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Practical Advice for High Throughput Ion Exchange Separations using Non-porous Particles
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| By
Andrew Coffey
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Agilent Technologies, Inc.
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Ion exchange is a perfect technique for analyzing large biomolecules such as proteins, peptides and oligonucleotides. These complex compounds contain numerous components (amino acids, nucleotides, glycans etc.) many of which possess a charged side chain or backbone.
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Characterization of Metabolites in Neat Rice Leaf Extracts Using High Resolution Time of Flight Mass Spectrometry Coupled to Gas Chromatography
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| By
Jeff Patrick
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LECO Corporation
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Plant materials contain a wealth of information on plant viability and health. The analysis of the metabolite contents of the leaves of various plants has been informative in the comparison of organisms.
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Direct Measurement of Mass Balance in the Digestion of a Protein
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| By
Christopher Crafts
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Bruce Bailey
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Ian Acworth
,
Thermo Fisher Scientific
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Selective cleavage of proteins by the enzyme trypsin helps characterize larger proteins. While MS provides structural information, quantitative analysis is often based on detection by UV at 214 nm.
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Glycan Analysis using HPLC with Charged Aerosol Detection and MS Detectors
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| By
Bruce Bailey
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Ian Acworth
,
Thermo Fisher Scientific
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Andy Hanneman
,
Wyeth BioPharma
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Simple, rapid and accurate methods have been developed for the analysis of simple carbohydrates including mono- or disaccharides, or as fairly small glycans (6–11 residues) liberated from glycoproteins using charged aerosol detection combined with mass spectrometry techniques.
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Molecular Weight Determination of Low-Molecular-Weight Heparins: SEC/MALS vs. SEC/UV-RI
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| By
Wyatt Technology Corporation
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Low-molecular-weight heparins (LMWHs) are obtained by fractionation or depolymerization of natural heparins. They are defined as having a mass-average molecular weight of less than 8000 and for which at least 60% of the total weight has a molecular mass less than 8000.
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The Analysis of 1,4-Dioxane for EPA Method 522 and UCMR 3
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| By
David Gallagher
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Michael Ebitson
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Horizon Technology, Inc.
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This application note will demonstrate the extraction of 1,4-dioxane from an aqueous matrix using option 1 of EPA Method 522 for 500 mL initial volume sample. It will make use of the SmartPrep Cartridge Extraction system to produce a valid initial demonstration of precision (IDP) and initial demonstration of accuracy (IDA).
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Low Level PAH Detection with an Extensive Dynamic Range
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| By
Yury Kaplan
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Ruben Garnica
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PerkinElmer, Inc.
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The analysis of PAHs in less than 16 min using hydrogen as carrier gas and the PerkinElmer? Clarus? SQ 8 GC/MS operating in SIM mode is presented. Detection limits down to 0.5 pg on-column and a wide dynamic range are reported.
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Enhanced Results of Diesel Range Organics Analysis with High-Temperature Gas Enhanced Chromatography
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| By
Kory Kelly
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Kali Tudela
,
Phenomenex, Inc.
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Diesel range organic (DRO) compounds have boiling points similar to diesel fuel (C10–C28), ranging from 170–430 ?C. These heavy compounds are amenable to GC-FID analysis; however, important considerations should be taken to ensure reproducible results over repeated injections.
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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
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Gary Engelhart
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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. Hydraulic fracturing or "fracking" involves pumping water, sand, and chemicals at extremely high pressure into deep underground wells to crack open hydrocarbon-rich shale formations and extract natural gas.
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UCMR 3 Low-Level VOC Analysis by Purge and Trap Concentration and GC-MS Using Selective Ion Monitoring
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| By
Holly Taylor
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Teledyne Tekmar
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The United States Environmental Protection Agency (US EPA) has established the Unregulated Contaminant Monitoring Program to collect data for contaminants suspected to be present in drinking water (1). The US EPA is currently proposing Unregulated Contaminant Monitoring Rule 3 (UCMR 3) which will collect data from January 2013 through December 2015. Because of the impact on public health and safety, it is vital to have a system that can detect and analyze for these compounds at low levels.
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Lowering Detection Limits for 1,4-Dioxane in Drinking Water Using Large Volume Injection in an Unmodified Splitless GC Inlet
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| By
Chris Rattray
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Jack Cochran
,
Chris English
,
Restek Corporation
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Concurrent solvent recondensation–large volume splitless injection (CSR-LVSI), an alternative to programmed temperature vaporization (PTV), typically requires a special GC inlet. The technique described here uses an unmodified split/splitless inlet with CSR-LVSI to lower detection limits for the analysis of 1,4-dioxane in drinking water.
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Rapid Sampling and Identification of Volatile and Semivolatile Organic Compounds by GC-TMS in Support of Decision Quality Data
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| By
Charles S. Sadowski
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Tiffany C. Wirth
,
Douglas W. Later
,
Torion Technologies, Inc.
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As analytical chemist(s), the data collected from samples we test represent information. That information may be required to direct environmental clean-up operations, help insure worker safety, or guide decisions for an emergency response to a chemical incident.
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Developing a UHPLC Method for UV-based Detection and Quantification of Primary Aromatic Amines in Low Concentrations
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| By
Edgar Naegele
,
Agilent Technologies, Inc.
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Ruediger Helling
,
State Health Institute for Health and Veterinary Affairs
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This application demonstrates that stringent sensitivity requirements for the detection of potentially harmful primary aromatic amines can be fulfilled when using an Agilent 1290 Infinity LC system equipped with the 1290 large volume injection kit.
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Rapid LC–MS-MS Analysis of Heterocyclic Amines in Salmon
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| By
Simon Lomas
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Jeff Layne
,
Phenomenex, Inc.
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Heterocyclic amines (HCAs) are a class of compounds that are formed when amino acids from meat proteins react with glucose and creatine under high-temperatures, as is associated with frying or grilling over an open flame (1–3). Studies have correlated the consumption of high levels of HCAs with an increased risk of some forms of cancer.
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Analysis of Antioxidants in Foods and Dietary Supplements using HPLC with Post-Column Derivatization.
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| By
Maria Ofitserova
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Sareeta Nerkar
,
Pickering Laboratories, Inc.
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Antioxidants protect cells from the damaging effects of free radicals and offer numerous benefits for human health. Many phenolic compounds found in plants, as well as some vitamins, exhibit antioxidant activity. Several colorimetric assays exist to measure the total antioxidant capacity, typically expressed as Trolox or Gallic acid equivalents.
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The Characterization of Sugar Beet Pectin using the EcoSEC GPC System Coupled to Multi-Angle Light Scattering, Quasi-Elastic Light Scattering, and Differential Viscometry
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| By
Amandaa K. Brewer
,
Tosoh Bioscience LLC
,
Hoa K. Chau
,
Arland Hotchkiss
,
Marshall L. Fishman
,
US Department of Agriculture
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The need to increase the use of low valued co-products derived from the processing of sugar beets has prompted the investigation of the structure of the pectin extracted from sugar beet pulp. The characterization of sugar beet pectin is essential as it has the potential to be used in the production of industrial products, e.g., as an emulsifying agent in food systems.
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Determination of Pesticide Residues in Red Wine by QuEChERS Extraction, Quick QuEChERS Cleanup and LC–MS-MS Detection
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| By
Xiaoyan Wang
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UCT, LLC
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Red wine is a challenging matrix that contains organic acids, sugars, phenols, and pigments such as anthocyanins. This application note describes a simple, fast, novel, and effective method to clean up red wine co-extractives.
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Extraction of Antioxidants from High Density Polyethylene (HDPE) By Pressurized Liquid Extraction (PLE)
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| By
FMS, Inc.
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Plastics and other polymers are used in a wide spectrum of applications from industrial usage to packaging, including the packaging of food and pharmaceutical products.
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Fast Screening Methods for Beta Blockers by HPLC with Agilent Poroshell 120 Columns
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| By
William Long
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Agilent Technologies, Inc.
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Beta blockers can be abused in sports involving little physical activity, such as archery, to reduce cardiac contraction, heart rate, and coronary blood flow.
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Radio Ion Chromatography
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| By
M. Espinosa
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Gomensoro S.A.
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J. Chesa-Jiménez
,
Instituto Tecnológico PET
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Beni Galliker
,
Alfred Steinbach
,
Andrea Wille
,
Metrohm International Headquarters
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Positron emission tomography (PET) is one of the most powerful noninvasive diagnostic tools for tracing organ functioning. Quality control of the short-lived radiopharmaceuticals is challenging, not at least because of the tough time limits, the radiation issue, and the near nanomole radiotracer quantities.
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The Scherzo Family Columns Simultaneously Separate Acidic and Basic Pharmaceutical Compounds and Resolve Better than a Standard C18 Column
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| By
Bhavana Verma
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Itaru Yazawa
,
Imtakt USA
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Compounds such as ibuprofen, chlorpheniramine, and allantoin are important in the field of pharmaceuticals and cosmetics. The analysis of acidic and basic compounds is particularly important but it is sometimes difficult to analyze both acidic and basic compounds on a single standard C18 column. Imtakt's Scherzo SM-C18 and Scherzo SW-C18 HPLC columns can separate acidic ibuprofen and basic chlorpheniramine simultaneously.
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Characterization of Polymeric Excipients by SEC-IR
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| By
Kanna Ito
,
Shodex/Showa Denko America, Inc.
,
Ming Zhou
,
Spectra Analysis Instruments, Inc.
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Excipients are pharmacologically inactive substances used as carrier and release controllers for active drug ingredients. A significant amount (30–80% solid) of polymeric excipients such as hydroxyl propyl cellulose (HPC), hydroxypropyl methyl cellulose (HPMC), hydroxypropyl methyl cellulose acetate succinate (HPMCAS), and povidone are used.
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UHPLC-UV Method for the Determination of Esomeprazole Using a Syncronis C18 1.7 ?m Column
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| By
Eilidh MacRitchie
,
Joanna Denbigh
,
Thermo Fisher Scientific
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This application note demonstrates the use of the Thermo Scientific Syncronis C18 1.7 ?m column for the determination of esomeprazole by UHPLC-UV.
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HPLC-UV Method for the Determination of Telmisartan Using a Core Enhanced Technology Accucore Column
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| By
Eilidh MacRitchie
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Thermo Fisher Scientific
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This application note demonstrates the use of the Thermo Scientific Accucore RP-MS column for the determination of telmisartan by HPLC-UV.
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Analytical Methods to Characterize and Quantify PEG and PEGylated Biopharmaceuticals
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| By
Christopher Crafts
,
Dave Thomas
,
Ian Acworth
,
Thermo Fisher Scientific
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Biotherapeutic peptides and proteins are often PEGylated (covalently bonded to polyethylene glycol polymers) to improve bioavailability, reduce immunogenicity, and extend circulating half-life (1). Achieving the desired properties for each application depends on optimizing the number and site of polymers attached, chain length, and the degree of chain branching.
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Detection of Protein Heterogeneity by HPLC
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| By
Atis Chakrabarti
,
Tosoh Bioscience LLC
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Protein heterogeneity is generated by post-translational modification, decomposition, and a variety of other processes, including chemical modification, denaturation, and aggregation. Since antibodies and recombinant proteins are now widely used for therapeutic treatment, it is essential to evaluate their heterogeneity during development, stability testing, and in the quality control of the final product.
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Maximizing HPLC Productivity with 2.5 μm Extended Performance (XP) Columns
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| By
Christopher J. Hudalla
,
Jane Xu
,
Kenneth J. Fountain
,
Waters Corporation
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The migration to chromatographic methods utilizing smaller particle sizes has been well demonstrated to increase productivity through faster, more efficient separations.
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Size-Exclusion Ultra Performance Liquid Chromatography Analysis of Insulin
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| By
Stephan Koza
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Paula Hong
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Kenneth J. Fountain
,
Waters Corporation
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Insulin was the first recombinant pharmaceutical produced. Currently, one of the critical quality control attributes of therapeutic insulin in the US and European Pharmacopoeia (USP and EP) monograph is the level of covalent high molecular weight (HMW) insulin as determined by HPLC size-exclusion chromatography.
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Novel Malaria Vaccine Candidates
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| By
Wyatt Technology Corp.
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Malaria remains one of the world's most deadly diseases, killing a child under five years of age every 30 s. Our branch aims to produce and characterize recombinant protein vaccines for Phase I and II human trials.
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Analysis of "Broad Spectrum" UVA and UVB Components in Sun Care Products for Compliance with New FDA Regulations
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| By
Nonie Danna
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PerkinElmer, Inc.
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The FDA has made changes to how products containing sunscreen are labeled in the U.S. to ensure they meet the new regulations set forth for safety and effectiveness. The new regulations will require companies that want to use the "broad spectrum" label to test for both UVA and UVB protection.
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Lenses or No Lenses? A Study of Ion Transfer Efficiency at Interfaces in a Lens-Free Triple Quadrupole MS
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| By
Felician Muntean
,
Roy Moeller
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Bruker Chemical and Applied Markets
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The efficiency of ion transfer between the quadrupole mass analyzers and the Q2 collision cell in a triple quadrupole mass spectrometry (MS) is critical for instrument robustness and sensitivity. Q2 is a radio frequency (RF) only non-mass filtering quadrupole containing only an inert collision gas such as Ar, He, or N2 to provide collision induced dissociation of the precursor ion selected in Q1.
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Effective Cleanup and Analysis of Metronidazole from Foaming Facial Cleanser
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| By
Seyed Sadjadi
,
Nicolas Leroy
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Sueki Leung
,
Erica Pike
,
Phenomenex, Inc.
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When working with complex matrices such as personal care products, sample preparation is perhaps the most difficult step of the analysis process. By utilizing a targeted sample preparation technique, such as ion-exchange SPE, analysis can be significantly improved as compared to less targeted techniques such as liquid-liquid extraction.
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Resistive Glass Inlet Tubes Increase Ion Throughput
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| By
Paula Holmes, PhD
,
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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Brittleback in Polyimide Coated Capillary Tubing
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| By
Joe Macomber
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Polymicro Technologies, A subsidiary of Molex Incorporated
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Polyimide coated fused silica capillary tubing is widely used in the separation sciences. In some instances a condition called brittleback can appear in the tubing. Its causes and remedies are discussed.
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Ascentis Express 5 micron: A Fused-Core Particle HPLC Column for Faster HPLC Separations with No Backpressure Concerns
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| By
Wayne K. Way
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Carmen T. Santasania
,
Supelco/Sigma-Aldrich
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Ascentis Express 5 micron columns provide a new choice for improving the performance of traditional HPLC systems. Based on Fused-Core particle technology, Ascentis Express provides the benefits of high speed and high efficiencies without the concerns of smaller particle columns. Due to the high efficiencies at low backpressures, Ascentis Express 5 micron can benefit conventional HPLC users with no drawbacks.
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