|Minimizing Carry-over for High Throughput Analysis|
Christian Berchtold1, Reto Bolliger2, Guenter Boehm2, Götz Schlotterbeck1
Minimal carry-over is a prerequisite for high throughput analysis. However, minimized carry-over and cycle time are competing and a careful optimization is mandatory. In this study the influence of wash conditions on carry-over of various compounds was investigated. A strategy to minimize carry-over was developed. The influences of different wash tasks were investigated. Finally the contribution of different system components such as injector valve or column was studied.
|A Comparison of ITEX Dynamic Headspace–GC/MS to other Enrichment Techniques for Analysis of Flavoring Compounds|
Douglas Doster1; Roger Pearson1; Sean Eppel1; Ken Rice1; Tom Flug2; Brian Peat2; Guenter Boehm2
Enrichment techniques are commonly used for the analysis of flavoring compounds in different matrices with GC/MS. Analysis of flavoring compounds is done by purge & trap, SPME or headspace, depending on requirements for sensitivity. The In-Tube Ex¬traction (ITEX) Dynamic Headspace uses a micro trap filled with an adsorbent material to efficiently extract the compounds. Here we evaluate if the ITEX can be used to effectively analyze for these compounds and reduce the analyst’s time involved.
|Optimization of a Vacuum Ultraviolet Photoionization source for Gas Chromatography used with a High Resolution Time of Flight Mass Spectrometer|
Lloyd Allen and Viatcheslav Artaev
-Tune solution allows optimization of ion source parameters for
both proton transfer and direct ionization
-Independent ionization processes exist for M+ and MH+
-Optimizing for dopant signal intensity yields inferior results
-Degree of fragmentation remains relatively constant over a
range of source conditions
|High Performance Comprehensive Two-Dimensional Gas Chromatography Coupled with a High Resolution Multi-Reflecting TOFMS for Confident Non-Target Analyte Identification|
Scott J. Pugh, Viatcheslav Artaev, Mark F. Merrick, Jack Cochran
The use of comprehensive two-dimensional gas chromatography to help increase chromatographic resolution is a major step in tackling the problem of confident peak identification in a complex sample matrix. Combining the separation power of two-dimensional gas chromatography, with resolving power greater than 25,000, and sub ppm mass accuracies of a high resolution multi-reflecting TOFMS is the ideal solution to confident compound identification within a complex sample matrix.
|Fragmentation Trees for Automated de novo Interpretation of Impure Electron Ionization Spectra from Gas Chromatographic Complex Mixture Analysis—Chemical Deconvolution|
Kevin Siek, Vasily Makarov, Viatcheslav Artaev, Dmitry Mazur, Albert T. Lebedev
-Chemical deconvolution algorithms accurately reported independent
components of dead coelutions where such components belong to distinct chemical classes.
-Present algorithms fail to distinguish chemically similar analytes such as branched and linear alkanes, thus chemical deconvolution is not a
substitute for GCxGC.
-Chemical deconvolution algorithms accurately rejected more than 80% of spurious signals from manually curated spectra found to be contaminated with unrelated signa
|Effective Comparison of Yeast Extracts Using High Resolution GC and GCxGC-HRTOFMS|
David E. Alonso and Joe Binkley
The Pegasus GC-HRT and GC-HRT 4D instruments are effective tools for the comprehensive analysis of yeast extracts.
• Enhanced chromatographic resolution of the HRT 4D system facilitated compound characterization by improving spectral similarity scores
• High quality data resulted in excellent spectral similarity scores when compared to large, well-established databases (NIST, Wiley)
• High resolution, accurate mass data was crucial for determination of fragment, molecular, and adduct
|Performance Characteristics of a Comprehensive Two=Dimensional Gas Chromatography-High Resolution Time-of=Flight Mass Spectrometry System (GCxGC=HRTOFMS) Utilizing Chemical Ionization|
Jonelle Shiel, Mark Merrick, Scott Pugh, Matthew Soyk, and Viatcheslav Artaev
Combining comprehensive two-dimensional gas chromatography (GC×GC) with a High Resolution Time-of-Flight Mass Spectrometer and Chemical Ionization is a powerful tool for compound identification. Performance of the LECO Pegasus GC-HRT 4D using Chemical Ionization (CI) was demonstrated using Benzophenone and Diesel. GC×GC separation results in narrow peaks, therefore, a high speed detection system is necessary.
|Non-Target Analysis of Electronic Waste Samples from China|
Jonathan D. Byer, Ed Sverko, Kurunthachalam Kannan, Qian Wu, Joe Binkley
GC×GC-HRT is a powerful tool for the comprehensive analysis and
chemical characterization of analytes in complex matrices. The combination of high resolution front-end separation with high
resolution time-of-flight mass spectrometry made possible the
identification of compounds previously unknown in these samples.
|Spice Wars- Are You Battle Ready? Analysis of Synthetic Cannabinoids via Gas Chromatography—High Resolution Time-of-Flight Mass Spectrometry|
David E. Alonso, John Rorabeck, and Joe Binkley
-EI/CI workflow facilitates confident compound identification.
-GC-HRT and HR-CI source provides high quality, accurate mass data for:
-Database searches (NIST, Wiley, etc.)
-Formula determination (fragment, molecular, and adduct ions)
|A proteomic analysis of p27kip1-binding proteins reveals a putative role in transcription regulation through RNA polymerase II interaction|
Juan Triviño Paredes1, Atilla Biçer1, Arnauld Besson2, Edurne Gallastegui1, Josep Maria Estanyol3, Maria Jesus Pujol1 and Oriol Bachs1
A proteomic analysis of p27kip1-binding proteins reveals a putative role in transcription regulation through RNA polymerase II interaction
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