical Warfare Agents." Separations 6, no. 4 (October 9, 2019): 49. http://dx.doi.org/10.3390/separations6040049.

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Existing autosamplers are frequently applied only for subjecting the samples to the instruments for injection. In our study, we have set up a TriPlusRSH autosampler mounted on a GC-FID-MS/MS system using the new Method Composer and Script Editor software to automatize all necessary sample preparation steps and subsequent injection of samples in the field of chemical disarmament. Those include but are not limited to: liquid-liquid extraction, drying steps, solvent exchange, and µ-SPE. Tedious and error prone off-line steps are eliminated. In particular, when investigating highly toxic substances like chemical warfare agents or anticancer drugs, automation can help to minimize health risks for lab personnel. The setup engaged features brand new prototype equipment, e.g., a centrifuge to assist in phase separation for liquid-liquid extraction. Efficiency and accuracy of the automated methods were carefully evaluated and proven to outperform the respective manual steps after optimization, e.g., the processing time is up to 60% faster and recovery rates are doubled. The developed workflows can easily be adapted to other sample preparation protocols, e.g., determination of octanol/water partition coefficients, and be used amongst different instruments and chromatography data handling systems.

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Tampu, Raluca, Catalin Tampu, and Claire Elfakir. "Optimization of SPE method for the extraction of 12 neurotransmitters from sheep brain." Ovidius University Annals of Chemistry 31, no. 2 (January 1, 2020): 110–21. http://dx.doi.org/10.2478/auoc-2020-0020.

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Abstract The present paper presents our attempts concerning the development of an extraction method for catecholamines. In order to achieve the extraction of all the selected solutes using a single SPE cartridge, several types of support were tested, among them: cation exchange supports, hydrophilic-lipophilic supports, C18 supports and PGC supports. As unfortunately none of the supports tested offered us the possibility of carrying out the extraction of 12 catecholamines from our standard mixture, we chose to use a coupling of two different cartridges: Oasis HLB and PGC which together ensure the extraction of all the compounds of the mixture with good extraction yields and with simple protocols. The selected cartridges were successfully tested for the extraction of a sample spiked from sheep brain with the 12 catecholamines in our mixture. The SPE method that we have developed allows the purification of the samples (a significant part of the components of the matrix is eliminated during this step) and also a preconcentration of the samples.

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Tang, Peter H., James S. Ho, and James W. Eichelberger. "Determination of Organic Pollutants in Reagent Water by Liquid-Solid Extraction Followed by Supercritical Fluid Elution." Journal of AOAC INTERNATIONAL 76, no. 1 (January 1, 1993): 72–82. http://dx.doi.org/10.1093/jaoac/76.1.72.

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Abstract A selected group of polynuclear aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides, and phthalate esters in reagent water containing no particulate matter were separated and identified by liquid-solid extraction and supercritical fluid extraction (SFE). The water sample is first passed through a cartridge or disk containing a solid matrix coated with a chemically bonded C18 organic phase capable of extracting those organic compounds. The cartridge or the disk is then eluted with supercritical carbon dioxide to remove the compounds from the sorbent. Finally, the extract is injected into a capillary column gas chromatographic/quadruple mass spectrometric system. The precisions, percent recoveries of analytes using solvent elution, and percent recoveries using SFE are compared. The total analysis time is greatly reduced by using disk extraction and SFE in place of cartridge extraction and liquid-solvent elution. In addition, the waste solvent generated was minimized by using SFE.

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Tartaglia, Angela, Abuzar Kabir, Songul Ulusoy, Halil Ibrahim Ulusoy, Giuseppe Maria Merone, Fabio Savini, Cristian D’Ovidio, et al. "Novel MIPs-Parabens based SPE Stationary Phases Characterization and Application." Molecules 24, no. 18 (September 13, 2019): 3334. http://dx.doi.org/10.3390/molecules24183334.

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In this work, the synthesis, characterization, and application of novel parabens imprinted polymers as highly selective solid-phase extraction (SPE) sorbents have been reported. The imprinted polymers were created using sol–gel molecular imprinting process. All the seven parabens were considered herein in order to check the phase selectivity. By means of a validated HPLC-photodiode array detector (PDA) method all seven parabens were resolved in a single chromatographic run of 25 min. These SPE sorbents, in-house packed in SPE empty cartridges, were first characterized in terms of extraction capability, breakthrough volume, retention volume, hold-up volume, number of theoretical plates, and retention factor. Finally, the device was applied to a real urine sample to check the method feasibility on a very complex matrix. The new paraben imprinted SPE sorbents, not yet present in the literature, potentially encourage the development of novel molecularly imprinted polymers (MIPs) to enhance the extraction efficiency, and consequently the overall analytical performances, when the trace quantification is required.

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Sips, Luc, Emmanuel Njumbe Ediage, Benno Ingelse, Tom Verhaeghe, and Lieve Dillen. "LC–MS quantification of oligonucleotides in biological matrices with SPE or hybridization extraction." Bioanalysis 11, no. 21 (November 2019): 1941–54. http://dx.doi.org/10.4155/bio-2019-0117.

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Aim: Quantitative LC–MS analysis of oligonucleotides (OGNs) in biological matrices is needed to support candidate selection of new therapeutic OGNs. Methodology & results: A set of 20 single stranded antisense oligonucleotides (ASO) and five siRNAs were extracted from plasma and tissue homogenates. Anion Exchange (AEX) SPE was selected as generic extraction approach, resulting in recoveries from plasma >70%. Extraction from tissue homogenates showed often more variation and lower recoveries. A proof of concept of a novel tailored hybridization extraction is demonstrated for two 16-mer reference OGNs. Conclusion: Two methods for extraction of OGNs were investigated and applied for quantitative analysis. The AEX-SPE is considered a more generic approach preferred when multiple compounds are evaluated. Hybridization extraction has great potential but critical reagents per analyte are needed.

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47

Cikoš, Ana-Marija, Stela Jokić, Drago Šubarić, and Igor Jerković. "Overview on the Application of Modern Methods for the Extraction of Bioactive Compounds from Marine Macroalgae." Marine Drugs 16, no. 10 (September 23, 2018): 348. http://dx.doi.org/10.3390/md16100348.

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Marine macroalgae represent a rich source of bioactive compounds that can be implemented in various food, cosmetic, and pharmaceutical products for health improvement. It has been proven that these bioactive compounds, such as polyphenols, polysaccharides, carotenoids, and ω-3 fatty acids possess bioactivity. For the extraction of these compounds, modern methods (Supercritical Fluid Extraction (SFE), Subcritical Water Extraction (SWE), Ultrasound-Assisted Extraction (UAE), and Microwave-Assisted Extraction (MAE)) have been used due to their advantages over the conventional methods. The process parameters of each method must be optimized for obtaining the extracts with the targeted bioactive compounds. In distinction from the existing reviews, the present review provides novelty with respect to: (a) presenting systematically the selected process parameters of SFE (temperature, time, pressure, use of co-solvents), SWE (temperature, time, pressure, solid-solvent ratio), UAE (temperature, time, frequency, power, solid-solvent ratio), and MAE (temperature, time, frequency, power, solvent type) applied for the extractions of marine macroalgae; (b) reporting the major groups or individual compounds extracted with their biological activities (if determined); and, (c) updating available references.

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Guan, Xiao, Depeng Ge, Sen Li, Kai Huang, Jing Liu, and Fan Li. "Chemical Composition and Antimicrobial Activities of Artemisia argyi Lévl. et Vant Essential Oils Extracted by Simultaneous Distillation-Extraction, Subcritical Extraction and Hydrodistillation." Molecules 24, no. 3 (January 29, 2019): 483. http://dx.doi.org/10.3390/molecules24030483.

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Artemisia argyi Lévl. et Vant essential oil could be used as a good antimicrobial flavouring agent and applied in the food industry. In this study, three methods, including simultaneous distillation-extraction (SDE), subcritical extraction and hydrodistillation, were applied to extract A. argyi essential oil. Compared with subcritical extraction (1%) and hydrodistillation (0.5%), SDE gave a higher yield (1.2%). Components of the essential oils were analysed with gas chromatography-mass spectrometry (GC-MS), and the most abundant ingredients were caryophyllene oxide, neointermedeol, borneol, α-thujone and β-caryophyllene. These five components accounted for 82.93%, 40.90% and 40.33% for SDE, subcritical extraction, and hydrodistillation, respectively. Based on agar disc diffusion and minimum inhibitory concentration (MIC) assays, SDE oil showed a significant inhibitory effect towards Listeria monocytogenes, Escherichia coli, Proteus vulgaris, Salmonella enteritidis and Aspergillus niger. Furthermore, electron microscope observations (SEM) confirmed that SDE oil could obviously deform cell morphology and destroy the structure of cell walls. Performances showed that SDE was a promising process for extracting A. argyi essential oil with both high yield and antimicrobial activity.

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Mutavdžić, Dragana, Alka J. M. Horvat, Sandra Babić, and Marija Kaštelan-Macan. "SPE - Microwave-assisted extraction coupled system for the extraction of pesticides from water samples." Journal of Separation Science 28, no. 13 (August 2005): 1485–92. http://dx.doi.org/10.1002/jssc.200400061.

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Ivanov, Dusica, Radmilo Colovic, Bojana Beljkas, Jovanka Levic, and Slavica Sredanovic. "Optimization of co-solvent addition in supercritical fluid extraction of fat with carbon dioxide." Acta Periodica Technologica, no. 42 (2011): 45–53. http://dx.doi.org/10.2298/apt1142045i.

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This investigation is concerned with supercritical fluid extraction (SFE) using CO2, as an analytical technique for total fat extraction from food and feed samples. Its most significant advantages are safety, cleanness, and shorter extraction time. The main limitation of this technique includes the difficulty of extracting polar lipids due to the non-polar character of the solvent (CO2) used for the extraction. The influence of ethanol as a co-solvent on the SFE of mash pig feed was investigated in this paper. Total fat content was determined by SFE and Soxhlet method for ten commercially available mesh pig feeds. Yields of the fat extracted by both methods were plotted one against the other and compared. Statistically significant difference (p ? 0.05) has been found only between the total fat obtained by the Soxhlet extraction and SFE by pure CO2. Based on the mathematical model, maximum yield of the extracted fat is achieved at an ethanol addition of 0.67 ml/g of sample, when the other parameters are the same as recommended by the producer?s procedure.

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Journal articles on the topic 'Extractions SPE'

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