MALDI-ISD Measurements Using Both the SpiralTOF Mode and the LinearTOF Mode March 5, 2020 Application Note, Mass Spectrometry (MS), SpiralTOF™ 0 Introduction Matrix assisted laser desorption/ionization (MALDI) combined with in-source decay (ISD) is a useful tool for doing top-down sequencing of intact proteins. In this work, we measured and compared the ISD fragment ions generated for several proteins by using both the high resolution MALDI-Spiral mode and the high sensitivity MALDI-Linear mode available on the JEOL SpiralTOF MALDI-MS system. Experimental Myoglobin and Bovine serum albumin (BSA) protein samples were separately dissolved into 0.1% trifluoroacetic acid aqueous with the concentration fixed at 10 pmol/μL. 1,5-diaminonaphthalene (DAN), which can provide good S/N for ISD fragment ions [1], was used as the MALDI matrix. The DAN matrix was dissolved to 0.1% trifluoroacetic acid aqueous/ 50% acetonitrile with the matrix concentration fixed at 10 mg/mL. Subsequently, the matrix and the sample solutions were mixed 1/1 (v/v), and then 1 μL of each solution was deposited and dried on the MALDI target plate. Afterwards, each sample was analyzed in triplicate on the JEOL JMS-3000 SpiralTOF by using both the SpiralTOF mode and the LinearTOF mode. For full details: Attached files often contain the full content of the item you are viewing. Be sure and view any attachments. MALDI-ISD Measurements Spiral and Linear.pdf 1.27 MB Related Articles GCxGC-EI and GCxGC-FI Measurements Using the EI-FI Combination Ion Source Comprehensive 2-dimensional GC (GC x GC) provides higher-separation capabilities for complex mixtures than the typical 1-dimensional GC measurements. However, this technique requires high speed data acquisition, e. g. > 20 Hz, for the GC detectors due to the shorter 2nd GC column (comparable to those used for the ultra-fast GC measurements) which elutes samples within just a few seconds. Recently, JEOL has developed a new generation GC-HRTOFMS system called the “AccuTOF GCv 4G”. The AccuTOF GCv 4G has high sensitivity, high resolution, high mass accuracy and high speed data acquisition, all simultaneously. Also JEOL has developed a unique EI/FI combination ion source for this system which provides the capabilities of GC/EI and GC/FI measurements without having to break vacuum in order to switch between each ionization mode. Additionally, this combination is particularly powerful in that it provides library searchable fragmentation information by using EI and high mass accuracy molecular ion information by using FI. Comparison of the JMS-S3000 SpiralTOF-TOF and a 4-Sector Tandem Double-Focusing Mass Spectrometer 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. Analysis of organic compounds on an acrylic plate using JMS-S3000 SpiralTOF™ - MSTips - 251 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. Analysis of organic compounds on an acrylic plate using JMS-S3000 "SpiralTOF" 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. Analysis of organic compounds on an acrylic plate using JMS-S3000 "SpiralTOFTM" 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. MALDI-Imaging MS of Lipids on Mouse Brain Tissue Sections Using Negative Ion Mode The main biological functions of lipids include energy storage, signaling, and acting as structural components of cell membranes. Not only their chemical composition and structures but also the distributions in biological body are important for biochemistry. Matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-Imaging MS) is a powerful tool for the biochemical analyses of surfaces. Different lipid types are observed in positive or negative-ion MALDI mass spectra, depending on the presence of polar functional groups. Phosphatidyl cholines and galactosyl ceramides were mainly observed in the MALDI-Imaging MS of positive ion mode using JMS-S3000 SpiralTOF[1]. In this work, we report the use of the SpiralTOF for negative-ion MALDI-Imaging MS of sulfatides. High-resolution, accurate mass data and MS/MS data obtained under high-energy CID conditions provide information about structures, elemental compositions, and localization of many types of sulfatides. Showing 0 Comment Comments are closed.