Analytical Instrument Documents

Matrix-Assisted Laser Desorption Ionization (MALDI) has been applied to a wide range of analyses and is particularly suitable for the qualitative analysis of high molecular weight samples. On the other hand, MALDI is generally considered unsuitable for low molecular weight compounds because the matrix ions interfere with sample ion detection in the low mass region. However, if these low m/z ions can be separated from each other and distinguished with sufficiently high mass resolving power, then MALDI can be expanded to the analysis of low-molecular-weight compounds. We have demonstrated this by using the JEOL MALDI SpiralTOF mass spectrometer The innovative Spiral orbital technology consisting of 4 sets of toroidal electrical sector and Matsuda plates provides ultra-high mass resolving power combined with high ion transmission. Here we report the use of Spiral technology to collect high mass-resolving power and high mass-accuracy data for eight triazine compounds. Additionally, we report TOF-TOF data obtained with monoisotopic precursor ion selection to provide clear product-ion mass spectra for each compound.

A high-resolution MALDI/TOF-TOF system with unique ion optics is applied to the identification of polymers and polymer additives. Exact mass measurements and isotopic abundances were used to identify elemental compositions. High-energy collision-induced dissociation with monoisotopic precursor selection provided structural information for additives and polymers. The mass accuracy for the sodiated molecule of Irganox 1010 in polymethyl methacrylate (PMMA) was within 1ppm of the calculated m/z (m/z 1199.7733, C73H108O12Na+). The high-energy CID product-ion mass spectrum for sodiated Irganox 1010 shows bond cleavage with little or no rearrangement. Four types of product ions are identified for the high-energy CID product-ion mass spectra of sodiated PMMA ions.

The JMS-S3000 SpiralTOF™ is a MALDI-TOF MS that uses an innovative spiral ion optics system to achieve the highest resolution currently available for a MALDI instrument. As a result, small organic molecules can be analyzed on this system with minimal interferences from the matrix peaks. Additionally, the JMS-S3000 is available with a TOF-TOF option that can acquire highenergy collision-induced dissociation (CID) product ion spectra for monoisotopically selected precursor ions. In this work, we analyzed several small organic molecules by using the JMS-S3000 with the TOF-TOF option.

Matrix assisted laser desorption ionization (MALDI) is a powerful and useful ionization technique that is commonly used for the analysis of biomolecules such as oligosaccharides. There are many applications of oligosaccharides in which various ionization techniques and mass spectrometers were used for their analysis [1]. In particular, tandem mass spectrometry techniques are often used to sequence these molecules. Recently, JEOL developed a new tandem TOF-TOF instrument coupled with MALDI that is called the Spiral- TOF. The 1st TOF consists of 4 toroidal electric sectors that fold a 17 meter flight path into a one meter box. This design provides several unique advantages for TOF-TOF analysis. The 2nd TOF has (a) 20 kV high-energy CID, (b) monoisotopic precursor ion selection, and (c) no PSD ions in the product ion mass spectrum. In this study, we analyzed several oligosaccharides by using the JMS-S3000 SpiralTOF-TOF tandem mass spectrometer system.

Lysine and glutamine are not easily distinguished by the most common approaches to peptide sequencing which involve mass spectrometers with low to moderate resolving power and low-energy collision-induced dissociation (CID). Lysine (C6H14N2O2 with a mass of 146.1055 u) and glutamine (C5H10N2O3 with a mass of 146.0691) differ by only 0.036 u. In this study, we demonstrate the measurement of a mixture of Substance P and a synthesized peptide (3-Gln ) with glutamine substituted for lysine in the Susbstance P sequence. Because the mass difference between Substance P and 3-Gln is 0.036 u, a resolving power of greater than 37,000 is required to separate each peptide. Additionally, we show that the TOF-TOF mode can be used to distinguish lysine and glutamine in these peptides by comparing the peak area ratio between a ions and d ions in the high-energy CID mass spectra.

The JMS-3000 SpiralTOF™ has an optional TOF-TOF mode that features monoisotopic precursor ion selectivity, elimination of post source decay (PSD) ions, and high energy collision induced dissociation (CID). The JMS-700T MStation four-sector tandem double focusing mass spectrometer, although featuring a different analyzer and ionization techniques, has similar capabilities that have been previously used for a wide variety of applications including the structural analysis of complex biological molecules. In this work, we compare the SpiralTOF-TOF with the MStation four sector tandem double focusing mass spectrometer using the same sample for MS/MS analysis.

Yessotoxin (YTX) is one of the substances that cause food poisoning when humans consume toxic shellfish. The structure of this compound has been previously analyzed by high-energy collision induced dissociation (CID) using a traditional four sector tandem double focusing mass spectrometer. In this work, we analyzed YTX by using a JMS-S3000 SpiralTOF™ equipped with the optional TOF-TOF analyzer to generate a high energy CID product ion spectrum.

Sperm activating and attracting factor (SAAF) is a naturally occurring substance produced by ascidians (sea squirts) to promote the fertilization process. Previously, the structure of this compound was characterized by high-energy collision induced dissociation (CID) using a traditional four sector tandem double focusing mass spectrometer. In this work, we analyzed the SAAF from a ciona intestinalis by using a JMS-S3000 SpiralTOF™ equipped with the optional TOF-TOF analyzer to generate a high energy CID product ion spectrum for this compound.

Phosphorylation is a type of post-translational modification of proteins that is used for the intracellular signal transduction in a wide range of living species. For this reason, it is very important to determine where the protein (amino acid) is phosphorylated. In this work, we measure a monophosphopeptide (FQ pS EEQQQTEDELQDK) that was obtained from the tryptic digestion of β-casein (Bovine) using the TOF-TOF option that is available for the JEOL Spiral- TOF™ system.

Industrial materials are often evaluated by surface analysis instruments that provide information on surface elements, bonding states, and functional groups. However, there are limited options for surface analysis techniques that provide molecular weight and molecular structure information for organic compounds present on surfaces. Matrix Assisted Laser Desorption Ionization - Time of Flight Mass Spectrometry (MALDI-TOFMS) is a soft ionization technique that can be used to analyze surfaces in order to estimate elemental compositions with accurate mass measurements, obtain structural information by using MS/MS, and map surface compounds by using MS imaging. MALDI-TOFMS uses a high voltage on the target plate to accelerate the ions into the TOFMS analyzer. Therefore, the target plates are conductive and are typically made of stainless steel. MALDI imaging mass spectrometry is widely used for analyzing organic substances on frozen tissue sections. In this case, a frozen tissue section with a thickness of about 10 μm is placed on a conductive glass slide coated with an indium tin oxide (ITO) film. However, for the analysis of industrial products, the target organic compounds are on nonconductive substrates such as resins with millimeter thicknesses. MALDI-TOFMS surface measurements using nonconductive substrates lead to a reduction in mass resolution and a significant decrease in ion intensity due to surface charging. This problem can be solved by pretreating the surface with gold vapor deposition in order to change it from nonconductive to conductive. This method was previously shown to work well in MSTips No. 204 in which the gold vapor deposition method was applied to the MALDI-MS imaging analysis of inks on paper. In this report, we used gold vapor deposition to look at samples on the surface of a 1 mm thick acrylic plate.

rss

Other Resources

Image Gallery
  • View a selection of NMR and MS spectra
  • 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
  • Media

    Corona - Glow Discharge (DART Ion Source)

    January 28, 2022
    2713
    JEOL Ltd. global website
      JEOL USA, Inc.
      11 Dearborn Road
      Peabody, MA 01960
      © Copyright 2023 by JEOL USA, Inc.
      Terms of Use
      |
      Privacy Policy
      |
      Cookie Preferences