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The Clean Air Act (CAA) (1) provides the U.S. Environmental Protection Agency authority to enforce regulations limiting emissions of volatile organic compounds (VOCs) and other air pollutants. The Compendium of Methods for the Determination of Toxic Compounds in Ambient Air includes a variety of sampling and analysis methods (2, 3), including use of single- and multi-sorbent tubes. Concentrating a large volume of sample onto a sorbent tube, followed by thermal desorption onto a GC column provides an efficient, cost-effective means of monitoring VOCs at parts per billion (ppb) or parts per trillion (ppt) levels.

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Evaporation-free extraction (no drying down) is highly desirable because of its reduced cost and pollution, higher speed, and less possibility for contamination and conversion. Presented in this article are four types of evaporation-free extraction that are widely applicable. The first one is for the determination of didanosine over the range of 25.02–2502.00 ng/mL by injecting solid-phase extraction (SPE) eluate directly. The second is for the determination of betamethasone phosphate over the range of 2.51–250.60 ng/mL by injecting SPE eluate after pH adjustment. The third is for the determination of sumatriptan over the range of 0.99–99.40 ng/mL based upon SPE with high organic washing and low organic elution. The fourth is based upon automated dilution after protein precipitation for the determination of raloxifene-4'-glucuronide and raloxifene-6-glucuronide over the ranges of 2.02–202.40 ng/mL and 0.40–39.95 ng/mL, respectively.

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LC-MS monitoring of the drug clozapine is detailed along with a description of the overall system architecture, workflow, and maintenance routines that spport a large-scale drug monitoring program.

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Microemulsion-based HPLC (MELC) is a recent development offering reduced sample preparation times for complex samples and generic separation conditions applicable to a wide range of solutes. This article introduces the concepts of MELC and discusses the possible benefits and future applications.

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Various modes of capillary electrochromatography (CEC) for the separation of enantiomers on immobilized cyclodextrin derivatives are described. The following techniques have been used: (i) open-tubular electrochromatography (o-CEC), (ii) packed electrochromatography (p-CEC) and (iii) monolithic electrochromatography (rod-CEC). Three different strategies to prepare enantioselective cyclodextrin-coated chiral monoliths are described. The advantages and disadvantages of the various methods are outlined.

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A detection method based upon aerosol charging was examined for its applicability and performance with high performance liquid chromatography.

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Microemulsion-based HPLC (MELC) is a recent development offering reduced sample preparation times for complex samples and generic separation conditions applicable to a wide range of solutes. This article introduces the concepts of MELC and discusses the possible benefits and future applications.

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This month's instalment of "MS in Practice" provides a slightly different view of how practitioners employ the skills of interpretation that have been the focus in recent columns.

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A variety of chromatographic sorbents are commercially available for reversed-phase liquid chromatography (RPLC) and while many of these columns are nominally similar, in practice the columns may provide significantly different separations.

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Food quality differences are dependent on botanical and geographical origins of primary food ingredients as well as storage and handling. Quality assessment for food materials, including cocoa and olive oil, is demonstrated by applying two-dimensional gas chromatography (GC×GC) combined with time-of-flight mass spectrometry (TOF-MS) and pattern recognition.

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This article describes the method development and performance characteristics of the validated LFI assay and evaluates stability in human plasma.

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Micellar liquid chromatography (MLC) is a reversed-phase liquid chromatographic mode with a solution of surfactant forming micelles as the mobile phase. The interaction of solutes with the stationary phase coated with surfactant monomers, combined with the increased solubilization capability of micelles, have profound implications with regard to retention, selectivity and efficiency. Practical steps that a chromatographer involved in MLC should consider when developing an analytical procedure are described, including mobile phase preparation, column conditioning and cleaning.

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Corn stover is the above-ground portion of the plant minus the kernels and it accounts for a large percentage of the global supply of lignocelluosic biomass available as feedstock for fermentation systems used for biofuel production.

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In the past decade, supercritical fluid chromatography (SFC) has been established as a cost-effective, sustainable, and green purification technology for pharmaceutical and related industries.

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Semiquantitative elemental analysis by ICP-MS is a powerful tool for quick screening of unknown samples for a wide range of elements.

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Amino Acids analysis method according to European Pharmacopoeia to support development and production of biopharmaceuticals.

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The authors evaluate a method for detecting pesticide residues in dandelion root powder.

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The 2013 Emerging Leader in Chromatography Award is granted to Davy Guillarme. Here we look at his career and accomplishments so far.

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Recent advances in green chemistry have made multivariate experimental design popular in sample preparation development. This approach helps reduce the number of measurements and data for evaluation and can be useful for method development in gas chromatography.

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We explore the impact of two different stationary phases and ion-pair reagents on the retention behavior of a therapeutic peptide using reversed-phase liquid chromatography. This information is of fundamental importance for the development of reliable, selective, and fast analytical methods able to separate and identify the target peptide.

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Helium is running out, the worldwide demand is exceeding current production levels. Learn how Hydrogen could be your perfect replacement for Helium.

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Examples from food science illustrate the usefulness of chemometrics techniques like pattern recognition, regression, and classification.

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A rapid LC–MS method using ESI coupled with SIM-MS for analysis of humulone and isohumulone content in beer is described.

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Employing ion mobility at atmospheric pressure without vacuum enables coupling to high-resolution mass analyzers. High performance ion mobility–orbital trap mass spectrometry (HPIM-OT-MS) is a useful alternative for separating isomers, such as isomeric metabolites seen in drug discovery.

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The authors investigated the two most popular types of interfaces for benchtop LC–MS systems – the particle interface and the atmospheric-pressure ionization interface – to learn how the information obtained separately from the two can be complementary.

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In this edition of The LCGC Blog, André Striegel provides advice on how to prepare for your first talk or presentation at a scientific conference.

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Understanding separation principles is the key to success. Here's why.

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This month's "Directions in Discovery" gives a brief overview of turbulent- flow liquid chromatography, a technique for fast separations. Two examples demonstrate the use of the technology for high-throughput bioanalytical separations in drug discovery.

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High performance anion-exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD) is a potential method of choice for the analysis of carbohydrates.