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The Benefits of Coupling Miniaturized Comprehensive 2D LC with Hybrid High-Resolution Mass SpectrometryComprehensive two-dimensional liquid chromatography (LC×LC) is evolving and becoming more commonly used in practice, but there are some specific problems still present that hamper the widespread use of this technology. One key aspect is the coupling of an on-line LC×LC system to a mass spectrometer. Generally, on-line LC×LC is based on a very fast second dimension separation to achieve low cycle times. This often results in flow rates that are far above the optimum for electrospray ionization mass spectrometry (ESI-MS). This month’s “Multidimensional Matters” looks at the benefits of miniaturization in the first and second dimension for coupling with a high-resolution mass spectrometer (HRMS) and describes an environmental analysis application.
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Dietary Supplements Method Modernization—A Review of Current Efforts to Modernize Compendial Methods and a Summary of Allowable AdjustmentsThe implementation of the FSMA (Food Safety Modernization Act) and the continued globalization of the food supply have increased the need for improved analytical methods for quality and safety testing. Food safety and quality requirements are increasingly stringent, as are consumer expectations. In addition to new methods, the industry continues to look for improvements in laboratory productivity and new ways to reduce costs. These trends extend to dietary supplements and natural products. This article discusses the current state of efforts to modernize US Pharmacopeia (USP) compendial methods to take advantage of new chromatography technology, including the use of “allowable adjustments”.
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Continuous Chromatographic Separation of Salt From Sugars by Simulated Moving Bed Technology (SMB) Using Orochem Zucchero ColumnsSimulated Moving Bed technology (SMB) is a continuous chromatography technique widely used in the pharmaceutical/biotechnology industry. The continuous chromatographic separation of sodium sulphate (Na2 SO4) from a mixture of glucose and mannose was established by using the Orochem Zuccheroâ„¢ columns and the SMB technology. The main advantages of SMB over batch chromatography includes better yields, higher purity, and decreased solvent usage, which together make the SMB technology economically viable and ideal for desalting applications.
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Branching Out: Mass Spectrometry and the Shape of BiotherapeuticsThose fond of puns point out that mass spectrometry (MS) has become ever more focused in the last two decades, while at the same time offering ever more information. The dynamic market for biotherapeutics has driven a number of developments, particularly following the paradigm of well-characterized biopharmaceutical products (WCBP) (1,2). Partly as a result of automation and interfacing, those trained in biological or biochemical disciplines now use mass spectrometers routinely. This also means that the sorts of questions asked of MS have changed. Coping with biomolecule heterogeneity is a key challenge, not generally an issue for small molecule drugs. The data complexity means that mass information alone is insufficient. And at the submission stage, regulators are increasingly concerned about tertiary structure and conformation, something that was not previously an analytical requirement (2). Adding polyethylene glycol (PEG) to already heterogeneous molecules to prolong their half-lives in the body raises..
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A Review of Column Developments for Supercritical Fluid ChromatographyThe authors review the requirements for columns specifically designed and manufactured for SFC.
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GCxGC-FID for Qualitative and Quantitative Analysis of PerfumesExploring the use of GCxGC-FID as a technique for qualitative and quantitative analysis of perfumes
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Development of Fully Automated Bubble-in-Drop Microextraction–Gas Chromatography–Mass Spectrometry of Organochlorine Pesticides in Environmental WatersIn this study, the intentional incorporation of an air bubble into a solvent droplet is proposed for fully automated bubble-in-drop microextraction–gas chromatography–mass spectrometric (BID-GC–MS) analysis of selected organochlorine pesticides as model analytes.
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Nontargeted Screening and Accurate Mass Confirmation of Pesticides Using High-Resolution LC–Orbital Trap Mass SpectrometryThe increasing use of pesticide testing coupled with reductions in maximum permissible residue levels of pesticides in food have driven demand for fast, sensitive, and cost-effective analytical methods for high-throughput screening of multiclass pesticides in food. Detection of 510 pesticides at low parts-per-billion levels can be achieved within minutes using orbital trap technology. The high resolving power of these systems enables accurate mass confirmation of all compounds, including isobaric pesticides. This article will provide an overview of current legislation and illustrate how mass spectrometry instrumentation can enable fast and accurate pesticide screening.
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Real-Time Profiling of Volatile Malt Aldehydes Using Selected Ion Flow Tube Mass SpectrometryThe authors use headspace SIFT-MS to target and identify volatiles in various malt aldehydes. The specificity and speed are compared to current methodology.
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Novel Analytical Methods for the Discovery and Trace Analysis of Biochemically Active CompoundsNovel analytical methods for the discovery and trace analysis of biochemically active compunds in three main area are described: protein analysis, screening technologies and multidimensional separations.
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Application of Microbore UHPLC–MS-MS to the Quantitation of In Vivo Pharmacokinetic Study SamplesLiquid chromatography coupled with tandem mass spectrometry (LC–MS-MS) is the primary bioanalytical technique used today within the pharmaceutical industry for the quantitation of small molecules in biological matrices such as plasma. In recent years, chromatographic resolution has been improved with the development of ultrahigh-pressure liquid chromatography (UHPLC) systems that utilize smaller diameter particles (< 3 μm) and operate at pressures > 5000 psi. While most LC systems utilized for this application are optimized for columns with internal diameters (i.d.) between 2.0 and 4.6 mm, a new UHPLC system designed for microbore columns (≤ 1 mm i.d.) has been introduced recently. This article will discuss the advantages of using a microbore UHPLC system coupled with a tandem mass spectrometer for the quantitation of in vivo pharmacokinetic samples. These advantages include reduced sample and solvent consumption, improved chromatographic resolution and speed, and reduced mass spectrometer source..
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Liquid Chromatography–Atmospheric Pressure Photoionization-Mass Spectrometry Analysis of the Nonvolatile Precursors of Rancid Smell in MayonnaiseFor lipid-containing food products like mayonnaise, determining nonvolatile lipid oxidation products, the precursor compounds for rancidity, makes it possible to predict product shelf life at an earlier stage in product development. A method based on normal-phase liquid chromatography with atmospheric pressure photoionization-mass spectrometry (LC–APPI-MS) was developed for this purpose.
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LC Analysis of Aminoglycoside Antibiotics Kanamycin and AmikacinKanamycin and amikacin are aminoglycoside antibiotics used to treat serious bacterial infections. Amikacin is used for infections resistant to other aminoglycosides because it is less susceptible to enzymatic reactions.
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High-throughput Method Development for Aldehydes and Ketones Using an Agilent 1290 Infinity LC-systemThis application note deals with the development of a fast method for the determination of 13 aldehyde and ketone derivates with the Agilent 1290 Infinity LC-system. The method, which used acetone as organic co-solvent, separates the analytes within 3.5 minutes.
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Extend uHPLC µm Column Lifetime with KrudKatcher Ultra In-line FiltersFor many years, the use of guard columns has been advocated by column manufacturers and other experts to protect and extend column lifetime and performance of analytical columns from potential damage caused by the presence of chemical contaminants and microparticulates in the sample and mobile phase.
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UHPLC Coupled with Fourier Transform Orbitrap for Residue AnalysisThe trend in residue analysis has changed from target-oriented procedures towards accurate mass full-scan MS techniques. This article describes these developments and addresses the implications of 2002/657/EC.
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UHPLC Coupled with Fourier Transform Orbitrap for Residue AnalysisThe trend in residue analysis has changed from target-oriented procedures towards accurate mass full-scan MS techniques. This article describes these developments and addresses the implications of 2002/657/EC.
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Determination of Methacholine Chloride and Potential Impurities Using a Reagent-free Ion Chromatography SystemMethacholine chloride is a synthetic analogue of the neurotransmitter acetylcholine used to assess bronchial asthma of subjects in respiratory function labs and epidemiological field studies.
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The Unique Selectivity of π-Interactions for Solid-Phase ExtractionHypercrosslinked polystyrene-type (solid-phase extraction) SPE materials exhibit a unique ability to enter p-interactions with aromatic, heterocyclic and unsaturated compounds. This property permits selective extraction and pre-concentration of the above classes of species from non-polar media and fatty matrices. The principle has been exploited for developing analytical protocols to determine polar furan derivatives in mineral transformer oil, polyaromatic hydrocarbons (PAHs) in smoked fish and for the fractionation of polychlorinated aromatic compounds in environmental matrices.
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Data Handling and Validation in Automated Detection of Food Toxicants Using Full Scan GC–MS and LC–MSAn overview of current chromatography-based food toxicant screening is presented.
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A Review of Column Developments for Supercritical Fluid ChromatographyThe authors review the requirements for columns specifically designed and manufactured for SFC.
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LC–MS-MS-Based Strategies for the Targeted and Nontargeted Screening of Contaminants in Food, Environmental, and Forensic SamplesLiquid chromatography coupled to mass spectrometry (LC–MS) using electrospray ionization (ESI) is a powerful analytical tool for the analysis of a wide molecular weight range of polar, semivolatile, and thermally labile compounds.
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Investigating Solvent Purity Using Comprehensive Gas Chromatography: A Study of AcetonesInvestigating Solvent Purity Using Comprehensive Gas Chromatography: A Study of Acetones
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Conquering Compliance: Robust Testing Solutions for Metals & PFAS in WaterWebinar Date/Time: Tue, Oct 8, 2024 10:00 AM EDT (4:00 PM CET)
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A Comparative Study on the Purification of Library Compounds in Drug Discovery Using Mass-Directed Preparative SFC and Preparative RPLCIn the past decade, supercritical fluid chromatography (SFC) has experienced a steady growth in acceptance, particularly in pharmaceutical and chemical laboratories. In SFC, "supercritical" CO2 combined with one or more polar organic solvents, most commonly alcohols, are used as mobile phase. Preparative SFC is deemed by many to hold the greatest promise to attain mainstream acceptance. The reduction in solvent consumption and collection in relatively small volumes of volatile organic solvents, hence, a much less stringent post-purification endeavour, lead to significant savings on operation costs. For example, Ripka et al. calculated that 20000 samples purified by SFC instead of reverse phase liquid chromatography (RPLC) would realize a 48 times reduction in solvent consumption.1
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Rapid LC Determination of UV Filters in Cosmetics using Ethanol as the Mobile PhaseA rapid and environmentally friendly LC method for the simultaneous determination of 12 UV filters in cosmetic samples using ethanol as the mobile phase.
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Resistive Glass Inlet Tubes Increase Ion ThroughputResistive 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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Fast Screening and Quantification of Pesticides Using an LC-MS Solution – The Pesticides Explorer CollectionA fully tested LC-MS/MS workflow for rapid and robust quantification of more than 250 pesticides below maximum residue limits (MRLs) with sensitivity, accuracy, and precision that meets stringent EU guidelines.
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Improving the Analytical Workflow for Protein Biopharmaceutical Characterization with a Novel LC–MS System SolutionThe ability to characterize protein therapeutics throughout the product development cycle is discussed.
