|Analysis of Dithiocarbamate Pesticides by GC-MS|
Soma Dasgupta1,2, Sumaiyya Mujawar1, Kaushik Banerjee1, Hans-Joachim Huebschmann3, Paul Silcock4
Analysis of dithiocarbamate pesticides (DTCs) using an optimized GC-MS method is described. DTCs are not stable and cannot be extracted or analyzed directly. The purpose of this work was develop a reliable method for identification and quantification of residues.
|Analysis of Multiresidue Pesticides Present in Ayurvedic Churna by GC-MS/MS|
Manoj Surwade, Sunil T Kumar, Aarti Karkhanis, Manish Kumar, Soma Dasgupta, Hans-Joachim Huebschmann, Paul Silcock, Thermo Fisher Scientific
Analysis of Herbal powders or ‘churnas’ using an optimized GC-MS/MS method is described. As they have high amount of matrix co-extractives, they pose critical analytical problems. The purpose of this work was overcome the effect of the matrix and develop a reliable method.
|Automated Solid-Phase Extraction of Oraganochlorine Pesticides from Drinking Water|
Frans Schoustsen and Pranathi R Perati
A new method was developed to automate the capture and elution of Organochlorine pesticides from drinking water. The concentrated analytes were then analyzed by GC with Electron Capture Detection (ECD).
|GC-MS/MS Analysis of Pesticide Residue in Green Tea Extracted by QuEChERS with Acetonitrile as Final Solvent|
Cojocariu C., Morgan P., Silcock P., Godula M
QuEChERS involves an initial step when a few grams of the sample are extracted with acetonitrile followed by a clean-up step (with dispersive-SPE) used to remove, to a certain extent, unwanted matrix compound (such as pigments, sugars, organic acids). With QuEChERS, the final extract ends up with the pesticides in acetonitrile, which, being polar solvent, can be
problematic in GC-MS.
|Increasing Extraction Efficiency of Pesticides and Dioxins from Wet Samples Using a Novel Polymer During Accelerated Solvent Extraction|
Katerina Bousova, Pranathi Perati, Rahmat Ullah, Kannan Srinivasan
Thermo Scientific™ Dionex™ ASE™ Prep MAP is a proprietary polymer designed to remove moisture and increase extraction efficiencies from wet samples including soils, tissues and food products. This unique formulation allows moisture removal under a variety of ionic strength conditions and accelerated solvent extraction conditions.
|Identifying Unknown Chemicals and Disinfection Byproducts in Swimming Pools and Hot Tubs|
Jonathan D. Byer, Susan D. Richardson, Eric J. Daiber, Sridevi Anduri Chowdary, Joe Binkley, Jeff Patrick
DBPs were identified in finished water, tap water, swimming pool water, and hot tub water that were not present in the source water. High Resolution Deconvolution was used effectively to identify a greater number of peaks in the chromatogram than by nominal resolution MS.
|Strategic Utilization of Gas Chromatography with Both Nominal and High Resolution Time-of-Flight Mass Spectrometers for Metabolomic Studies|
David E. Alonso, Jeff Patrick, and Joe Binkley
The Pegasus series of mass spectrometers are indispensable tools for metabolomics research:
GC-HRT analyses resulted in confident metabolite identifications:
-Spectral similarity searches
-Formulae for fragment, molecular, and adduct ions
|Post-Target Analysis of Halogenated Flame Retardants Using Mass Defect Plots|
Jonathan D. Byer, Grazina Pacepavicius, Mehran Alaee, Karl Jobst, and Joe Binkley
A number of legacy contaminants and other pesticides were identified in the pooled sample. Cl-H mass defect plots are a useful tool for filtering through complex data for the identification of halogenated contaminants. This technique functions as a screening tool for the identification of unknowns, and in the future, may be used as a form of fingerprinting to compare samples.
|Myth Busters: The Truth About Metabolomics and High Resolution Gas Chromatography Time-of-Flight Mass Spectrometry|
David E. Alonso, Joe Binkley, and Lorne Fell
The data summarized in this presentation dispels myths associated with the utilization of GC-MS for analytes which are critical for metabolomic studies. GC-HRT provides high quality, accurate mass data for:
-Spectral similarity searches (NIST, Wiley, etc.)
-Formula determination (fragment, molecular & adduct ions)
-GC-HRT is an indispensible tool for the analysis of complex biological samples.