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Documentation in support of your JEOL product.

Integrated Analysis of Coffee Aroma by using a Headspace GC-HRMS - MSTips 280

Electron ionization (EI) is a hard ionization method that is commonly used with gas chromatography mass spectrometry (GC-MS). The mass spectral fragmentation patterns produced by EI are used for library database searches to identify compounds. Conversely, soft ionization methods like field ionization (FI) tend to produce clear molecular ions with minimal fragmentation. When high-resolution MS is used with these ionization techniques, the accurate masses for the fragment ions produced by EI and the molecular ions produced by soft ionization provide an additional dimension of information for the analytes. Combining the exact mass information with the results of conventional library search can enhance the accuracy of identification compared to the use of library search alone.  In this work, we introduce the msFineAnalysis software and use it to automatically combine data acquired by GC/EI and GC/soft ionization for the qualitative analysis of coffee headspace.

Integrated Analysis of an Acrylic Resin using msFineAnalysis v2 - MSTips 300

In 2018, msFineAnalysis Ver.1 software was released in which data acquired by EI, soft ionization, and accurate mass measurements were automatically integrated to generate a qualitative report for samples measured by these techniques with GC-MS. Recently, msFineAnalysis Ver.2 was introduced as an enhanced version with additional features. In this work, we will describe the changes in Ver.2, which now includes chromatographic deconvolution, and present applications using the new features.

Analyzing a Specific Component using Group Analysis of msFineAnalysis Ver. 2 - MSTips 303

In 2018, we announced the msFineAnalysis software which was designed to automatically integrate two types of data acquired by EI and soft ionization. Recently, we developed msFineAnalysis Version 2, an enhanced version with additional features. msFineAnalysis Version 2 incorporates two new features: Chromatographic Deconvolution and Group Analysis. In this work, we use the group analysis capabilities of the software to evaluate the pyrolysis GC-MS results for a vinyl acetate resin.

Flavones and Flavor Components in Two Basil Leaf Chemotypes

The chemical composition of herbs and spices can vary dramatically between different species and different growing conditions. Herbs grown under different conditions that have different essential oil compositions are referred to as chemotypes. Basil is an herb that has widely varying chemotypes. The difference between basil leaves from two different sources was easily observed by using DART. A leaf from a basil plant purchased at a grocery store was compared with a leaf from a Vietnamese restaurant. A small particle from each leaf was analyzed placed in front of the DART source. Mass spectra were obtained within seconds. Elemental compositions were confirmed by exact masses and accurate isotopic abundance measurements.

Direct Analysis in Real Time (DART®) Mass Spectrometry

Mass Spectrometry (MS) is one of the fastest-growing areas in analytical instrumentation. The use of mass spectrometry in support of synthetic, organic, and pharmaceutical chemistry is well established. Mass spectrometry is also used in materials science, environmental research, and forensic chemistry. It has also evolved into one of the core methods used in biotechnology. However, currently available ion sources place extreme restrictions on the speed and convenience of sample analysis by mass spectrometry. Here we report a method for using mass spectrometry to instantaneously analyze gases, liquids, and solids in open air at ground potential under ambient conditions. Traditional ion sources used in mass spectrometry require the introduction of samples into a high vacuum system.

Cryogenic probes: the development of “UltraCOOL” & “SuperCOOL” probes

In 2013, JEOL RESONANCE launched the cryogenic NMR probe systems,”UltraCOOL” and “SuperCOOL”. Delivering sensitivity far exceeding conventional room temperature probes together with ease of use beyond that previously associated with cooled probes, such as probe change whilst cooled, and variable temperature measurement capability, the products received a lot of positive response. However, many dramatic stories lay behind the birth of these products.

X-ray, Electron and NMR Crystallography to Structural Determination of Small Organic Molecules

Here we present the recent development at RIKEN CLST-JEOL collaboration laboratory to explore the molecular structures of low-molecular weight pharmaceutical compounds in natural abundance (without any isotopic labeling); the recent progress in fast magic angle spinning (MAS) technology in solid-state nuclear magnetic resonance (ssNMR) and in ultra high sensitivity camera in transmission electron microscopy (TEM) paves a new way to answer problems in the pharmaceutical industry and sciences. 1) Crystalline polymorphs and 2) salt/cocrystal are two major concerns in terms of quality control, stability, and intellectual property. To identify the crystalline form, powder X-ray diffraction and 13C cross-polarization MAS ssNMR are widely used methods, however, the former is sometimes not suitable for mixture analysis and latter fails to distinguish crystalline forms with similar molecular conformations. To solve these issues, we use electron diffraction (ED) and 1H fast MAS NMR. The crystalline form can be determined from nano- to micro-meter sized single crystals using ED, since electron interactions are 4 to 5 order stronger than X-ray interactions. 1H NMR also gives suitable information to molecular packing since 1H is located at the surface of the crystals. The salt/cocrystal issue, where hydrogen plays a key role, is a serious problem, since single crystal X-ray diffraction (SCXRD) cannot determine the hydrogen atom position precisely. Here we determine the internuclear distances between 1H and 15N using ssNMR at fast MAS conditions, while the global structure is obtained through SCXRD, answering the salt/cocrystal questions.

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Corona - Glow Discharge (DART Ion Source)

February 22, 2020
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