Author
Latest:
Lab-on-a-Chip GC for Environmental ResearchThe development of a microfabricated comprehensive GC that can be used as a portable measurement device.
Latest:
Separation Science in Drug Development, Part 4: Quality ControlThis fourth and last instalment in the “Separation Science in Drug Development” series provides an overview of modern practices of quality control in small-molecule drug development, including activities such as setting specifications, method validation and transfer, release and stability testing, and authoring chemistry, manufacturing, and controls (CMC) sections of regulatory filings.
Latest:
Meeting the Challenges of Bioanalysis with Time-of-Flight High Resolution Mass Spectrometry (TOF-HRMS)In an era where “more data in less time” is expected, bioanalytical scientists have had to become more resourceful. Consequently, bioanalytical laboratories are adopting and extending the use of high-resolution mass spectrometry (HRMS) and, in particular, time-of-flight high-resolution mass spectrometry (TOF-HRMS). One of the key benefits of TOF-HRMS is consistent resolution, sensitivity, and mass accuracy - even at high scan speeds with large molecules being analyzed.
Latest:
Analysis of Proteins, Biologics, and Nanoparticles in Biological Fluids Using Asymmetrical Flow Field-Flow FractionationAspects of applying AF4 to plasma, serum, milk, and cerebrospinal fluid in the field of analysis and characterization of proteins, biologics, and nanoparticles in biological fluids are reviewed.
Latest:
Practical Applications of Asymmetrical Flow Field-Flow Fractionation: A ReviewThis review highlights applications for which AF4 is particularly well suited, and explains when not to use the technique.
Latest:
The Rise of Hydrophilic Interaction Chromatography (HILIC)Hydrophilic interaction chromatography (HILIC) is becoming more popular. Dr Tohru Ikegami from the Department of Biomolecular Engineering at the Kyoto Institute of Technology in Kyoto, Japan, reveals more about the evolution of HILIC, important new developments, and tips on how to get the most from this technique.
Latest:
Determination and Quantification of Primary Aromatic Amine in Printer InkKnauer Application Note
Latest:
Maximization of Selectivity in Reversed-Phase Liquid Chromatographic Method Development StrategiesThe approach described here will help chromatographers produce highly efficient method development strategies for reversed-phase LC separations in a relatively short time frame.
Latest:
Maximization of Selectivity in Reversed-Phase Liquid Chromatographic Method Development StrategiesThe approach described here will help chromatographers produce highly efficient method development strategies for reversed-phase LC separations in a relatively short time frame.
Latest:
Low-Level Determination of Mutagenic Nitrosamine Impurities in Drug Substances by LC–MS/MSThis article discusses the development of a series of applications that will allow for the determination of a number of nitrosamines that have been identified by the FDA as genotoxins to monitor, initially showing how to perform a separation of these compounds from the API and then looking at how MS can be applied to the analysis to ensure that the required detection limits can be reached.
Latest:
An Assessment of Stationary Phase Selectivity in SFCSustainability concerns are renewing interest in SFC, often as a substitute for HPLC. With the broader application of SFC, we need a better understanding of selectivity in SFC, where stationary phase classification is not well established. This study assessed and measured the selectivity differences afforded by three prototype SFC phases.
Latest:
Consolidated GC-MS/MS Analysis of OCPs, PAHs, and PCBs in Environmental SamplesAnalysis of OCPs, PAHs and PCBs in environmental samples through a consolidated GC-MS/MS method using the Thermo Scientific™ TRACE™ 1310 GC and the TSQ™ 8000 triple quadrupole GC-MS/MS.
Latest:
Professor Michel DreuxIt is with great sadness we announce the death of Professor Michel Dreux. Professor Dreux was a professor at the University of Orléans, France.
Latest:
Ultrahigh-Pressure Size-Exclusion Separations of Engineering Plastics: Challenges and OpportunitiesUltrahigh-pressure size-exclusion chromatography (UHPSEC) can potentially offer a new direction and overcome some of the disadvantages (for example, limited resolution and long analysis time) associated with conventional SEC analysis. UHPSEC is based on using sub-3-µm silica-organic hybrid particles under elevated pressures (often above 400 bar) to improve the separation efficiency and increase analysis speed. In spite of the benefits promised by the chromatographic theory, there are some uncertainties that may limit the proliferation of UHPSEC in polymer analysis. As a result of possible issues associated with the use of a different stationary phase - including secondary interactions and polymer degradation - it is unclear whether UHPSEC will provide results comparable to those of traditional SEC methods. In this article, the advantages and challenges of UHPSEC for the analysis of different engineering thermoplastics are discussed, as well as a comparison of results obtained with UHPSEC and conventional SEC.
Latest:
Ultrahigh-Pressure Size-Exclusion Separations of Engineering Plastics: Challenges and OpportunitiesUltrahigh-pressure size-exclusion chromatography (UHPSEC) can potentially offer a new direction and overcome some of the disadvantages (for example, limited resolution and long analysis time) associated with conventional SEC analysis. UHPSEC is based on using sub-3-µm silica-organic hybrid particles under elevated pressures (often above 400 bar) to improve the separation efficiency and increase analysis speed. In spite of the benefits promised by the chromatographic theory, there are some uncertainties that may limit the proliferation of UHPSEC in polymer analysis. As a result of possible issues associated with the use of a different stationary phase - including secondary interactions and polymer degradation - it is unclear whether UHPSEC will provide results comparable to those of traditional SEC methods. In this article, the advantages and challenges of UHPSEC for the analysis of different engineering thermoplastics are discussed, as well as a comparison of results obtained with UHPSEC and conventional SEC.
Latest:
Aggregated Singletons for Automated Purification WorkflowAggregated singletons for automated purification workflow delivers 30 mM DMS solutions for biological screening.
Latest:
Practical Considerations of Capillary Electrophoresis–Mass Spectrometry for Analysis of BiotherapeuticsIn this article, we discuss the use of CE-MS (sheath flow interface) for analysis of intact proteins as well as of protein digests. We discuss the unique aspects that the user needs to be aware of while testing biotherapeutics versus small molecule drugs. We also highlight that the optimization of CE and MS parameters together result in the creation of a more robust and reproducible protein analysis approach. Finally, we list some of the most common errors that are likely to occur during CE-MS analysis and suggest ways to overcome them.
Latest:
Practical Considerations of Capillary Electrophoresis–Mass Spectrometry for Analysis of BiotherapeuticsIn this article, we discuss the use of CE-MS (sheath flow interface) for analysis of intact proteins as well as of protein digests. We discuss the unique aspects that the user needs to be aware of while testing biotherapeutics versus small molecule drugs. We also highlight that the optimization of CE and MS parameters together result in the creation of a more robust and reproducible protein analysis approach. Finally, we list some of the most common errors that are likely to occur during CE-MS analysis and suggest ways to overcome them.
Latest:
Mitigating the Effect of Surfactants in Sample Preparation of a Phospholipid Formulation for Impurities Analysis by Reversed-Phase Liquid ChromatographyA surfactant based diluent was used in sample preparation for reversed phase HPLC analysis of a drug product and its impurities in a phospholipid formulation. The use of the didodecyl trimethylammonium bromide (DDAB) enabled a consistent, quantitative extraction of the analytes of interest from the lipid matrix in a much more aqueous, weak solvent. Water was added as an anti-solvent to precipitate out the surfactant from the system to eliminate HPLC injection pressure spikes, enabling large volume injections and achieving a consistent, robust method for long term use. Method development and validation steps are described.
Latest:
Mitigating the Effect of Surfactants in Sample Preparation of a Phospholipid Formulation for Impurities Analysis by Reversed-Phase Liquid ChromatographyA surfactant based diluent was used in sample preparation for reversed phase HPLC analysis of a drug product and its impurities in a phospholipid formulation. The use of the didodecyl trimethylammonium bromide (DDAB) enabled a consistent, quantitative extraction of the analytes of interest from the lipid matrix in a much more aqueous, weak solvent. Water was added as an anti-solvent to precipitate out the surfactant from the system to eliminate HPLC injection pressure spikes, enabling large volume injections and achieving a consistent, robust method for long term use. Method development and validation steps are described.
Latest:
Food Metabolomics: Fact or Fiction?The different aspects of food metabolomics are described using tomato taste as an example.
Latest:
Phenolic Compounds in Barrel-Aged Alcoholic BeveragesThis Application Note describes UHPLC methods to simultaneously separate and identify seven tannin compounds as aging markers in barrel-aged alcoholic beverages. The proposed methodology was applied to four different matrixes: whisky, brandy, rum, and tequila, to demonstrate a correlation between aging time and total tannin concentration level.
Latest:
Ultrafast Analysis of Food PreservativesThis Application Note demonstrate ultrafast gradients with an over 60 % reduction of analysis time using the Agilent 1290 Infinity II Multisampler with dual-needle function and alternating column regeneration.
Latest:
Separation of Amino Acid Enantiomers Using Capillary Electrophoresis with a New Chiral LigandA chiral ionic liquid, namely 1-ethyl-3-methyl imidazole L-tartrate ([EMIM][L-Tar]), was applied as a new chiral ligand for the separation of tryptophan, tyrosine, and phenylalanine enantiomers by chiral ligand exchange capillary electrophoresis (CE). To validate the unique behaviour of [EMIM][L-Tar], the performance of L-tartaric acid and 1-ethyl-3-methyl imidazole L-proline as chiral ligands was investigated to make a comparison with [EMIM][L-Tar]. Then the separation mechanism was further discussed. It was proven that [EMIM][L-Tar] was a good chiral ligand and would have good application prospects in separation science.
Latest:
Separation of Amino Acid Enantiomers Using Capillary Electrophoresis with a New Chiral LigandA chiral ionic liquid, namely 1-ethyl-3-methyl imidazole L-tartrate ([EMIM][L-Tar]), was applied as a new chiral ligand for the separation of tryptophan, tyrosine, and phenylalanine enantiomers by chiral ligand exchange capillary electrophoresis (CE). To validate the unique behaviour of [EMIM][L-Tar], the performance of L-tartaric acid and 1-ethyl-3-methyl imidazole L-proline as chiral ligands was investigated to make a comparison with [EMIM][L-Tar]. Then the separation mechanism was further discussed. It was proven that [EMIM][L-Tar] was a good chiral ligand and would have good application prospects in separation science.
Latest:
Separation of Amino Acid Enantiomers Using Capillary Electrophoresis with a New Chiral LigandA chiral ionic liquid, namely 1-ethyl-3-methyl imidazole L-tartrate ([EMIM][L-Tar]), was applied as a new chiral ligand for the separation of tryptophan, tyrosine, and phenylalanine enantiomers by chiral ligand exchange capillary electrophoresis (CE). To validate the unique behaviour of [EMIM][L-Tar], the performance of L-tartaric acid and 1-ethyl-3-methyl imidazole L-proline as chiral ligands was investigated to make a comparison with [EMIM][L-Tar]. Then the separation mechanism was further discussed. It was proven that [EMIM][L-Tar] was a good chiral ligand and would have good application prospects in separation science.
