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Inside the Personalized Medicine Toolbox: GCxGC-Mass Spectrometry for High-Throughput Profiling...The authors present results that suggest that high-throughput, high-coverage profiling capabilities, such as those afforded by GCxGC-TOF-MS, can impact the development of personalized medicine.
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Method 525.2 Update: Analyte Recoveries with New CCL3 CompoundsEPA is updating method 525.2. The CCL3 includes 104 analytes. UCT has evaluated the recoveries of these compounds, including the current list, using proposed changes to the method with the C18-based UCT ENVIRO-CLEAN? 83 mL Extraction Cartridge ECUNI525.
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Separation, Identification, and Quantitation of Water-Soluble Vitamins by HPLCThe authors set out to perform a separation of seven water-soluble vitamins without the use of ion-pair reagents.
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Extraction and Detection of Antibiotics in the Rhizosphere MetabolomeRoot diseases caused by soilborne plant pathogens are responsible for billions of dollars of losses annually in food, fiber, ornamental, and biofuel crops. The use of pesticides often is not an option to control plant diseases because of economic factors or potential adverse effects on the environment or human health. For this reason, many Americans are now buying pesticide-free organic foods. Organic agriculture has few options for controlling pests and thus must make full use of natural microbial biological control agents in soils that suppress diseases.
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Direct Determination of Endothall in Water Samples by IC–MSEndothall is a widely used herbicide for both terrestrial and aquatic weeds. Exposure to endothall in excess of the maximum contamination level (MCL) can cause illness. Endothall is regulated by the U.S.
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Approaches to Singleton Achiral Purification of Difficult Samples for Discovery Research SupportSeveral approaches for purifying difficult samples more efficiently for discovery research support are mentioned in this paper. These approaches use mass triggered HPLC on various specialty columns.
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LC Column Technology: The State of the ArtIn this extended special feature to celebrate the 30th anniversary edition of LCGC Europe, leading figures from the separation science community explore contemporary trends in separation science and identify possible future developments. We asked key opinion leaders in the field to discuss the current state of the art in liquid chromatography column technology, gas chromatography, sample preparation, and liquid chromatography instruments. They also describe the latest practical developments in supercritical fluid chromatography, 3D printing, capillary electrophoresis, data handling, comprehensive two‑dimensional liquid chromatography, and multidimensional gas chromatography.
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Analysis of Melamine and Cyanuric Acid in Food Matrices by LC–MS-MSIn March 2007, several North American manufacturers of pet food voluntarily issued nationwide recall notices for some of their products that were reportedly associated with renal failure in pets. The raw material wheat gluten, used to manufacture the pet food, was imported from China and was identified as the source of contamination.
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Extending the Hydrocarbon Range for the Analysis of Soil Gas Samples Using Automated Thermal Desorption Coupled with Gas Chromatography–Mass SpectrometryThis study describes the recovery of compounds above the boiling point of naphthalene achieved by optimizing the thermal desorption chemistry for the determination of volatile organic compounds ranging from C3 to C26 in soil gas samples using Method TO-17. Figures of merit such as breakthrough, precision, linearity, and detection capability are presented, in addition to an evaluation of its real-world capability at sites with moderate diesel and semivolatile polynuclear aromatic hydrocarbon (up to pyrene) contamination, in the presence of high humidity. This research has provided a means to determine a more representative composition of soil gas.
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Sulfated β-Cyclodextrin as Chiral Mobile Phase Additive for Ultrahigh-Pressure Liquid ChromatographyA fast enantiomeric separation of a chiral aromatic amine was achieved, using ultra high pressure liquid chromatography and highly sulfated β-cyclodextrin (S-β-CD) as a chiral additive in the mobile phase. The stationary phase consisted of a core shell support with a particle size of 2.7 µm. Under these conditions the baseline separation was obtained within 2.5 min. The influence of the concentration of the additive, along with the thermodynamics of the separation, were studied. Molecular mechanics calculations were consistent with the experimental data for the order of elution, providing further evidence of these interactions. The enantiomeric separation at high temperature (90 °C) using only water as mobile phase also was achieved for the first time.
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On-Site Sample Preparation Using MEPS for Waste Water AnalysisMEPS uses a barrel insert and needle (BIN) device to reduce Solid-Phase Extraction (SPE) to a micro-scale suitable for small volume samples and for the online adaptation of conventional SPE techniques. Because the SPE cartridge (BIN) is incorporated into the needle assembly of a gas-tight syringe, MEPS is also a simple field-portable SPE device that may be operated manually without need for sampling pumps or, alternatively, may be incorporated into robotic samplers. MEPS devices are of glass and stainless steel construction allowing them to be fully immersed for sampling at depth or, alternatively, used at needle depth to avoid perturbing the stream from which the sample was drawn. An extension pole allowed MEPS to be used to sample back along pipes or down inspection vents. When sampling from drainage pits and open sumps, there was minimal requirement to remove grates to gain access. An extension pole also allowed sampling from outflows that were offensive and could be readily adapted for safe sampling of..
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Fast Gradient LC Using Your Existing InstrumentationTransforming "standard" gradient HPLC systems into extremely fast gradient systems is readily achievable with proper application of chromatographic principles, particularly temperature control, combined with utilization of advanced HPLC columns. Bottom line: You don't have to buy a new LC to achieve ultra high quality and speed!
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Chemometrical Experimental Design-Based Optimization Studies in Capillary Electrophoresis ApplicationsA synopsis of our work detailing the use of chemometric response surface methodology (RSM) in two capillary electrophoresis (CE) studies is described.
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Rigid Porous Polymer Monoliths as Stationary Phases and SupportsThe never-ending quest for separation media that enable efficient high speed/high throughput chromatography has led to the design of stationary phases in monolithic formats with both vastly improved mass transfer properties and reduced discontinuity. Historically, porous polymer monoliths have first emerged in the late 1980s/early 1990s followed by their silica-based counterparts in the mid 1990s. The common denominator for both organic and inorganic monoliths was originally their use in HPLC columns. However, the range of applications of monolithic materials grew significantly since their early times. This short review summarizes information about monoliths produced in different shapes such as discs, tubes, columns, polymer layer open tubes (PLOT capillaries), and microfluidic devices, and presents selected applications including chromatographic separations, sample preparation, and enzyme immobilization.
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Inside the Personalized Medicine Toolbox: GCxGC-Mass Spectrometry for High-Throughput Profiling...The authors present results that suggest that high-throughput, high-coverage profiling capabilities, such as those afforded by GCxGC-TOF-MS, can impact the development of personalized medicine.
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Analysis of Fusarium Toxins Using LC–MS-MS: Application to Various Food and Feed MatricesCo-occurrence of several mycotoxins (deoxynivalenol, zearalenone, T-2-toxin, HT-2 toxin) produced by field fungi, such as Fusarium graminearum and Fusarium culmorum, requires several analysis methods for their characterization. A reliable method for the determination of type A- and B-trichothecenes and zearalenone in cereal-based samples is presented. To achieve optimal mass spectrometric detection, electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) were compared. Best results were obtained with ESI by implementing a two-period switching for the ionization polarity. The limit of quantification differs for each individual substance within the range 1–10 ppb. Mean recoveries using a standardized clean-up procedure were in the 54–93% range.
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Performance Qualification of HPLC Instrumentation in Regulated LaboratoriesWith the forthcoming USP monograph <1058>, many laboratories are in the process of reexamining their high performance liquid chromatography (HPLC) instrumentation qualification practices. This article demystifies the qualification procedures and proposes a well designed, easy and simple set of experiments upon which to establish internal standard operating procedures (SOPs) for the complete qualification of HPLC instruments. A key concept is the development of a consistent test system, comprised of premade test solutions, a prequalified HPLC column, standardized protocols, and validated software that can be prepared in-house or purchased commercially as a kit. This system can be applied to any HPLC system worldwide, to produce comparable test results under uniform conditions. The test system is designed to be rapid, with a comprehensive performance qualification being completed in about 2 h for isocratic, and 3 h for quaternary gradient systems.
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Solving Challenges with AAV Aggregate Analysis Using a Novel Size Exclusion Particle to Determine CQAsLearn the latest techniques for improved chromatographic performance and throughput of AAV analysis.
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CHIRALPAK® IC ™ - An Immobilized Polysaccharide Chiral Stationary Phase with a Unique Chiral SelectorA new, immobilized chiral stationary phase (CSP) based on a novel chiral selector for HPLC and SFC is described. Its unique selectivity as a complement to Daicel's other commercial immobilized polysaccharide CSPs is demonstrated.
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Chemical Warfare Agent Spectral Imaging for Real-Time Identification and LocalizationIn this article, the authors discuss the need for protection against chemical attacks and the role of passive imaging spectroradiometers in the detection of remote chemical agents.
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Facilitating Discovery of Prion Disease Biomarkers by Quantitative GlycoproteomicsThe authors examine MS-based methods to search for protein biomarkers of prion diseases from plasma samples.
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LC–MS-MS Determination of Malachite Green and Leucomalachite Green in Fish ProductsAlthough not currently used in U.S. or European aquaculture, malachite green (MG) is still an effective and inexpensive fungicide that is used in other countries, particularly in Asia. During metabolism, MG reduces to leucomalachite green (LMG) (Figure 1), which has been shown to accumulate in fatty fish tissues. Trace levels of MG and LMG residues continue to be found in fish products. In a 2005 report, MG was found in 18 out of 27 live eel or eel products imported from China to Hong Kong local market and food outlets, resulting in a government recall and destruction of all remaining products (1).
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Characterization of PEGylated Lysozyme by Size Exclusion and Ion Exchange ChromatographyPEGylation, the process by which polyethylene glycol (PEG) chains are attached to protein and peptide drugs is a common practice in the development of biopharmaceuticals to prolong serum half-life and improve pharmacokinetics of a drug. There is increasing demand for chromatographic methods to separate the modified isoforms from the native protein. This application note describes the use of size exclusion and ion exchange chromatography for the characterization of PEGylated lysozyme.
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Chemical Warfare Agents and Use of Thermal Desorption–GC–MS to Achieve Improved Trace-Level DetectionThis article discusses the analysis of a wide range of CWAs at current exposure limits and describes a number of recent beneficial developments in TD and associated analytical technologies for the identification and quantification of CWAs at these levels.
