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The flavours of malt whisky result from a complex blend of long chain esters and alcohols, derived from the distillation products and the composition of the wooden barrels in which the finished product is aged. As shown below, the new VF-WAXms column from Varian, Inc. is ideal for analysing whisky, especially when trace analysis is needed. The column's ultra-low bleed increases sensitivity, extends column life and improves accuracy, even at higher temperatures. In addition, VF-WAXms columns are suitable for use with MS detectors, as the ultra low bleed eliminates interferences and permits more sensitive detection.

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Molecularly imprinted polymers (MIPs) are synthetic polymeric materials that mimic immunosorbents. They are widely used as sorbents for solid-phase extraction (SPE). The most common way to synthesize them is bulk polymerization because of its simplicity and versatility. This produces a hard monolith that has to be ground and sieved to obtain particles in the desired size range. However, the partial loss of the materials as fine dusts; the irregular shape of the particles produced and their wide size distribution, have led to a search for different polymerization methods to offset the drawbacks of the bulk polymerization process.

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Combining an ultra fast LC system (e.g., Agilent 1200RRLC, Waters UPLC) with an accurate mass TOF mass spectrometer creates a powerful system for information-rich high-throughput analyses. However, for de novo formula generation and confirmation the residual mass accuracy tolerance of 3–5 ppm can still leave significant ambiguity in the proposed formula. Consequently, skilled manual inspection or further measurements deploying additional analytical techniques (NMR or MS–MS) are frequently required to arrive at a confident formula assignment.

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Pavel Jandera spoke to Frantisek Foret about building his own liquid chromatograph, the birth of “modern” high performance liquid chromatography (HPLC), the importance of exploring (and understanding) earlier research papers, current trends in contemporary chromatography, and his inspiring advice for aspiring chromatographers.

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Mass spectrometers are effective for identifying and quantifying unknown molecules, such as disease-related proteins and small molecules in pharmaceutical research and medical diagnosis. In addition, mass spectrometry (MS) can be particularly powerful when analyzing molecules with complex structures, such as posttranslationally modified proteins. Among various MS approaches, high-resolution multistep tandem MS (MS-MS) is an emerging methodology for accurate identification of complex molecules. In this article, we describe a new approach for mass analysis with enhanced quantitative capability combined with high-resolution multistep MS-MS, where the dynamic range of quantitation covers four orders of magnitude.

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Analysis by mass spectrometry (MS) of integral membrane proteins and those associated with membrane is an important aspect of proteomics.

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A simple HPLC procedure is described for the determination of bendroflumethiazide (BMFT) in pharmaceutical formulations and urine samples. No interferences from common additives or other drugs frequently administered with BMFT or from endogenous compounds in urine samples were found. The lack of an organic solvent in the mobile phase reduces the risk of environmental contamination and human toxicity.

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LC-MS-MS has become a widely used technique for the fast and sensitive quantitation of small molecules. In this article, this approach has been extended to high-throughput quantitative LC-MS-MS analysis under GLP applications for a drug candidate in development from preclinical animal studies through clinical development.

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Melamine is an organic base and a trimer of cyanamide, with a 1,3,5-triazine skeleton. Melamine can react with formaldehyde to produce melamine resin, a very durable thermosetting plastic, and melamine foam, a polymeric cleaning product. Some end products made from melamine include countertops, dry erase boards, fabrics, glues, housewares, and flame retardants. Melamine is also one of the major components in Pigment Yellow 150, a colorant in inks and plastics.

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Multidimensional liquid chromatography (MDLC) techniques are essential for the separation of highly complex proteomic samples. Advantages of off-line MDLC techniques over on-line approaches include high flexibility in choice of column dimensions and mobile-phase compositions, and the ability to reanalyse sample fractions. Here we present a fully automated off-line two-dimensional chromatographic approach for the analysis of proteomic samples using an UltiMate 3000 system optimized for proteomics MDLC.

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The pyrolysis fragments are first refocused on the top of the GC column, then separated and finally detected by the MS. At the end of the GC run the SEC flow is resumed again and the entire process is repeated.

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It makes intuitive sense - the higher the sensitivity of an inductively coupled plasma–mass spectrometry (ICP-MS) system, the lower the detection limit. But there are many factors that affect the detection limit for a given isotope in a given sample. These factors include sensitivity, background noise, and interferences.

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Demonstrating the suitability of a new wax stationary phase for GCxGC analysis of essential oils

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It makes intuitive sense - the higher the sensitivity of an inductively coupled plasma–mass spectrometry (ICP-MS) system, the lower the detection limit. But there are many factors that affect the detection limit for a given isotope in a given sample. These factors include sensitivity, background noise, and interferences.

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In June of this year, the 30th meeting in the International Symposium in Capillary Chromatography series will convene in Dalian, People's Republic of China. The meeting promises to be a major celebration of separation science, and the separation science community has thrown its weight behind this initiative. The meeting is held under the auspices of the "International Organization for Promotion of Microcolumn Separations" and the "Chinese Academy of Science," with support from various organizations in China. Combined with the "4th Comprehensive Two-dimensional Gas Chromatography Symposium" and the "16th Chinese Symposium and Exhibition on Chromatography," the conference will offer many opportunities to present both international and regional accomplishments in chromatography. During the period of the symposia an exhibition will be held to showcase newly developed instruments and reagents from manufacturers around the world.

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This article describes the development of a routine method to analyse epoxidized soybean oil (ESBO) in baby food...

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The complexity of the systems that are used vary from standard GC configurations to assess the effectiveness of protective clothing to trace analysis of biomedical samples with complex GC configuration.

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There are many misconceptions about what it means to perform fast gas chromatography (GC) and what the term fast GC implies. Fast GC is often associated with the use of hydrogen as a carrier gas and, although this is certainly a good approach, it is not always necessary to shorten the analysis time. A second misconception is that changing column dimension results in time-consuming method development. Using high-efficiency GC columns can greatly reduce the analysis time and when coupled with the method translation software, the time spent on method development can be greatly minimized.

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Metabolomics is a developing analytical approach that is growing rapidly in importance as a tool to improve diagnosis and treatment of disease, as well as to speed up the drug development process. Unlike genomics or proteomics, which only reveal part of what might be happening in a cell, metabolomic profiling can give an instantaneous snapshot of the entire physiology of that cell. This article describes the challenges associated with metabolomics research and new tools developed to overcome them.

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Carbonyl compounds, including low molecular weight aldehydes and ketones, have environmental and health concerns; for example, short-term exposure to aldehydes can irritate the eyes, skin, and upper respiratory tract. Motor vehicles emit reactive hydrocarbons that undergo photochemical oxidation in the atmosphere, which generates formaldehyde and other carbonyls. In addition, formaldehyde contributes to the formation of photochemical ozone. California Air Resources Board (CARB) Method 1004 (1) provides an analytical method for the automotive industry to monitor 13 carbonyl compounds in engine exhaust. US EPA Method TO-11A (2) and Method 8315 (3) monitor atmospheric formaldehyde and 14 other carbonyl compounds and are used for a variety of environmental and occupational health purposes. In these methods, carbonyl compounds are trapped as the dinitrophenylhydrazine (DNPH) derivatives before analysis by HPLC.

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The evaluation of the state of a biological sample before starting the complex analyses is a crucial step in proteomics studies. This paper compares planar polyacrylamide gel electrophoresis (SDS-PAGE) and capillary on-the-chip SDS GE (CGE-on-the-chip) in terms of the speed of analysis, sensitivity and flexibility. Snake venoms, which are heterogeneous with high bioactivity and consist mainly of proteins with a molecular weight mass range below 100 kDa, were investigated. CGE-on-the-chip was found to be a faster and more stable technique, providing more information than classical SDS-PAGE. CGE-on-the-chip was also capable of detecting many compounds over a broad molecular weight mass range whereas the SDS-PAGE is more time-consuming and provides acceptable resolution either in the very low (below 17 kDa) or in the mid- to high-molecular mass region (16–200 kDa) depending on the gel/buffer-system selected.

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Victor U. Weiss and Günter Allmaier from TU Vien discuss how combining molecular beacons with chip capillary electrophoresis (CE) offers scope to investigate viral RNA replication and improve gene therapy delivery systems.

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Very low level detection of mycotoxins in the agriculture products has become increasingly important. Mycotoxins are very resistant fungal metabolites that can remain in foods after processing and, sometimes, even after cooking. They are considered potent carcinogens and can be found in many varieties of foods. Of the mycotoxin class, aflatoxins are considered especially harmful, being both acutely and chronically toxic. Aflatoxin B1 and B2 are some of the most potent hepatocarcinogens known. Along with aflatoxins G1 and G2, even extremely low levels of these aflatoxins in the diet are important public-health concerns. With this in mind, this application note describes a specific, robust HPLC method for the low-ppb detection of aflatoxins B1, B2, G1 and G2 in corn.

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Analysis of biological samples frequently involves the identification of peptides from low amounts of complex samples. Confident identification of these peptides requires rapid generation of high quality, high sensitivity MS and MS–MS data. The maXis TOF mass spectrometer incorporates novel technical innovations, which together produce an unprecedented level of data quality, resulting in a significant increase in the number of peptides identified from challenging samples.

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The use of dual polarization interferometry (DPI) to measure the behaviour of alkyl-modified surfaces under different solvent regimes is described. The empirically observed and modelled behaviour of grafted long alkyl chain adlayers on a silica surface were in good agreement. The empirical data was also compared with data using analogous systems and these also matched well. This approach has the potential to gain much greater insight into the behaviour of reversed-phase (RP) columns and could help to design column surfaces that are resistant to phase collapse.

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WAX type columns are the industry standard analyzing a wide range of compounds with polar functional groups. The new Agilent DB-WAX Ultra Inert GC column is presented.

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This article describes the use of combined ion chromatography-mass spectrometry (IC–MS) and ion chromatography-inductively coupled plasma mass spectrometry (IC-ICP–MS) to analyse potentially harmful compounds.

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In addition to the universal detectors used in gas chromatography (GC), selective detectors have also played an important role in the rapid spreading of the utilization of the technique. Probably the most important selective GC detector is the electron-capture detector, with a very high sensitivity to organic compounds containing chlorine and fluorine atoms in their molecules. The electron-capture detector had a vital role in environmental protection and control - its use helped to prove the ubiquitous presence of chlorinated pesticides in nature and halocarbons in our atmosphere, and made us aware of the global extent of pollution. It was the electron-capture detector that made concentration ranges of parts-per-billion (ppb: 1:109) or even parts-per-trillion (ppt: 1:1012) detectable. Today, these terms are used routinely without realising how formidable such a sensitivity really is: 1 ppb means that a spaceship (or a UFO, depending upon one's inclination) could pick up a particular family of six from..