Analytical Instrument Documents

Average molecular weight is an important reference for evaluating samples with molecular weight distributions, such as crude oils, which are complex mixtures, or synthetic polymers. Almost all of the ions observed in field desorption (FD) and field ionization (FI) mass spectra are molecular ions because they are both soft ionization methods. As a result, the average molecular weight of a sample can be calculated directly from the masses (or “m/z”) and intensities for all of the ions observed in the FD or FI mass spectra. By applying group-type analysis, the components can be classified into types based on their functional groups and/or unsaturations. Average molecular weight, polydispersity index, or relative abundance of each type can be obtained.

The FastGC method is a very useful technique for doing rapid GC analyses that result in extremely narrow chromatographic peaks over a shorter time period than traditional GC analyses. Additionally, time-of-flight mass spectrometers (TOFMS) are capable of very fast data acquisition in comparison with other types of mass spectrometers so they are well suited as the detector for the FastGC technique. Furthermore, when the TOFMS is capable of high resolution measurements, the resulting mass spectra contain accurate mass information that can be used to calculate the elemental compositions for each observed m/z. In this application note, we describe the quanitative analysis of pyrazole pesticides (Fipronil, Ethiprole, Pyraflufen ethyl and Tebfenpyrad) on tea leaves by FastGC/HRTOFMS. Additionally, we confirm that a rapid analysis with high sensitivity is easy to perform and very useful for fast screening.

The FastGC method is a very useful technique for doing rapid GC analyses that result in extremely narrow chromatographic peaks over a shorter time period than traditional GC analyses. Additionally, time-of-flight mass spectrometers (TOFMS) are capable of very fast data acquisition in comparison with other types of mass spectrometers so they are well suited as the detector for the FastGC technique. Furthermore, when the TOFMS is capable of high resolution measurements, the resulting mass spectra contain accurate mass information that can be used to calculate the elemental compositions for each observed m/z. In this application note, we describe the qualitative analysis of pyrazole pesticides (Fipronil, Ethiprole, Pyraflufen ethyl and Tebfenpyrad) on tea leaves by FastGC/HRTOFMS. Additionally, we confirm that a rapid analysis with high sensitivity is easy to perform and very useful for fast screening.

Comprehensive two-dimensional gas chromatography (GC×GC) is a kind of continuous heart-cut GC system. Two different types of columns are connected via a modulator in the same GC oven. By using the two columns together, this technique provides very high separation capabilities when compared to one- dimensional GC analysis. However, GC×GC systems require a fast data acquisition detection system in order to record the very narrow time width peaks observed in the GC chromatograms. The JEOL AccuTOF-GC is a time-of-flight mass spectrometer (TOFMS) that fully meets this high speed data acquisition requirement at 25Hz (0.04sec) so it can be successfully used as the detection system in combination with GC×GC. In this work, the AccuTOF-GC was used for the qualitative analysis of polycyclic aromatic hydrocarbons in kerosene by GC×GC -TOFMS.

Comprehensive two-dimensional gas chromatography (GC×GC) is a kind of continuous heart-cut GC system. Two different types of columns are connected via a modulator in the same GC oven. By using the two columns together, this technique provides very high separation capabilities when compared to one-dimensional GC analysis. However, GC×GC systems require a fast data acquisition detection system in order to record the very narrow time width peaks observed in the GC chromatograms. The JEOL AccuTOF-GC is a time-of-flight mass spectrometer (TOFMS) that fully meets this high speed data acquisition requirement at 25Hz (0.04sec) so it can be successfully used as the detection system in combination with GC×GC. In this work, the AccuTOF-GC was used to analyze kerosene and diesel oil samples by GC×GC -TOFMS.

JEOL has recently announced a 4th generation GC/HR-TOFMS system, the JMS-T200GC AccuTOF-GCx, in 2015. The AccuTOF-GCx offers high sensitivity, high mass resolving power, high mass accuracy, and a wide dynamic range in combination with high-speed data acquisition. In this application note, we show the high sensitivity measurement capability using this latest GC/HR-TOFMS system.

JEOL has recently announced a 4th generation GC/HR-TOFMS system, the JMS-T200GC AccuTOF GCx, in 2015. The AccuTOF-GCx offers high sensitivity, high mass resolving power, high mass accuracy, and a wide dynamic range in combination with high-speed data acquisition. In this application note, we show the high mass resolution that can be obtained with this latest GC/HR-TOFMS system.

JEOL has recently announced a 4th generation GC/HR-TOFMS system, the JMS-T200GC AccuTOF-GCx, in 2015. The AccuTOF-GCx offers high sensitivity, high mass resolving power, high mass accuracy, and a wide dynamic range in combination with high-speed data acquisition. In this application note, we show we show high mass accuracy and m/z stability using this latest GC/HR-TOFMS system.

The characteristics of polymeric materials vary depending on the additives. Consequently, a variety of additives can be added into the raw polymer resin in order to achieve the required characteristics for the product. PY/GC/MS is often used as an analytical method for the analysis of polymeric materials. However, PY/GC/MS is often insufficient for the chromatographic separation of additives and thermal decomposition products from the polymer. As a result, it is often difficult to assign compound identities. On the other hand, comprehensive two-dimensional gas chromatography/high resolution time-of-flight mass spectrometry (GCxGC/HRTOFMS) is a well-known technique that provides high chromatographic separation by using two different polarity GC columns. Additionally, when this technique is used with high resolution mass measurements, it can be a powerful tool for estimating elemental compositions of analytes found within a complex mixture. In this application note, the additives were identified within a commercially available molded polymer by using pyrolysis (PY)/GCxGC/HRTOFMS.

The comprehensive 2-dimensional GC (GC x GC) technique provides higher-separation capabilities for complex mixtures than the typical 1-dimensional GC measurements. However, the GC x GC technique requires high speed data acquisition, e. g. > 20 Hz, for the GC detectors due to the shorter 2nd GC column which elutes samples within just a few seconds (comparable to those used for the ultra-fast GC measurements). 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. In fact, this instrument can measure data using up to a 50 Hz data acquisition speed which is more than sufficient to do not only fast GC measurements but also GC x GC measurements.