Analytical Instrument Documents

Automatic structure analysis software for data acquired by electron ionization and soft ionization Designed specifically for GC-HRTOFMS: AccuTOF™ GC-Alpha

DART mass spectrometry commonly uses helium as the DART gas. With the looming helium shortage, other gases are being evaluated for DART.

In this work we used msFineAnalysis to compare Vinyl Acetate Resins that were measured by using Pyrolysis (Py)-GC-MS.

In this work, we compare sensitivity levels when using the combination EI/FI and EI/PI ion sources when He and N2 are used as the GC carrier gas.

The JMS-S3000 SpiralTOF™-plus Ultra-High Mass Resolution MALDI-TOFMS System time-of-flight optics design utilizes a figure-eight ion trajectory to allow a 17m flight path to fit in an extremely small console.

Polymers can be degraded by the effects of light, oxygen, heat, etc. so it is important to understand how the polymer structures change during degradation. Pyrolysis gas chromatograph quadrupole mass spectrometer (Py-GC-QMS) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI-TOFMS) are powerful tools for analyzing polymeric materials. Py-GC-QMS is a method that instantaneously heats a sample with a pyrolyzer and then analyzes the pyrolysis products by GC-MS. Since most of the pyrolysis products are related to monomers and dimers, this technique allows for easy identification of the polymer substructures which is useful for identifying changes to the polymer when degradation occurs. MALDI-TOFMS involves a soft ionization technique that can directly ionize and analyze the intact polymer molecules and often produces singly-charged ions even for high molecular weight compounds. As a result, the m/z axis of the mass spectrum is equal to the mass of the ions, thus making it easy to interpret polymer distributions. Additionally, when MALDI is used with a high-resolution TOFMS, the accurate mass of each ion in the polymer series can be used to calculate their elemental compositions. Moreover, the molecular weight distribution of polymers can be calculated from the ion intensity distribution. In this work, we used Py-GC-QMS and high-resolution MALDI-TOFMS to evaluate the effects of UV irradiation on polymethyl methacrylate (PMMA).

Catalyzed light olefin oligomerization is widely used in petrochemical industries to produce fuels and chemicals. Light olefins such as propene and butenes are commonly selected as feedstocks. Solid phosphoric acid (SPA) and zeolite are representative acidic catalysts. Both the feedstocks and catalysts have an impact on the product composition. In this study, state-of-the-art instrumentation two-dimensional gas chromatography (GC × GC) coupled photoionization─time of flight mass spectrometry was employed to investigate the composition of dodecene products produced from olefin oligomerization. Information such as the olefin congener distribution, dodecene structural subgroup distribution, and individual dodecene isomers was obtained and utilized in the statistical analyses. By using specific data sets of the product composition, the distinguishment between SPA and zeolite catalysts as well as among the feedstocks was achieved by applying the unsupervised screening approaches (principal component analysis and hierarchical clustering analysis). The potential indicators of catalysts and feedstocks were selected by the feature selection methods (univariate analysis: analysis of variance and multivariate analysis: partial least squares-discriminant analysis).

As polymer materials have become more complex and diverse, the details of their chemical composition have become more critical for the end users. This knowledge allows manufacturers and users to understand the effects of incorporating these polymer materials into their products. Additionally, it is critical to also have tools that can quickly compare two-samples to each other like conventional materials versus alternative materials, new products versus old products, and good products versus defective products.

Dioxins are a general term for polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). Their structures consist of two chlorinated rings. Many congeners differ in terms of number of chlorine atoms and binding sites (Fig. 1). These substances are considered as persistent organic pollutants (POPS) due to their presence in the environment and the health risks associated. A World Health Organization (WHO) study has demonstrated the health risks (carcinogenic and immunotoxic) when population are exposed to them. In addition, dioxins have been regulated by the Stockholm convention on POPs in May 2001. In particular, 17 substances have to be monitored because they are regulated (7 PCDDs and 10 PCDFs). The highest toxic compound is the 2378-TeCDD. Currently, dioxins analysis can be done not only using GC-HRMS but also with GC-MS/MS according to European commission regulation (EU644/2017). Especially, GC-triple quadrupole MS is interesting in terms of handling, instrument size and operating costs. Recently, JEOL has developed a new GC-triple quadrupole MS (JMS-TQ4000GC) and a new dedicated dioxins analysis software called TQ-DioK. In this study, we evaluated JMS-TQ4000GC with TQ-DioK using dioxins standard samples.

Analysis of Pesticides in Spinach Purchased from Local Grocers Using Triple-Quadrupole GC-MS/MS Analysis