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Hardware and Software Challenges for the Near Future: Structure Elucidation Concepts via Hyphenated Chromatographic TechniquesThis month, guest columnists Kind and Fiehn discuss small-molecule structure elucidation (excluding peptides) using hyphenated chromatographic techniques, mass spectrometers, and other spectroscopic detectors.
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Challenges in Small-Molecule Quantitation by Mass SpectrometryDrug discovery scientists are continually striving to improve productivity and efficiency in their workflows. From early discovery to clinical development, existing workflow bottlenecks represent an opportunity to develop solutions to speed the process and improve productivity. The key requirements for quantitative analysis are precision, accuracy, and linear dynamic range. With any quantitative instrument, the hope is that it will be applicable to a vast range of coumpounds, ruggest, and fast. New mass spectrometry (MS) technologies are being developed that meet these criteria and permit high throughput while enabling its application to areas in which speed limitations previously curtailed its practicality. In particular, in the area of ADME profiling, new MS platforms are becoming available that increase the throughput by at least 25-fold, by combining the speed of matrix-assisted laser desorption ionization (MALDI) with the specificity of triple-quadrupole MS. This is bound to greatly accelerate the ADME..
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Quantifying an Anthrax LF Inhibitor in Human Plasma by HPLC-MS-MSThis article describes the method development and performance characteristics of the validated LFI assay and evaluates stability in human plasma.
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Shape Selectivity in Reversed-Phase Liquid ChromatographyA 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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Speeding Up Pharmaceutical UHPLC Method Development with an Integrated, Ultrafast, Automated Method Scouting SolutionIn HPLC method development, screening of various para-meters such as stationary phase, eluents, and temperatures is conducted to find optimal resolution. However, method development can be a time consuming and inefficient process. UHPLC technology can be applied to significantly shorten both the analysis and development times. Here we describe an integrated and ultrafast automated method scouting solution that provides fast and efficient method development processes.
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Accelerated Discovery and Quantitation of Lipids in Complex ExtractsThe authors discuss analytical methods for lipidomics.
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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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In Vino Veritas: LC–MS in Wine AnalysisLiquid chromatography–mass spectrometry (LC–MS) is a popular technique for the analysis of wine. This article gives an overview of wine analysis and new insights this technique has revealed regarding the composition of wine, possible health benefits, customer safety and the understanding of winemaking processes.
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Maximize Mass Spectrometry Through SoftwareIncreases in the speed and sensitivity of MS systems have set new standards in quantitative and qualitative analysis.
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Review and Optimization of Linearity and Precision in Quantitative HPLC–ELSD with ChemometricsHPLC with ELSD continues to grow in popularity as a "quasi- universal" detector. Improvements in ELSD instrument design, including low temperature evaporation, have recently been commercialized...
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Maximizing HPLC Productivity with 2.5 μm Extended Performance (XP) ColumnsThe migration to chromatographic methods utilizing smaller particle sizes has been well demonstrated to increase productivity through faster, more efficient separations.
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Why Use Signal-To-Noise As a Measure of MS Performance When It Is Often Meaningless?Signal-to-noise of a chromatographic peak from a single measurement has been used determine the performance of two different MS systems, but this parameter can no longer be universally applied and often fails to provide meaningful estimates of the instrument detection limits (IDL).
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Case Studies: Improved Productivity with Fast GC AccessoriesThermal agility is a term that describes the ability of an oven to heat up and cool down. Both steps comprise the complete cycle time which, in turn, determines sample throughput. Fast GC accessories provide an attractive means of increasing sample throughput because they are easy to implement and deliver reliable performance at low cost. They require little or no bench space and do not incur additional costs for consumables and support equipment such as autosamplers, data acquisition software, and computers. Fast oven cooling is especially attractive because methods do not have to be re-validated since the separation parameters remain unchanged.
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Reversed-Phase Enantioselective Chromatography with New µ-mm Chiral Stationary PhasesTo meet the growing need for fast reversed-phase enantiomer separations, two new 3-μm reversed-phase columns, CHIRALCEL® OD® -3R and CHIRALPAK® AD® -3R, have been introduced. High column performance and column stability under a wide range of conditions, including aqueous solvent systems suited to LC–MS, have been
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Use of Electron Capture Negative Ion Mass Spectra to Establish the Identities of Polybrominated Diphenyl Ether Flame Retardants and Their Degradation ProductsDetrimental health effects of a group of brominated flame retardants, polybrominated diphenyl ethers (PBDEs), have been recognized recently, but only after their wide usage and consequently, global dispersal. Of the possible 209 PBDE congeners, 39 (varying in degree of bromination from mono to deca) have been identified previously in the three common technical mixtures. Additional congeners, presumably debromination products of the fully brominated decabromodiphenyl ether (BDE-209), also have been reported in biotic and abiotic environments. However, costly analytical standards are needed to confirm their identification. In addition, the most widely used identification approach, electron ionization (EI) mass spectrometry (MS), primarily produces spectra indicating only homologue grouping (for example, hepta-BDE). Without specific compound identification, full assessment of toxicological consequences of PBDE burdens is impeded. It has been reported previously that electron-capture negative ionization (ECNI),..
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Approaches to Singleton Achiral Purification of Difficult Samples for Discovery Research SupportSeveral approaches for purifying difficult samples more efficiently for discovery research support are mentioned in this paper. These approaches use mass triggered HPLC on various specialty columns.
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Detection of Doping Agents by LC–MS and LC–MS-MSIn the last decade, research on the detection of all groups of doping agents has been investigated by LC-MS, and routine LC-MS screening applications are now available for almost all classes of doping agents.
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Dynamic Extraction: A High-Speed, High-Capacity Purification Process That is Rapidly ScalableThe authors discuss a preparative process using the principles of countercurrent chromatography. This process is faster, capable of loadings from milligrams to hundreds of grams, and uses robust equipment.
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Simultaneous Measurement of an API with its Counter-ion Using Corona CAD with HPLC-HILICThe analysis of anions and cations is critical during drug development and related QC. Measure both the API and the counterion in a single run.
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Determination and Quantification of Primary Aromatic Amine in Printer InkKnauer Application Note
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Ion Suppression: A Major Concern in Mass SpectrometryIn this tutorial, the mechanism and origin of ion suppression will be investigated, as well as ways to validate the presence, and circumvent or compensate for, the effects in LC-MS.
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Agilent J&W Ultra Inert GC Columns: A New Tool to Battle Challenging Active AnalytesQC test probes serve a vital function in ensuring the reproducibility of modern GC columns. These probes ensure that the columns have been properly deactivated, contain the correct amount of stationary phase, and have the same relative retention as the last column purchased. The choice of individual compounds in these test mixes varies widely and can have profound consequences on the performance of a column in the users' applications.
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The Use of Subtle Differences in Selectivity to Improve Separation of Structurally Diverse AnalytesThe separation of structurally diverse analytes is often complicated by chance coelutions with other analytes or with matrix related compounds. Often the column is blamed, but while such coelutions make analysis difficult they do not necessarily indicate a faulty column, poor chromatography or method design.
