Related Articles

• GC-TOFMS Application: Natural Polymer Analysis by using Pyrolysis-GCxGC-MS - "Urushi" analysis with GCxGC/EI and GCxGC/PI

  A Japanese lacquer film called "Urushi" is a natural polymer that has been used as a paint and adhesive for living-wares and craft-wares for approximately 8,000 years. "Urushi" has a complex structure that researchers are trying to understand using pyrolysis-gas chromatograph/mass spectrometer (Py/GC/MS) system. Recently, we developed a new gas chromatograph/high resolution time-of-flight mass spectrometer (GC/HR-TOFMS) system that can be used for comprehensive two-dimensional GC (GCxGC) measurements. Additionally, we have developed a unique combination electron ionization/photoionization (EI/PI) ion source that can be used with this GC/HR-TOFMS system. In this work, we measured "Urushi" samples using this unique Py/GCxGC/HR-TOFMS system in combination with our new combination EI/PI ion source.
• Analysis of Electronics Waste by GCxGC Combined with High-resolution Mass Spectrometry: Using Accurate Mass Information and Mass Defect Analysis to Explore the Data

  Comprehensive two-dimensional gas chromatography (GCxGC) in combination with high-resolution mass spectrometry (HRMS) is a powerful tool for the analysis of complex mixtures. However, new software tools are required to facilitate the interpretation of the rich information content in GCxGC/HRMS data sets. In this work, we analyzed a dust sample collected from an electronics recycling facility by using GCxGC in combination with a new high-resolution time-of-flight (TOF) mass spectrometer. Nontraditional Kendrick Mass Defect (KMD) plots were used to identify halogenated contaminants in an electronics waste sample. Database search results combined with elemental composition determinations from exact-mass data were used to identify (potential) persistent organic pollutants (POPs).
• Component Identification of Mineral Oil Hydrocarbons and Additives in Cardboard Packaging using GCxGC–HRTOF–MS with EI and PI

  Migration of mineral oil from packaging into food has become a health concern, especially since mineral oil affects the liver and lymph nodes. There are two types of mineral oil: mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH). Both types are generally measured using online coupled liquid chromatography–gas chromatography–flame ionization detection 2only to separate and detect target fractions, and it may miss other important, unexpected compounds. By contrast, two-dimensional gas chromatography–high-resolution time-of-flight mass spectrometry (GCxGC–HRTOF–MS) is a comprehensive technique for analyzing complex samples. Using EI with this method allows for NIST database searches. Moreover, using a combination of high-resolution molecular-ion information generated via soft-ionization techniques with an EI NIST database search can result in more-reliable assignments. In this study, we used GCxGC–HRTOFMS with EI and photoionization (PI) soft-ionization techniques to identify compounds in cardboard.
• GCxGC TOFMS Analysis of Base Oils with CI, PI, FI

  Structural elucidation of hydrocarbon classes in petroleum products are always in high demand. Comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GCxGC-TOFMS) with electron ionization (EI) is a powerful method for characterizing complex mixtures such as base oils. However, EI data can often lack a strong molecular ion signal. Therefore, it is necessary to measure samples with soft-ionization methods such as positive chemical ionization (PCI), field ionization (FI), or photo-ionization (PI) for the detection of molecular ions. Each technique is a little different so it is important to understand the characteristics of each soft ionization method. In this application note, we compare the mass spectra of a base oil analyzed by GCxGC-TOFMS with EI, PCI, FI, and PI.
• Using GCxGC/HRTOFMS with EI/FI/PI for component identification and time variation analysis of perfume

  Perfumes are known to be complex mixtures that typically contain a variety of compounds. Their scents are strongly affected by these compounds and their quantity ratios. Additionally, these ratios can change over time, thus changing the perfume’s scent. Two-dimensional gas chromatography/time-of-flight mass spectrometry (GCxGC-TOFMS) is an effective technique for measuring complex samples like perfumes. Using electron ionization (EI) allows for database searches. However, these searches may result in mis-assignments without the additional high-resolution molecular ion information that can be generated through soft ionization techniques. In this study, we used GCxGC-HRTOFMS with EI and the soft ionization techniques of FI (Field Ionization) and PI (Photoionization). Additionally, we measured the changes in intensity over time for the top note/middle note/base note compounds.
• 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.