Authors
Latest:
Spectroscopy Is Applied Quantum Mechanics, Part IV: Ideal SystemsIn Parts I-III of this series, columnist David W. Ball recounted the failings of classical mechanics, the quantum hypothesis, and the rise of a new theory called quantum mechanics. In this installment, he discusses the ideal systems whose wavefunctions can be determined exactly from the Schr?dinger equation.
Latest:
Targeted Quantitative Protein Analysis in Human Serum Using High-Resolution Multiple Selected Reaction Monitoring AssaysA common endpoint for a biomarker discovery experiment is a list of putative marker proteins. The next step is then to perform targeted quantitative measurements of these proteins in an expanded patient population to assess their validity as markers. Analytical accuracy and precision are required for unambiguous quantitative analysis of targeted proteins from very complex mixtures. Wide dynamic range and high sensitivity are critical for detecting low-abundance proteins. Such an assay also is appropriate for "targeted discovery" experiments, where the goal is to quantitate a large number (up to hundreds) of known proteins in a complex sample.
Latest:
Rapid Micro-Sampling by ATR/FT-IRIn ATR/FT-IR, magnified visual monitoring of a sample benefits many applications. For micro-sampling and defect analysis, viewing capabilities decrease overall measurement time by allowing the user to locate the desired sampling area quickly and enhance confidence in the collected data by assuring the sampling point. Visual changes in the sample also may be easily monitored during testing. As an example application, the ease of micro-sampling is shown through fiber analysis and the results are discussed.
Latest:
Electron-Capture Dissociation in a Radio-Frequency Linear Ion TrapHere we describe a new compact device for electron-capture dissociation (ECD) analysis of large peptides and posttranslational modifications of proteins, which can be difficult to analyze via conventional dissociation techniques such as collision-induced dissociation (CID). The new compact device realizes ECD in a radio frequency (RF) linear ion trap equipped with a small permanent magnet, which is significantly different than the large and maintenance-intensive superconducting magnet required for conventional ECD in Fourier-transform ion cyclotron resonance mass spectrometers. In addition to its compactness and ease of operation, an additional merit of an RF linear ion trap ECD is that its reaction speed is fast, comparable to CID, enabling data acquisition on the liquid-chromatography (LC) time scale. We interfaced the linear-trap ECD device to a time-of-flight mass spectrometer to obtain ECD spectra of phosphorylated peptides injected into a liquid chromatograph, infused glycopeptides, and intact small..
Latest:
High-Resolution Ultrasonic Spectroscopy: Analysis of Microemulsions (PDF)This article introduces the application of high-resolution ultrasonic spectroscopy for the analysis of emulsions and suspensions.
Latest:
Finding Education, Mentorship, and Success in Your Spectroscopy CareerSeeking opportunities for career growth is important for early-career scientists to explore new skills, connect with mentors, and gain insights into the field. Professional societies and educational programs can be invaluable resources, providing mentorship, training, and networking opportunities that can accelerate career success in spectroscopy.
Latest:
Raman Microscopy in Art and Archeology: Illumination of Historical Mysteries in Rock Art and Frescoes (PDF)This article describes the use of Raman microscopy to investigate historical mysteries in rock art and frescoes.
Latest:
High Resolution 1H NMR Spectroscopy of Metabolically Active Microorganisms Using Non-Destructive Magic Angle Spinning (PDF)The authors show that high resolution 1H nuclear magnetic resonance (NMR) spectroscopy can be used to study biofilm metabolism under environmentally relevant conditions in a minimally invasive way.
Latest:
Peptide Mapping of Monoclonal Antibodies and Antibody–Drug Conjugates Using Micro-Pillar Array Columns Combined with Mass SpectrometryThe structural complexity of monoclonal antibodies (mAbs) challenges the capabilities of even the most advanced chromatography and mass spectrometry techniques. This study examines the use of micro-pillar array columns in combination with mass spectrometry for peptide mapping of both mAbs and antibody–drug conjugates (ADCs).
Latest:
From the Editor – Hot Topics in Spectroscopy: The SciX 2021 Preview and Companion GuideThis issue contains interviews that provide an excellent sampling of the fascinating science that will be presented at this year’s SciX conference.
Latest:
Resonance Light Scattering Spectrum of the Alizarin Green-CTMAB-Nucleic Acids System and Determination of Nucleic Acids at Nanogram LevelsThe study of the interaction mechanism of nucleic acids-CTMAB with AG showed that the enhanced RLS comes from the aggregation of AG on nucleic acids through the bridged and synergistic effect of CTMAB.
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. The authors adopted a nano liquid chromatography (nLC)–linear ion trap time-of-flight (LIT-TOF) MS system and newly developed software known as information-based acquisition (IBA) to identify biomarkers in human serum. IBA is a data processing protocol for repetitive MS analyses. Peptides selected for the first-pass MS-MS analysis are automatically excluded from the MS spectrum such that subsequent MS-MS analyses are performed on different peptides to minimize overlapping analyses, resulting in the identification of relatively low-abundant peptides.
Latest:
Electron-Capture Dissociation in a Radio-Frequency Linear Ion TrapHere we describe a new compact device for electron-capture dissociation (ECD) analysis of large peptides and posttranslational modifications of proteins, which can be difficult to analyze via conventional dissociation techniques such as collision-induced dissociation (CID). The new compact device realizes ECD in a radio frequency (RF) linear ion trap equipped with a small permanent magnet, which is significantly different than the large and maintenance-intensive superconducting magnet required for conventional ECD in Fourier-transform ion cyclotron resonance mass spectrometers. In addition to its compactness and ease of operation, an additional merit of an RF linear ion trap ECD is that its reaction speed is fast, comparable to CID, enabling data acquisition on the liquid-chromatography (LC) time scale. We interfaced the linear-trap ECD device to a time-of-flight mass spectrometer to obtain ECD spectra of phosphorylated peptides injected into a liquid chromatograph, infused glycopeptides, and intact small..
Latest:
ICP-MS: When Sensitivity Does MatterIt makes intuitive sense - the higher the sensitivity of an inductively coupled plasma–mass spectrometry (ICP-MS) system, the lower the detection limit. But there are many factors that affect the detection limit for a given isotope in a given sample. These factors include sensitivity, background noise, and interferences.
Latest:
High Resolution 1H NMR Spectroscopy of Metabolically Active Microorganisms Using Non-Destructive Magic Angle Spinning (PDF)The authors show that high resolution 1H nuclear magnetic resonance (NMR) spectroscopy can be used to study biofilm metabolism under environmentally relevant conditions in a minimally invasive way.
Latest:
ICP-MS: When Sensitivity Does MatterIt makes intuitive sense - the higher the sensitivity of an inductively coupled plasma–mass spectrometry (ICP-MS) system, the lower the detection limit. But there are many factors that affect the detection limit for a given isotope in a given sample. These factors include sensitivity, background noise, and interferences.
Latest:
Advances in TOF-MS-Based Screening for Food Safety Residue Analysis with a Positive ApproachMass spectrometry plays an increasingly significant role in the analysis of residues and contaminants in food. Here we will illustrate how the combination of ultrahigh-pressure liquid chromatography (UHPLC) and high-resolution time-of-flight-mass spectrometry (TOF-MS) is used to generate a screen of veterinary drug residues in products of animal origin. The use of UHPLC–TOF-MS and dedicated, workflow directed software allows rapid screening for large numbers of residues and automated quantification of positive samples. In addition, we illustrate how the data generated using MSE acquisition mode enable critical structural information to be collected, which offers additional selectivity and confirmatory data for compound identification and facilitates elucidation of the structure of newly discovered compounds.
Latest:
Analysis of Mycotoxins in Various Cattle Forages and Food Matrices with the TSQ Quantum Discovery MAXThermo Fisher Scientific
Latest:
Molecular Spectroscopy Workbench: Thin-Film Filters for Raman Spectroscopy (PDF)Recent advances in thin-film filter technology have enabled dramatic improvements in the performance of filters for laser-based analytical instrumentation.
Latest:
Analysis of a Bispecific Antibody Using SEC–MSThis article describes a workflow using nontargeted liquid chromatography–tandem mass spectrometry (LC–MS/MS) for reliable compound identification.
Latest:
Atomic Spectroscopy in Practice: A Joint Virtual Conference Presented by Spectroscopy Magazine and The Society for Applied Spectroscopy***Live: Tuesday February 23, 2021 & Wednesday February 24, 2021*** Spectroscopy magazine and the Society for Applied Spectroscopy (SAS) are pleased to present a joint virtual conference on February 23 and 24, 2021, called “Atomic Spectroscopy in Practice.” This two-day event will provide highly practical information for atomic spectroscopists and analytical laboratory staff working with molecular atomic techniques. *** On demand available after final airing until Feb. 24, 2022***
Latest:
How to Design a Miniature Raman SpectrometerIn this article, we describe the key factors that influence the overall size of a spectrometer, such as the diffraction grating groove density and detector size. Furthermore, we demonstrate compact Raman spectrometer designs as small as 30 mm × 30 mm in footprint by using highly dispersive gratings and uncooled detectors.
