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Improvement of GC Sensitivity for Polar and Nonpolar PAHs by Using a Deactivated LinerThis article presents the findings from an analysis conducted on sensitivity in GC on the basis of the complex group of polycyclic aromatic hydrocarbons and PAH derivatives.
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Meeting Analytical Demands for Biopharmaceuticals with Mass Spectrometry in Late Development, Manufacturing, and Quality ControlMass spectrometry (MS) is emerging as a critical tool in biopharmaceutical late stage development, manufacturing, and quality control (QC) environments. The rapid growth of biologics in development, the increasing demand for more robust analytical technologies to directly monitor the critical quality attributes (CQAs) of these new drugs, and longer term industry initiatives aimed at improving quality and productivity, such as quality by design (QbD) regulatory submissions and continuous manufacturing, are all fueling a greater need for mass monitoring with MS.
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Identifying Packaging-Related Drug Product ImpuritiesThis 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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Identification of a Low-Abundant Biomarker in Human Serum Using nanoLC–LIT-TOF MS and Information-Based Acquisition TechniquesSerum protein profiling using mass spectrometry (MS) is one of the most promising approaches for biomarker identification.
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Multimodal HPLC Screening of Polysaccharide-based Chiral Stationary PhasesHigh-performance liquid chromatography (HPLC) is a powerful tool for the enantioselective separation of chiral drugs. However, the selection of an appropriate chiral stationary phase (CSP) and suitable operating conditions is a bottleneck in method development and a time- and resource-consuming task. Multimodal screening of a small number of CSPs with broad enantiorecognition abilities has been recognized as the best strategy to achieve rapid and reliable separations of chiral compounds. This paper describes the generic screening strategy developed at Johnson & Johnson Pharmaceutical Research and Development (J&J PRD) to successfully develop enantioselective HPLC methods for chiral molecules of pharmaceutical interest.
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Multimodal HPLC Screening of Polysaccharide-based Chiral Stationary PhasesHigh-performance liquid chromatography (HPLC) is a powerful tool for the enantioselective separation of chiral drugs. However, the selection of an appropriate chiral stationary phase (CSP) and suitable operating conditions is a bottleneck in method development and a time- and resource-consuming task. Multimodal screening of a small number of CSPs with broad enantiorecognition abilities has been recognized as the best strategy to achieve rapid and reliable separations of chiral compounds. This paper describes the generic screening strategy developed at Johnson & Johnson Pharmaceutical Research and Development (J&J PRD) to successfully develop enantioselective HPLC methods for chiral molecules of pharmaceutical interest.
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Molecular Interaction Sensors: A New Type of Detector for Separation MethodsPotentiometry is a new detection method for liquid chromatography (LC) and capillary electrophoresis (CE). The principle behind this method is familiar to chromatographers because the signals depend on the partitioning tendency of analytes over the sensor coating and the eluent. This partitioning provokes a change in the surface potential and the detection of these changes can be classified as "potentiometric". A conversion algorithm is needed to convert the generated signals to concentration-related tracings (chromatograms).
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CE–MS-MS for the Identification of Chemical Warfare Agent Degradation ProductsWith the threat of terrorism growing, the development of analytical techniques for the detection and identification of chemical warfare agent defradation products has increased. Capillary electrophoresis (CE) presents interesting features for this application.
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FT–MS to Provide Novel Insight into Complex SamplesMore than 20 years passed after the introduction of Fourier transform–ion cyclotron resonance mass spectrometry (FT-MS) before advancements in electronics and computer technology enabled the development of practical, high-performance instruments. Modern analytical FT-MS instruments rely on sophisticated electronic circuitry and powerful computer software to achieve the dramatic resolving power and mass accuracy typical for the instrumentation. Here, the power of modern hybrid FT-MS instrumentation is discussed by demonstrating the capability of this instrumentation for selected applications such as the analysis of crude oil, intact protein, and fragile noncovalent complex samples.
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Quantitation-Enhanced Data-Dependent (QED) Scanning of Drinking Water Samples Using EQuan for Pesticide AnalysisThis application note describes an LC–MS–MS method for on-line sample preparation and concentration of drinking water samples prior to analysis using a triple quadrupole with full scan Q3 confirmation.
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Key LC–MS Techniques Benefit Life Sciences ResearchersState-of-the-art mass spectrometry (MS) techniques of growing importance to life sciences research now include not just liquid chromatography (LC)–MSn (n = 2–11), but also LC–matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF), LC-MALDI-TOF-TOF, electrospray ionization (ESI)-TOF, and LC-Fourier transform (FT) MS.
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Identification of a Low-Abundant Biomarker in Human Serum Using nanoLC–LIT-TOF MS and Information-Based Acquisition TechniquesSerum protein profiling using mass spectrometry (MS) is one of the most promising approaches for biomarker identification.
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Routine Switching between High and Low pH on Xbridge HPLC ColumnsThe effect of switching between high and low pH mobile phases on a single analytical HPLC column was investigated. The ability to rapidly switch between pH extremes on XBridge columns without special washing/re-equilibration steps dramatically reduces the time for separation of pharmaceutical compounds.
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The Challenges of Changing Retention Times in GC–MSReproducing analysis conditions is crucial to achieving consistent, accurate results in gas chromatography–mass spectrometry (GC–MS). Valid reproduction demands appropriate application of technique, solid method design, reliable and accurate equipment, and a dedicated team of well-practiced technicians and researchers. But even when all these conditions are met, users can be held back by the more subtle elements in GC–MS operations, such as cutting or changing a column, or setting up the same experiment on different equipment. Even getting the parameters of a test organized so that it can be reproduced elsewhere - in a laboratory across the hall, the country, or the world - can be daunting. Consistent GC–MS results depend upon retention-time reproducibility.
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An Expanding Role: The Use of Ultrahigh Performance LC–TOF-MS, GC–TOF-MS, Accurate Mass, and Isotope Modeling for Screening Complex MixturesUltrahigh performance liquid chromatography (LC)–time-of-flight mass spectrometry –(TOF-MS) and gas chromatography (GC)–TOF-MS are powerful approaches for screening target compounds and identifying or characterizing nontarget compounds in complex mixtures. The combination of accurate mass data and newly developed software enables truly generic screening methods with TOF-MS, and the confident detection, identification, and confirmation of small molecules in a range of application areas.
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Removal and Depletion of High-Abundance Proteins from Biological FluidsThis installment of "Sample Prep Perspectives" discusses techniques for the reduction/depletion of high-abundance proteins.
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Investigation of Transferrin Structure via Novel Electron Capture Dissociation Techniques Using a Hybrid Linear Ion Trap Time-of-Flight Mass SpectrometerProtein and peptide analysis via tandem mass spectrometry (MS-MS) has resulted in a wealth of information regarding protein identification, structure, and abundance levels over the past 10 years. Techniques such as neutral loss scanning and collision-induced dissociation (CID) have been especially helpful in facilitating the identification of a multitude of previously unknown sites of protein phosphorylation. However, many of the techniques used to obtain this information are labor intensive and work inconsistently. To address this problem, much effort has been put forth to find alternative methods of fragmenting peptides and proteins that are less difficult and applicable to a wide gamut of peptide classes. Examples of recently developed dissociation techniques include infrared multiphoton dissociation (IRMPD) and electron transfer dissociation (ETD). The implementation of these new techniques has widened the spectrum of peptides amenable to tandem mass spectral analysis.
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FAIMS Removes Chemical Background and Interference from the Analysis of Linoleic Acid in Cancer Cell ExtractsAssay sensitivity is the lowest concentration at which a targeted analyte can be measured and is often limited by chemical background or co-eluting interferences. FAIMS in combination with liquid chromatography (LC) and zero neutral loss tandem MS was used to remove chemical background and co-eluting interferences from the analysis of linoleic acid in cancer cell extracts. Concentration of endogenous linoleic acid was determined from back-calculation of standard calibration samples fortified with deuterium-labeled linoleic acid. No internal standard was used. LC–MS-MS analysis of the cancer cell extracts resulted in an increase in signal-to-noise ratio of 10-fold. The assay sensitivity was increased 10 times over the traditional LC–MS-MS experiment exclusively due to the new FAIMS technology.
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Mass Spectrometry Advances Translational Medicine Trends in Proteomic and Small-Molecule ApplicationsEnabling targeted quantitative proteomics applications and hypothesis-driven inquiries will help researchers to understand how proteins function in living systems. The discovery and validation of small molecule and protein-based biomarkers, and the eventual translation of these discoveries from the research lab to the clinic, involves robust mass spectrometry (MS) systems and software that make it easier for technicians to perform routine sample analyses on liquid chromatography (LC)–MS-MS systems, which continue to be used in an increasing number of both protein and small molecule analysis applications.
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Ionization RevisitedElectrospray ionization (ESI), atmospheric pressure chemical ionization (APCI) and atmospheric pressure photoionization (APPI) are now among the most commonly used techniques for creating ions, especially from small-molecule compounds in solution. They have become so familiar that now many articles only refer to them briefly. Yet each technique has dramatic predictive strength on the outcome and limits of an analysis.
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A New Tool for Mass Analysis of Unknown Molecules: High-Resolution Multistep Tandem MS with Wide Dynamic Range Quantitative AnalysisMass spectrometers are effective for identifying and quantifying unknown molecules, such as disease-related proteins and small molecules in pharmaceutical research and medical diagnosis. In addition, mass spectrometry (MS) can be particularly powerful when analyzing molecules with complex structures, such as posttranslationally modified proteins. Among various MS approaches, high-resolution multistep tandem MS (MS-MS) is an emerging methodology for accurate identification of complex molecules. In this article, we describe a new approach for mass analysis with enhanced quantitative capability combined with high-resolution multistep MS-MS, where the dynamic range of quantitation covers four orders of magnitude.
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Multimodal HPLC Screening of Polysaccharide-based Chiral Stationary PhasesHigh-performance liquid chromatography (HPLC) is a powerful tool for the enantioselective separation of chiral drugs. However, the selection of an appropriate chiral stationary phase (CSP) and suitable operating conditions is a bottleneck in method development and a time- and resource-consuming task. Multimodal screening of a small number of CSPs with broad enantiorecognition abilities has been recognized as the best strategy to achieve rapid and reliable separations of chiral compounds. This paper describes the generic screening strategy developed at Johnson & Johnson Pharmaceutical Research and Development (J&J PRD) to successfully develop enantioselective HPLC methods for chiral molecules of pharmaceutical interest.
Latest:
Key LC–MS Techniques Benefit Life Sciences ResearchersState-of-the-art mass spectrometry (MS) techniques of growing importance to life sciences research now include not just liquid chromatography (LC)–MSn (n = 2–11), but also LC–matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF), LC-MALDI-TOF-TOF, electrospray ionization (ESI)-TOF, and LC-Fourier transform (FT) MS.
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Gas Chromatography-Time-of-Flight Mass Spectrometry in Food AnalysisGas chromatography (GC) coupled to time-of-flight mass spectrometry (TOF-MS) offers unique solutions for various analytical applications including the analysis of food quality, authenticity and safety markers. This article provides a general overview of TOF-MS basic features, highlighting its advantages and limitations compared with GC conventional mass analyzers. Examples of recent results obtained selected food contaminants and flavor components are described illustrate the potential of this recently introduced technique.
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Supercritical Fluid Chromatography (SFC): A Review of Technical DevelopmentsIn the mid 1980s the chromatographic application of gases compressed (or liquefied) to supercritical state was tested by research teams from several analytical instrument manufacturers. The recently introduced capillary columns seemed ideal candidates on which to perform such supercritical fluid chromatography (SFC) methods.
Latest:
Mass Spectrometry Advances Translational Medicine Trends in Proteomic and Small-Molecule ApplicationsEnabling targeted quantitative proteomics applications and hypothesis-driven inquiries will help researchers to understand how proteins function in living systems. The discovery and validation of small molecule and protein-based biomarkers, and the eventual translation of these discoveries from the research lab to the clinic, involves robust mass spectrometry (MS) systems and software that make it easier for technicians to perform routine sample analyses on liquid chromatography (LC)–MS-MS systems, which continue to be used in an increasing number of both protein and small molecule analysis applications.
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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.
Latest:
Identification of a Low-Abundant Biomarker in Human Serum Using nanoLC–LIT-TOF MS and Information-Based Acquisition TechniquesSerum protein profiling using mass spectrometry (MS) is one of the most promising approaches for biomarker identification.
Latest:
CE–MS-MS for the Identification of Chemical Warfare Agent Degradation ProductsWith the threat of terrorism growing, the development of analytical techniques for the detection and identification of chemical warfare agent defradation products has increased. Capillary electrophoresis (CE) presents interesting features for this application.
