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Separation of Heat-Degraded Recombiant Human EPO Protein
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| By
Phu Duong
,
Agilent Technologies, Inc.
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Erythropoietin protein (EPO) is a glycoprotein hormone found in plasma. It is a cytokine for erythrocyte (red blood cell) precursors in the bone marrow.
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Scherzo SS-C18's Novel Multi-Mode Stationary Phase Shows Improved Retention and Resolution of Neurotransmitters
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| By
Bhavana Verma
,
Itaru Yazawa
,
Imtakt USA
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Simultaneous HPLC analysis of neurotransmitters can be challenging due to the similarity of their structures.
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Improving Intact lgG Separations with Aeris WIEDPORE Core-Shell HPLC–UHPLC Columns
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| By
Michael McGinley
,
Deborah Jarrett
,
Jeff Layne
,
Phenomenex, Inc.
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A new widepore core-shell HPLC–UHPLC column (aeris WIDEPORE) has been introduced that is specifically designed to improve protein separations.
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Using Longer Aeris PEPTIDE Core-Shell HPLC–UHPLC Columns for Improved Peptide Mapping
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| By
Michael McGinley
,
Deborah Jarrett
,
Jeff Layne
,
Phenomenex, Inc.
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A new 3.6 µm 100 Å HPLC–UHPLC column (Aeris PEPTIDE) has been introduced that is specifically designed to improve separations of peptide and peptide mapping applications.
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Analysis of Saccharides by Hydrophilic Interaction Chromatography (HILIC) Using TSKgel NH2-100 Columns
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| By
Atis Chakrabarti
,
Tosoh Bioscience LLC
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Saccharides are fundamental substances that express various bioactivities and may exist independently or form complexes with proteins or lipids.
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Guidelines for Routine Use and Maintenance of Ultra Performance Size Exclusin and Ion Exchange Chromatography Systems
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| By
Paula Hong
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Kenneth J. Fountain
,
Waters Corporation
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For the analysis of biotherapeutics, size-exclusion and ion-exchange chromatography are typically conducted under native separation conditions, requiring high ionic strength, 100% aqueous eluents.
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Analysis of Paralytic Shellfish Toxins
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| By
Saji George
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Maria Ofitserova
,
David Mazawa
,
Pickering Laboratories, Inc.
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The paralytic shellfish toxins are a group of 18 secondary metabolites deposited in bivalve mollusks by dinoflagelates. Dinoflagelate blooms are seasonal, occurring during warm months.
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Agarose-Heated Transfer Lines
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| By
Wyatt Technology Corporation
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Agarose is a polysaccharide produced from seaweed that forms a gel at room temperature. The characteristics of agarose gels depend on the agarose concentration, solvent, weight-average molar mass, and molar mass distribution.
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One-Step Extractio and Concentration for Identifying Pharmaceuticals and Personal Care Products in Water, Biosolids, and Solids
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| By
FMS, Inc.
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Over the last decade the use of Pharmaceuticals and Personal Care Products (PPCPs) has doubled in the United States. As a result, PPCPs have entered the environment through both human activity and as by-products from manufacturing, agricultural activities, medical use and veterinarian facilities.
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Screening for Pyrethroid Insecticides in Sediment Samples by GC–MS-MS
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| By
Ed George
,
Bruker Daltonics, Chemical Analysis Division
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A simple screening method for Pyrethroid insecticides in sediment samples is described. Electron impact ionization (EI) with tandem MS-MS in combination with programmed temperature vaporization injection (PTV) were used in order to obtain excellent specificity and low limits of detection.
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Enhancing Recoveries and Maximizing Throughput of Semi-Volatile Organics using the Direct-to-GC-Vial Concentrator Tube and DryVap Concentrator System
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| By
Michael Ebitson
,
David Gallagher
,
Horizon Technology, Inc.
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The purpose of this study is to determine how the Direct-to-GC vial concentrator tube and the DryVap ® Concentrator System can optimize the recoveries for both low and high boiling point semi-volatile compounds.
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Microwave Assisted Extraction of Dioxins and Furans Compared to Soxhlet
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| By
Melissa Lightner
,
Milestone Inc.
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Microwave assisted extraction (MAE) offers significant benefits over traditional soxhlet extraction for dioxins and furans determination from environmental samples including higher sample throughput, time savings, reduced solvent and great reproducibility.
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Purge-and-Trap GC Analysis of Methane in Water Samples Associated with Hydraulic Fracturing
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| By
Laura Chambers
,
Gary Engelhart
,
Scott Hazard
,
OI Analytical
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Shale gas reservoirs, such as the Marcellus shale reserve in Pennsylvania and Barnett shale reserve in Texas are a growing source of natural gas in the United States.
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Fast Cap IC Determinations of Inorganic Anions and Cations in Drinking Water
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| By
Fei Pang
,
Terri T. Christison
,
Khalil Divan
,
Thermo Fisher Scientific
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The determination of common inorganic anions and cations in drinking water is important due to the toxicity of anions (e.g., fluoride, nitrite, and nitrate) and secondary contaminants (e.g., chloride and sulfate) which can affect the water's aesthetics.
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Rapid On-Site Screening of Environmental VOCs in Soil using Solid Phase Microextractio and a person-Portable GC–MS
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| By
Tiffany C. Wirth
,
Charles S. Sadowski
,
Douglas W. Later
,
Torion Technologies, Inc.
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Volatile organic compounds (VOCs) in soil were rapidly extracted and concentrated using solid phase microextraction (SPME) followed by on-site analysis and identification with the TRIDION-9 portable gas chromatograph – toroidal ion trap mass spectrometer (GC-TMS). 37 VOCs were resolved and analyzed quickly in under 3 min.
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Comparison of BTEX in Olive Oils by Static and Dynamic Headspace
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| By
Roger Bardsley
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Teledyne Tekmar
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The benefits of olive oil as part of a healthy diet reaches back to the 1950's. Methods were developed to determine benzene, toluene, ethylbenzene, xylenes and styrene (BTEXS) by static headspace methods.
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A Variety of Agilent ZORBAX RRHD Phases Offers Selectivity Options for the Determination of Anthocyanins in Blueberries with UHPLC/MS
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| By
Anne E. Mack
,
Agilent Technologies, Inc.
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Blueberries are extracted into acidified methanol and analyzed for anthocyanins with a methanol/formic acid gradient via UHPLC/MS; four different Agilent ZORBAX RRHD stationary phases are quickly evaluated.
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Chromatoaphy Methods for Determining Carbohydrates in Coffee
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| By
Lipika Basumallick
,
Jeffrey S. Rohrer
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Coffee carbohydrates constitute the major part (at least 50% of the dry weight) of raw coffee beans, and are good tracers for assessing the authenticity of instant coffee.
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Impurities in Wines by GC–MS
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| By
Benedicte Gauriat-Desroy
,
Eric Phillips
,
Stacy Crain
,
Trisa Robarge
,
Thermo Fisher Scientific
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By identifying maturation tracers and molecules commonly responsible for taste defects, gas chromatography–mass spectrometry (GC–MS) augments expert opinion with objective and quantitative information. When using a solid phase micro extraction (SPME) method, GC–MS requires very small sample sizes and a minimum of sample preparation while providing rapid analysis of target molecules. GC–MS can provide an automated technique with repeatable results for detecting all of these compounds.
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Quantitation of Omega Fatty Acids by HPLC and Charged Aerosol Detection
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| By
Marc Plante
,
Bruce Bailey
,
Ian Acworth
,
Thermo Fisher Scientific
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Omega-3 and -6 fatty acids are essential compounds required for normal growth. Omega-3 consumption is purported to have a number of health benefits, e.g., cancer prevention, cardiovascular disease prevention, and improved immune function. Although both omega-3 and -6 fatty acids can give rise to eicosanoid-signaling molecules (prostaglandins, prostacyclins, thromboxanes, and leukotrienes), the omega-6 eicosanoids are generally proinflammatory. A person's diet requires a balance of omega fatty acids at suitable levels.
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Faster, More Sensitive Determination of Carbamates in Drinking Water
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| By
Chen Jing
,
Xu Qun
,
Jeffrey S. Rohrer
,
Thermo Fisher Scientific
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U.S. EPA Method 531.2 describes the determination of widely used carbamate pesticides in raw surface water using HPLC with fluorescence detection following postcolumn derivatization, which enhances method sensitivity and selectivity as compared to UV absorbance detection.
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Determination of Dyes in Fish Tissue by HPLC/UV
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| By
Daniel A. Fonseca
,
Brian Kinsella
,
Thomas August
,
Craig A. Perman
,
Thermo Fisher Scientific
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Various triarylmethane and fluorescent dyes are used in aquaculture as antibacterial, antifungal, and anthelmintic agents for the treatment of fish disease. The FDA has banned the importation of certain fish from several countries due to possible contamination of these food products.
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Liposome Characterization by FFF-MALS-QELS
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| By
Wyatt Technology Corp.
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Liposomes are made of lipid bilayers and are often used in drug delivery by encapsulating the core with therapeutic drugs. During liposome research, formulation, manufacturing, and quality control, it is of great importance to monitor liposome size and encapsulation. Field flow fractionation (FFF) with the concomitant use of multi-angle light scattering (MALS) and quasi-elastic light scattering (QELS, aka dynamic light scattering) is an ideal tool for such characterization. Figure 1: Hydrodynamic radius (a) and root-mean square radius (b) plotted against elution time overlaid with 90° LS signals for empty liposome sample (red) and filled liposome sample (green). The Rh and Rg values are determined by the respective QELS and MALS detectors. The results from duplicate runs of each sample are shown here to demonstrate the reproducibility of the FFF?MALS?QELS analysis. Here, we report the analytical results of two liposome samples, one empty, and one filled.
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New HPLC/UHPLC Assay Methods for Impurities in Tetracycline
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| By
Suparerk Tukkeeree
,
Jeffrey S. Rohrer
,
Thermo Fisher Scientific
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Tetracycline (TC), a common antibiotic used to treat urinary tract infections, acne, gonorrhea, and other conditions, yields a toxic degradation product, 4-epianhydrotetracycline (EATC). General Chapter 226 of the U.S. Pharmacopeia and National Formulary (USP-NF), referred to by monographs for epitetracycline and drug products containing tetracycline hydrochloride (TC-HCl), prescribes an antiquated assay for EATC impurity in TC.
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LC–MS-MS Method for the Determination of Enalapril and Enalaprilat fro Human Plasma Using SOLA
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| By
Ken Meadows
,
Thermo Fisher Scientific
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A liquid chromatography tandem mass spectrometry method for enalapril and enalaprilat from human plasma has been developed using Thermo Scientific SOLA cartridges. Sample preparation is fast, efficient, and reproducible giving excellent recovery levels for each compound.
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New Generation Monolithic Silica Columns for Fast, High Resolution Drug Separations without High Pressures
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| By
Karin Cabrera
,
Egidijus Machtejevas
,
Merck Millipore
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Using a novel new-design monolithic silica column (Chromolith? HighResolution RP-18e), fast, high resolution separations were achieved for various drug mixtures without the high pressures characteristic of modern particulate technology.
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Analysis of Over 15 Million Dalton Polymers by Aqueous SEC Method
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| By
Kanna Ito
,
Shodex Showa Denko America, Inc
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Size exclusion chromatography (SEC) is a simple HPLC technique used for the molecular weight (MW) distribution analysis of polymers. Several manufacturers provide SEC columns with different base materials and various pore sizes to cover a wide range of polymer analysis.
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UHPLC Column Protection Dramatically Extends UHPLC Column Performance and Lifetime
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| By
J.T. Presley III
,
Tom Cleveland
,
Jeff Layne
,
Phenomenex
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UHPLC columns can significantly improve chromatographic separations, but they also present unique challenges. Once the UHPLC system components are optimized, perhaps your greatest concern is protecting the column from the damaging effects of microparticulates and sample contaminants.
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Resistive Glass Inlet Tubes Increase Ion Throughput
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| By
Paula Holmes
,
Bruce N. Laprade
,
Photonis USA
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Resistive glass tubes and plates are designed to guide ions by generating a uniform electric field. PHOTONIS resistive glass products are composed of a proprietary lead silicate glass that has been specially processed to create a resistive layer at the surface. The resistivity can be varied over several orders of magnitude to suit the specific application.
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Improved Internal Diameter Control of Tubing Used for Gas Chromatography
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| By
Joe Macomber
,
Roland Fischer
,
Polymicro Technologies, A subsidiary of Molex Incorporated
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Synthetic fused silica capillary tubing is used in the manufacture of most gas chromatography (GC) columns. In this note, we discuss recent advances in the dimensional control of the most popular tubing sizes.
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HPLC Method for the Separation of Nine Key Components of Milk Thistle
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| By
Dave Bell
,
Supelco/Sigma-Aldrich
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Silymarin, derived from the milk thistle plant, has been used as a natural remedy for the treatment of a number of liver diseases as well as in the protection of the liver from potential toxins. More recently, silymarin has been connected to antitumor promoting activity (1). It is therefore of interest to have available analytical methods for the analysis of silymarin components in various matrices.
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Analysis of Multiple Classes of Cigarette Smoke Constituents by GCxGC-TOFMS
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| By
Elizabeth Humston-Fulmer
,
Joe Binkley
,
LECO Corporation
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GCxGC-TOFMS provided a comprehensive analysis of tobacco smoke. Individual smoke constituents across several target compound classes were extracted, chromatographically resolved, then identified and quantified with mass spectral detection.
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Establishing USP Rebaudioside A and Stevioside Reference Standards for the Food Chemicals Codex
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| By
Yi Dang
,
Jeffrey Moore
,
Gloria Huang
,
Markus Lipp
,
Barbara Jones
,
James C. Griffiths
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The United States Pharmacopeial Convention (USP) publishes the Food Chemicals Codex (FCC), which is a compendium of food ingredient documentary standards (monographs) that provide tests, procedures, and acceptance criteria to indicate the safety and quality of a food ingredient. Physical reference standards can be associated with the procedures of an FCC monograph and the reference standards are needed for conducting the procedures. This article describes characterization and collaborative testing of new USP rebaudioside A and stevioside reference standards and their suitability for intended uses in the FCC rebaudioside A monograph.
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Trace Metabolic Profiling and Pathway Analysis of Clomazone Using LC–MS-MS and High Resolution MS
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| By
Wei Zou
,
Hagai Yasuor
,
Albert J. Fischer
,
Vladimir V. Tolstikov
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Detection, analysis, and characterization of low-abundant metabolites remain an unresolved problem in metabolic studies. In this study, we report a novel approach to address this challenge. The current methodology is derived from the predictive multiple reaction monitoring (pMRM) mode available on triple-quadrupole linear ion trap mass spectrometry (MS) systems. The pMRM mode offers the highest sensitivity among various acquisition modes for studying trace levels of metabolites of the herbicide clomazone in plants. Additionally, this method allows for the identification of positional isomers of metabolites.
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