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The article offers information on formal and informal training opportunities that may be available to educate all chemists in the fundamentals of these necessary laboratory skills. It mentions that analytical chemistry textbooks provide an overview, at best, of the practice of extraction; and also mentions about Liquid–liquid extraction (LLE), including proper use of separatory funnels, is found in organic chemistry laboratory manuals.

The article presents a study on the proposed intentional incorporation of an air bubble into a solvent droplet for fully automated bubble-in-drop microextraction-gas chromatography-mass spectrometric (BID-GC-MS) analysis of selected organochlorine pesticides as model analytes. The use of a commercial autosampler coupled to a GC-MS system without human intervention is explored. It found out a less error than that associated with manual injection and significant reduction in labor intensiveness.

The article presents information related to headspace sampling, which is the vapor phase, typically, above a liquid or solid sample and its quantitative nature. It refers to the advantages of sampling this gaseous, or headspace, phase for injection into gas chromatography (GC). It also presents a depiction of a static equilibrium headspace system.

The article offers information on the origin of the theoretical plate concept which can be used to develop and formulate chromatographic theory. Topics discussed include the application of theoretical plates to fractional distillation and countercurrent extractions, the applicability of the process, and the assessment of distillation efficacy.

The article presents the introduction of sample preparation technologies from different companies. Topics mention including the Energized Dispersive Guided Extraction (EDGE) system from CEM, Pulsed Evaporative Concentration Extraction (PECE) system from Entech Instruments and sorbent-based and solid-phase sorbent products.

A science experiment for the quantification of 12 polybrominated diphenyl ethers (PBDEs) in dried blood spots is presented using analysis by gas chromatography- tandem mass spectrometry (GC-MS/MS) and a straightforward sample extraction method. It describes instrumentation and sample preparation for the experiment. It highlights the use of dried blood spot cards for toxicological studies.

The article focuses on the principles and applications of cloud-point extraction, (CPE) technique used for the isolation of organic compounds. It highlights several advantages for organic extractions offered by the CPE method. It describes other sample preparation techniques based on the formation of coacervates.

A simple method for extraction and concentration of trace organic compounds found in water for gas chromatography-mass spectrometry (GC–MS) analysis was developed. The method used 25- and 45-mL glass vials with 5-10 pm thick polymer coatings for extraction of analytes from 20- and 40-mL water samples, respectively. Analytes were subsequently transferred from the polymer coating into an organic solvent, which was reduced in volume to 200-400 pL for analysis. A 10-20 pL sample from the vial was transferred to a tiny coiled stainless steel wire filament using a microsyringe, or by dipping the coil into the sample. After air evaporation of the solvent, the coil was inserted into the heated injection port of a portable GC–MS system where the analytes were desorbed. Injection using the coiled wire filament eliminated sample discrimination of high boiling point compounds and minimized system contamination caused by sample matrix residues. The elution of low-volatility compounds was accomplished in less than 4 min. Analyses of organochlorine pesticides, polycyclic aromatic hydrocarbons, polychlorinated biphenyl congeners, pyrethroid insecticides, phthalate esters, and n-alkanes in water and wastewater samples were accomplished for low parts-per-billion concentrations in a total analysis time of less than 10 min. [ABSTRACT FROM AUTHOR]

A solid-phase microextraction (SPME) method was developed using a new overcoated polydimethylsiloxane-divinylbenzene (PDMS-DVB) fiber for immersion extraction of pesticide residues from spaghetti sauce. The overcoating offered protection to the SPME fiber, making it more resistant to physical and chemical damage. Also, it increased fiber selectivity for the smaller analyte molecules over macromolecules present in sample matrix. These attributes then allowed it to be used in immersion extraction of a very complex matrix—spaghetti sauce. Performance of the overcoated fiber was compared to that of a nonovercoated fiber of the same chemistry for method accuracy, precision, and durability. The SPME method developed using the overcoated fiber was then compared to extraction of the same pesticides in spaghetti sauce using a conventional QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for extraction and cleanup. SPME was comparable to the QuEChERs method for both accuracy and precision. However, its main advantage compared to QuEChERS was in sensitivity and method simplicity. [ABSTRACT FROM AUTHOR]

Adequate detection of trans-resveratrol in wine is complicated by two factors: relatively low levels and interferences from matrix components. Here, we present two useful approaches to overcoming these issues depending on the instrumentation available. For high performance liquid chromatography (HPLC) analyses with ultraviolet (UV) detection, matrix peaks can be removed by microextraction using a packed sorbent while simultaneously concentrating the trans-resveratrol peak by a factor of two. For liquid chromatography-mass spectrometry (LC-MS), the extracted ion chromatogram for the [M + H]+ analyte ion can be used to obtain specificity without prior extraction procedures. [ABSTRACT FROM AUTHOR]

Limestone has been extracted very successfully from the "Laybruch" deposit for more than 155 years for Schaefer Kalk GmbH & Co. KG at Hahnstätten. Over the coming years this is to be gradually replaced by the "Merschelbruch" deposit. Schaefer Kalk has installed a new crushing plant with downstream processing plant at the edge of the new deposit to ensure the customary high product quality. Initial planning started in 2003 during the authorization procedure to open up this deposit. Construction began in 2013 after the planning process was re-started in 2011. Trial operation began in early 2015. 180000 m3 earth were removed to develop the working area and conveyor belt routes and 9500 m3 concrete, 14501 reinforcing steel and 5001 structural steel were used to construct the requisite building. The planning jurisdiction for the entire project was handled by Schaefer Kalk so all the trades and machine suppliers could be coordinated centrally. This meant that it was also possible to secure the optimum design for all machines and plants and to design a basic version of the entire plant that could be extended modularly, with a material turnover of 350 t/d that can be increased to up to 500 t/h in the coming years by increasing the efficiency. From the individual machines and the sometimes unique closed control systems of the units that were supplied it was possible to generate an optimum higher-level control system and visual display. All the information needed for monitoring is supplied directly to the operator through the central process control system. [ABSTRACT FROM AUTHOR]

An interview with Alicia D. Stell, product manager at microwave-based laboratory systems provider CEM Corp., is presented. Topics discussed include the benefits of using an automated system produced by CEM called EDGE which combines pressurized fluid and dispersive solid-phase extractions, applications of EDGE for consumer products, and the extraction of fats from foods by EDGE.

The article discusses the development of a high throughput sample preparation method validated for several drug abuse and metabolites quantitation using polymeric SPE plate. It also discusses the hydrolysis of urine samples with E. Coli recombinant ß-glucuronidase and extraction with Panthera Deluxe SPE plate, including the hydrolysis and extraction recovery rate.

The article discusses the year-old sample preparation technique solid-phase microextraction (SPME) and related techniques like placing of sorbent coatings on magnetic particles, stir bars, etc. It also discusses the advancement in the SPME, including the increase of extraction-supportive sorbent surface area, fouling-resistant sorbent overcoating, and direct analysis accommodation by mass spectrometry.

The article discusses basic scientific principles related to Solid-Phase Extraction (SPE) to select the correct mode of extraction through right understanding of interaction and seperation of analytes with sorbent. Topics discussed include basic categories of SPE Mechanisms, some of the most common causes of low recovery in SPE and emerging technologies within the area.

The article evaluates the Milli-Q IQ 7000 water purification system equipment from EMD Millipore Corp., the Dursan bioinert coating equipment from SilcoTek Corp. and the Pressurized liquid extraction system machine from FMS Inc.

The article discusses the exploration on the possibilities of analytical procedure in sample preparation of extraction techniques. It offers information on the list of the uses of filtration microplates in pharmaceutical development including dye terminator removal, filtration of precipitated proteins and plasmid DNA binding. It also emphasizes the study of the effect of combustion ion chromatography on the use of halogens in polymers.

The article presents a study on the significant role of radical ion chemistry for mass spectrometry (MS) development and the bioanalysis application. It states the establishment of MS as an essential tool for qualitative and quantitative chemical analysis which involves its principle of analysis and steps for extracting. It also highlights the importance of bio-radicals in the implication of a wide variety of biochemical process.

Recent advances in sampling techniques in the pharmaceutical industry sparked significant interest in applying improvements to extraction methods for greater analyte detection and quantitation. In particular, the dried blood spot (DBS) sampling technique has numerous advantages compared to traditional methods such as liquid-liquid extraction, including the use of small sample volumes, less sample processing, and less exposure to toxic solvents (ether, methyl tertbutyl ether [MTBE], and dichloromethane). In this article, we discuss the adaptation of DBS technology to develop and validate a novel paper strip extraction method for the analysis of natural product metabolites in biological samples obtained from a human pharmacokinetic study of xanthohumol, a hop prenylflavonoid. [ABSTRACT FROM AUTHOR]

The article presents a case study which show the extraction methods for determining the composition of the fatty acid methyl esters (FAME). It discusses several methods including the supercritical fluid extraction, solid-phase extraction, and lipase hydrolysis. It mentions that the analytic selectivity occurs during steps of analytical method, but typically occurs during separation or detection steps rather than during sample preparation.

The article presents several preparation methods to remove the interferences and concentrate analytes of interest. These includes the electroextraction (EE), a sample enrichment technique that focus on changed analytes from large volume of aqueous phase. The electroenhanced solid-phase microextraction (SPME) is used in gas, liquid, and headspace analysis. It mentions the solid-phase extraction (SPE) method is used before chromatographic analysis and relies on principles of retention-elution.

The article discusses the new sorbent materials which have the potential to help in solving specific chromatography laboratory problems. It states the increased application of solid-phase microextraction (SPME), solid-phase extraction (SPE), and stir-bar sorbent extraction (SBSE) in diverse markets. In addition, it cites molecularly imprinted polymers (MIPs) as one of the selective phases used in SPE such as in areas where selective recognition is needed.

Pressurized fluid extraction (PFE) is an automated extraction technique that uses elevated temperature and pressure to increase the rate and efficiency of the extraction process. PFE reduces the amount of time and solvent required, while significantly improving laboratory throughput relative to traditional extraction techniques such as Soxhlet. This article discusses current advances in commercial PFE instrumentation and show how these systems can benefit scientists in analytical laboratories who wish to perform automated extraction. [ABSTRACT FROM AUTHOR]

Pressurized high temperature or superheated water is a green extraction solvent used in food, environmental, and traditional medicine studies for the extraction of non-polar and polar analytes including essential oils and spices, agrochemicals, pharmaceuticals, and petrochemicals. The technique can be used on both the analytical and preparative scale to give a clean, solvent-free product for chromatographic analysis. This article reviews the current status of superheated water extraction, discussing extraction methods, applications, and, briefly, problems encountered with this approach [ABSTRACT FROM AUTHOR]

The article discusses the tools that can be used for the development of computer-assisted methods for multistep elution profiles in ion chromatography (IC). A four-step elution profile is suggested for simulating the separation. It further concludes that isocratic data based rapid calculation of retention factors helps simulating any desired eluent profile and can optimize the separation manually without experimentation.

The article discusses uses of polymeric ionic liquids (PILs) and ionic liquids (ILs) for process of dispersive liquid-liquid microextraction (DLLME) and solid-phase microextraction (SPME). It informs that ILs are described as organic salts which consist of melting points at a level of 100 degree Celsius. It mentions that PILs have been used previously in several methods including single-drop microextraction (SDME), solid-phase microextraction (SPME) and liquid-phase microextraction (LPME).

The article discusses the extraction and concentration of polymer additives and side products present in synthetic polymers used in chromatographic analysis. It mentions that polymer may become contaminated during or after polymerization, processing, or fabrication. It recommends methods used for reducing particle size of polymeric materials including blending, chopping and sieving. It mentions that liquid-solid extraction method is most popular method for concentration of synthetic polymers.

An analytical method has been developed on the Agilent 7000 Series triple quadrupole gas chromatograph/mass spectrometer (GC/MS) for the analysis of polyaromatic hydrocarbons (PAHs) and polybrominated diphenyl ethers (PBDEs) in wastewater. With a single extraction and no cleanup, this method meets the detection limit requirements of the United Kingdom Chemical Investigations Programme. [ABSTRACT FROM AUTHOR]

The article focuses on phospholipids and their effect on bionalaytical analysis. When these samples are subjected to liquid chromatography coupled with tandem mass spectrometry (LC-MS-MS) ion suppression and shortened column life happen due to presence of phospholipids. Use of phospholipids removal device in sample preparation techniques such as solid-phase extraction (SPE) and protein precipitation though reduce phospholipids content but have no effect on protein content.

The article presents information regarding the extraction of Uranium from the sea water. It ids mentioned that the oceans contain staggering quantity uranium and heavy element. According to Benjamin P. Hay, a scientist, Earth's oceans contain more than 4 billion metric tons of dissolved uranium which is 1,000 times greater than all known terrestrial sources. It informs that the main challenge in extracting Uranium from the ocean in a large-scale can cause negative effects on marine conditions and the lives of animals associated with it.

The article discusses the practical aspects of hollow fiber liquid-phase microextraction in the three-phase mode (HF3LPME). It notes the use of HF3LPME for extracting basic or acidic analytes from aqueous samples, as well as its advantages including low solvent consumption, and excellent sample cleanup. Moreover, it explores the significance of supported liquid membrane (SLM), as well as correct pH of sample and acceptor solutions on the extraction procedure.

The article highlights the benefits of membrane and solid sorbent combination into a single format. It mentions that solid sorbent and membrane combination into a single format has the potential for synergy creation that allows target compound selective extraction from complex samples. It offers that there is the increase in sample throughput compared to when cleanup and extraction are two different steps.

In this study, a solid-phase extraction (SPE) procedure is described that isolates both psilocybin and psilocin from urine samples. Extraction was performed using a mixed-mode SPE column. Samples of urine were diluted with aqueous phosphate buffer (pH 6). After the sample was applied to the SPE column, the sorbent was washed with deionized water and methanol. The analytes were eluted from the SPE column with 3 ml of ethyl acetate containing 2% ammonium hydroxide followed by 3 ml of methanol containing 4% ammonium hydroxide. The individual eluates were collected, evaporated to dryness, and dissolved in mobile phase (50 p1) before being combined for analysis by liquid chromatography-tandem mass spectrometry (LC-MS-MS). Chromatography was performed in gradient mode using a (18 column and a mobile phase consisting of acetonitrile and 0.1% aqueous formic acid. The total run time for each analysis was <5 mm. The limits of quantitation or detection for this method were determined to be 10 ng/ml and 5 ng/ml for both psilocybin and psilocin, respectively. The method was found to be linear from 10 ng/ml to 1000 ng/ml (r²> 0.995) for both compounds (psilocybin and psilocin). Recoveries of the psilocybin and psilocin were found to be greater than 85%. [ABSTRACT FROM AUTHOR]

The article discusses the aspects of octadecyl bonded silica gel (C18), commonly used phases in solid-phases extraction (SPE) applications. It notes that all C18 is not equal in terms of variations which include particle size, poor size and surface chemistry. The authors explore these differences and their influence on extraction performance.

A new concept for the extraction of solid samples has been developed. The popular pressurized liquid extraction (PLE) technique has been modified so that the extraction cell can be divided, which greatly increases the flexibility and versatility of this technique. The system uses simple adapters to couple commercially available extraction cells, which can be loaded with either sample or adsorbents. These segmented extraction cells make it possible to selectively retain analytes or matrix to achieve simultaneous extraction and cleanup or fractionation. The ultimate aim is to perform simultaneous extraction and cleanup and obtain a purified extract that is ready for instrumental analysis, all in line with current trends in analytical chemistry to automate and streamline the analytical procedures to reduce the analysis costs, solvent consumption, and manual labor, and increase the quality of analysis. Selected modes of operations are presented and a few recent environmental applications of modular PLE are reviewed. [ABSTRACT FROM AUTHOR]

This article describes a rapid, space-saving, and harmless method of sample preparation followed by reversed-phase high performance liquid chromatography with diode-array detection to quantify melamine in milk. The milk extract including melamine was purified using a centrifugal ultrafiltration device. The total analytical time was <20 mm for each sample and no organic solvents were used at any stage of the analysis. [ABSTRACT FROM AUTHOR]

The article presents a comparative study on the efficiency of using supercritical fluid extraction (SFE) and pressurized solvent extraction (PSE) in the recovery of gamma-Tocopherols in walnut oil in the U.S. The two techniques have been compared in terms of the total processing time, total hydrocarbon-based solvents required, and the total gamma- tocopherols extracted. The study intends to determine the efficiency of SFE and PSE in the removal of gamma-tocopherol from walnuts.

New requirements for dietary supplements to be manufactured under cGMP regulations have created a need for methods to detect pesticides in these complex, largely botanical products (for example, vitamins, herbal and botanical pills) Because dietary supplements contain natural products where pesticides have been employed, methods for pesticide analysis must be evaluated, including sample extraction and cleanup as well as instrumental techniques such as gas chromatography (GC). The QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample preparation approach offers a rapid way to prepare samples for analysis, but dietary supplement extracts can be so complex as to make trace-level pesticide determinations problematic. In this work, we evaluate a method involving QuEChERS extraction and dispersive solid- phase extraction (dSPE) cleanup, cartridge SPE (cSPE) cleanup, and GC with time-of-flight mass spectrometry (GC-TOF-MS) to detect pesticide residues in dandelion root powder obtained from a dietary supplement vendor. [ABSTRACT FROM AUTHOR]

The article evaluates several products related to chromatographic analysis including Ultimate 3000 high performance liquid chromatography (HPLC) system from Dionex Corp., ISOLUTE QuECHeRS extraction and clean-up produts from Biotage Inc., and microplates for chromatography from MicroLiter Analytical Supplies Inc.

The potential of selected ion flow tube mass spectrometry (SIFT-MS) to differentiate malted barley cultivars on the basis of their headspace profiles has been investigated. From a broad range of volatiles, marker aldehydes were selected because they are associated with malt quality and beer flavor stability. The authors used dynamic headspace SIFT-MS to identify the target volatiles in the different malt headspaces. The technique exhibited an increase in specificity and speed compared with the headspace solid-phase microextraction (SPME) gas chromatography- MS method currently used. The unique feature of SIFT-MS to analyze sample headspaces rapidly and directly without the need for sample preparation, derivatization, or chromatographic preseparation is demonstrated. [ABSTRACT FROM AUTHOR]

A new concept for the extraction of solid samples has been developed. The popular pressurized liquid extraction (PLE) technique has been modified so that the extraction cell can be divided, which greatly increases the flexibility and versatility of this technique. The system uses simple adapters to couple commercially available extraction cells, which can be loaded with either sample or adsorbents. These segmented extraction cells make it possible to selectively retain analytes or matrix to achieve simultaneous extraction and cleanup or fractionation. The ultimate aim is to perform simultaneous extraction and cleanup and obtain a purified extract that is ready for instrumental analysis, all in line with current trends in analytical chemistry to automate and streamline the analytical procedures to reduce the analysis costs, solvent consumption, and manual labor, and increase the quality of analysis. Selected modes of operations are presented and a few recent environmental applications of modular PIE are reviewed. [ABSTRACT FROM AUTHOR]

The article provides information on electromembrane extraction, a new sample preparation technique. It explores the capacity of electroextraction with hollow-fiber liquid-phase microextraction to achieve a rapid preparation method for charged substances isolation. A chart is also presented depicting the application examples of several biological matrices combinations.

The article discusses the use of speciated isotope dilution mass spectrometry (IDMS) in order to speciate mercury in crude oil. It mentions that the extraction of total mercury, soluble mercury fraction, and non-soluble mercury fraction was achieved using the U.S. Environmental Protection Agency Method 3052, 3200 and 6800 respectively. It states that the nonextractable elements were grouped, and the development for a new collective isotopic spiking protocol was required.

The article offers information on various advancement in sample preparation technologies. It mentions the pressure cycling technology (PCT) process developed by Pressure BioSciences Inc. to extract biomolecules from tissues using the Barocycler®. It reveals the Synchronous Coefficient of Drag Alteration (SCODA) devised by Boreal Genomics Inc. to move, select, and separate nucleic acids from contaminants. It also cites the glass probe for flavor extraction manufactured by Symrise Inc.

Membrane techniques have been used in many analytical applications and processes such as the selective removal and concentration of cations in solution, selective separation of gases and organic compounds in complex mixtures, and also in the recovery of acid and basic compounds. Authors from South Africa review the application of membranes in the extraction, preconcentration, and separation of various contaminants in foods. Emphasis is on the suitability of various membrane-based extraction techniques to selectively extract target compounds from complex food matrices, an area of growing importance. [ABSTRACT FROM AUTHOR]

The article discusses the use of fourier-transform infrared (FT-IR) and horizontal attenuated total reflectane (HATR) techniques in obtaining the FT-IR spectra of yellow foxtail seed, giant foxtail seed and green foxtail seed. It states that the HATF-FT-IR method is an effective way to classify plants since the reproductive organ of the seed contains more stable characters than the vegetative organ.

The article compares the abilities of silica-based solid-phase extraction (SPE) and polymer-based SPE. The author explains that silica-based sorbents can be applied to any SPE problem, but they have a limited pH range and have the presence of residual silanol groups. Polymeric sorbents, on the other hand, promise a wide pH range and their ability to tolerate solvents and buffers that would harm or destryo a silica-based sorbent.

The article focuses on the use of immunosorbents (ISs) for liquid sample preparation. It is stated that ISs are used in a manner similar to solid-phase extraction (SPE) cartridges, one of the most popular approaches to pretreat liquid samples. ISs can be packed into high performance liquid chromatography (HPLC) column hardware. Further, the ISs accounts the combination of high affinity and high selectivity of the antigen-antibody interaction.

The article discusses the emerging sample preparation technique becoming popular in the area of multiresidue pesticide analysis in food and agricultural products. The sample preparation technique called QuEChERS, uses simple glassware, a minimal quantity of organic solvent, and various salt/buffer additives to partition analytes into an organic phase for cleanup by dispersive-solid-phase extraction. It is cheaper than other preparation technique and provides good recoveries.

The article provides information concerning the consumption of reagent for copper production in the U.S. Reagent consumption is an important consideration in any commercial copper solvent extraction circuit. Reagent consumption is divided into two categories, including the mechanical loss of the organic phase, and the loss of extractant by hydrolytic and other forms of degradation. The article also examines the main factors that influence the consumption of reagents and considers the validity of comparing the relative performance of different plant using the widely used Reagent Usage metric.