Analytical Instrument Documents

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.

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.

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.

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.

Download all eight Delta QuickTime movie tutorials.

How to acquire and process proton spectra: process lists in 1D Processor, using the Pointer Tools to interact with data, peak picking, J-coupling tool, integration, plotting.

How to acquire and process 1D, 2D, nOe spectra: comparing multiple data sets in Data Slate, loading high-resolution projections, Level Tool, plotting, understanding through-bond correlations, common nOe experiments, data interpretation.

A comprehensive description and demonstration of contouring data with Level Tool.

How to acquire and process HMBC spectra: loading high-resolution projections, Level Tool, plotting, understanding HMBC, data interpretation.

How to acquire and process multiplicity-edited HSQC spectra: phasing 2D data, loading high-resolution projections, setting contrast colors in Level Tool, plotting, HMQC versus HSQC, data interpretation.

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Other Resources

Walkup NMR
  • See how the Delta NMR software allows users to just "walk up" and start NMR experiments
  • Mass Spec Reference Data
  • View our page of useful molecular references for Mass Spec
  • Tutorials (Mass Spec)
  • Documents on the basics of mass spectrometry
  • Delta NMR software Tutorials
  • Videos on how to use the Delta NMR software
  • No-D NMR
  • Description of No-D NMR and how it can be used to eliminate the need for deuterated solvents
  • Non Uniform Sampling (NUS)
  • Description of how NUS is used to greatly reduce the time needed for running NMR experiments
  • NMR Basics
  • Overview of the Basics of NMR Theory
  • NMR Magnet Destruction
  • See our presentation of the slicing open of a JEOL Delta-GSX 270 MHz NMR Magnet
  • NMR Training
    Basic Operations and System Management for JEOL NMR Users
    Mass Spec Training
    Learn more about spectrometer operation and maintenance, data collection and processing, and advanced MS software operation.
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    We publish and send out this NMR newsletter to our customers. They can also be viewed here.
    Mass Media Newsletter
    We publish and send out this Mass Spec newsletter to our customers. They can also be viewed here.
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