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*** TEST *** Estimation of the Main Sources of Uncertainty in Chromatographic Analysis: Determination of Biogenic Amines ***TEST ***This article establishes the estimation of the uncertainty associated with the chromatographic determination of biogenic amines. The authors identify and estimate each source of uncertainty to establish the accuracy of results and to obtain a better understanding of the method. Thus, measurement uncertainty was split into two sections: uncertainty related to the working conditions, which considers the equipment used, and inherent uncertainty, which includes the chemical stages indicated in the procedure as well as calibration sources, taking into account the existence of the matrix effect. Recovery studies also were made to quantify the contribution of bias to the overall uncertainty. This parameter was calculated for the determination of biogenic amines in different types of samples.
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Characterization of Hyaluronic Acid with On-Line Differential Viscometry, Multiangle Light Scattering, and Differential RefractometryHyaluronic acid (HA) is a naturally occurring, unbranched polysaccharide that consists of alternately repeating D-glucuronic acid and N-acetylglucosamine units. This biopolymer is present throughout all mammalian systems but occurs primarily in synovial (joint) fluid, vitreous humor, and various loose connective tissues (such as rooster comb) (1). HA is of enormous commercial interest for ophthalmic, medical, pharmacological, and cosmetic applications.
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Prevention is Better Than Cure: An Alternative Approach in Sample Preparation of Complex SamplesCombining a membrane with a solid sorbent can improve selectivity and save time in sample preparation.
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Vitamin Analysis by Capillary ElectrophoresisThis article discusses the role of CE for vitamin analysis and highlights a number of practical applications.
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When Ideal Isn't PracticalSometimes you must sacrifice chromatographic performance to obtain analytical results.
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Enhanced Stability Stationary Phases for HPLCThis article presents an overview of high performance liquid chromatography stationary phases with enhanced stability at high pH, focusing on the methods by which they were prepared. Among the many alternatives, the authors introduce reversed phases based upon metallized silica supports that show superior performance during stability testing at high pH, when compared with conventional C18 phases based upon bare silica.
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*** TEST *** Estimation of the Main Sources of Uncertainty in Chromatographic Analysis: Determination of Biogenic Amines ***TEST ***This article establishes the estimation of the uncertainty associated with the chromatographic determination of biogenic amines. The authors identify and estimate each source of uncertainty to establish the accuracy of results and to obtain a better understanding of the method. Thus, measurement uncertainty was split into two sections: uncertainty related to the working conditions, which considers the equipment used, and inherent uncertainty, which includes the chemical stages indicated in the procedure as well as calibration sources, taking into account the existence of the matrix effect. Recovery studies also were made to quantify the contribution of bias to the overall uncertainty. This parameter was calculated for the determination of biogenic amines in different types of samples.
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How to Take Maximum Advantage of Column-Type SelectivityHow do non-alkylsilica columns provide us an additional dimension of column selectivity?
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Identifying Compounds Despite Chromatography Limitations: Organophosphates in Treated SewageThe authors descrive the use of GC–MS to isolate and identify potentially toxic compounds in concentrated extracts of sewage treatment plant effluents.
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Ion Mobility Spectrometry (IMS): How It Works and Its Use in BiotechnologyIMS is a valuable tool for biopharmaceutical analysis. Two formats in particular have proven useful: cyclic IMS and structures for lossless manipulations (SLIM).
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A Protocol for High-Throughput Drug Mixture Quantitation: Fast LC–MS of Flow Injection Analysis–MSThe authors compare fast LC}MS with a flow injection analysis}MS method for effective quantitation in the high-throughput environment of today's drug discovery laboratories.
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Misconduct in Research – An Eastern Analytical Symposium Interview with Dr. Elisabeth Bik, Part 6LCGC spoke with Elisabeth Bik, PhD, of Harbers Bik LLC about the challenge of preventing scientific and research misconduct in scientific publishing. This segment is Part 6 of 6 and concludes our conversation with Bik.
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Glycoprotein Monosaccharide Analysis Using HPAE-PAD with Eluent GenerationGlycoprotein monosaccharide compositional analysis is important for the development and manufacture of glycoprotein human therapeutics. Here we report a robust method for this analysis. This chromatographic method requires no mobile phase preparation thus saving time and delivering excellent retention time reproducibility that results in good method reproducibility.
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Analysis of Dioxins in Foods and Feeds Using Gas Chromatography Tandem Mass SpectrometryIn the early days of dioxin analysis, applied methods were laboratory- and time-consuming. Only GC–HRMS, which is complicated, was used. Nowadays, GC–MS/MS is suitable for control proposes. Using GC–MS/MS means that solvent consumption for sample preparation can be reduced by a factor of 10 and the purity of the obtained fraction can be enhanced, indicating that GC–MS/MS is appropriate for dioxin analysis.
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Determination of Geosmin in Water Samples Using Person-Portable GC–MS and Sample Preparation InstrumentsTorion Technologies Inc.
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*** TEST *** Estimation of the Main Sources of Uncertainty in Chromatographic Analysis: Determination of Biogenic Amines ***TEST ***This article establishes the estimation of the uncertainty associated with the chromatographic determination of biogenic amines. The authors identify and estimate each source of uncertainty to establish the accuracy of results and to obtain a better understanding of the method. Thus, measurement uncertainty was split into two sections: uncertainty related to the working conditions, which considers the equipment used, and inherent uncertainty, which includes the chemical stages indicated in the procedure as well as calibration sources, taking into account the existence of the matrix effect. Recovery studies also were made to quantify the contribution of bias to the overall uncertainty. This parameter was calculated for the determination of biogenic amines in different types of samples.
Latest:
Characterization of Hyaluronic Acid with On-Line Differential Viscometry, Multiangle Light Scattering, and Differential RefractometryHyaluronic acid (HA) is a naturally occurring, unbranched polysaccharide that consists of alternately repeating D-glucuronic acid and N-acetylglucosamine units. This biopolymer is present throughout all mammalian systems but occurs primarily in synovial (joint) fluid, vitreous humor, and various loose connective tissues (such as rooster comb) (1). HA is of enormous commercial interest for ophthalmic, medical, pharmacological, and cosmetic applications.
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Developments in Field‑Flow Fractionation Coupled to Light ScatteringField-flow fractionation (FFF) coupled to light scattering is a powerful method to separate and characterize nanoparticles, proteins, and polymers from a few nanometres to a few micrometres. The technique is one of the few that can cover the full size range of nanomaterials and provide high-resolution size distributions and additional characterization. New developments in FFF enhance performance and productivity.
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Nontargeted, Discovery-Based Profiling of the Yeast Metabolome Using QTOF LC–MS and LC–MS-MSA discovery-based, untargeted metabolomics analysis of hundreds of yeast metabolites under robust, controlled extraction conditions followed by identification is described.
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High-Throughput Tools and Approaches for Development of Process Chromatography StepsAn overview of high-throughput process development (HTPD) tools and approaches, as well as a case study
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Novel C18 Stationary Phase Provides Exceptional Results for Metabolite ProfilingMetabolomics, the study of small molecule metabolites that are found within a biological sample, is an emerging field of study. Progress in this field depends upon technological advancement in the fields of LC–MS and separation technology.
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Matrix-Assisted Laser Desorption-Ionization Imaging Mass Spectrometry for Direct Tissue AnalysisA summary of the most recent advances in sample preparation, instrumentation, and data-processing techniques for MALDI-IMS
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Matrix-Assisted Laser Desorption-Ionization Imaging Mass Spectrometry for Direct Tissue AnalysisA summary of the most recent advances in sample preparation, instrumentation, and data-processing techniques for MALDI-IMS
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Matrix-Assisted Laser Desorption-Ionization Imaging Mass Spectrometry for Direct Tissue AnalysisA summary of the most recent advances in sample preparation, instrumentation, and data-processing techniques for MALDI-IMS
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Trace Metabolic Profiling and Pathway Analysis of Clomazone Using LC–MS-MS and High Resolution MSDetection, 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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Time-Resolved SRM Analysis and Highly Multiplexed LC–MS-MS for Quantifying Tryptically Digested ProteinsThe inclusion of time-resolved selected reaction monitoring (SRM) functionalities into mass spectrometer control software allows large numbers of peptides to be quantified using short LC–MS-MS methods.
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Determination of Explosives Using Fast and High Resolution Liquid Chromatography with the Agilent 1290 Infinity LC SystemThis application note describes the method for detection of nanogram levels of explosive constituents in seawater samples (e.g., after detonation of unexploded ordnance devices). The improved chromatographic method was developed using the Agilent 1290 Infinity LC Method Development system.
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Analysis of Amphetamines and Synthetic Cathinones in Hair Samples Using LC–Tandem Mass Spectrometry and Solid-Phase ExtractionAn efficient method for forensic analysis of amphetamines and synthetic cathinones - the illicit drugs often called "bath salts" - in hair samples.
