Adjustable open-split interface for gas chromatography/mass spectrometry providing solvent diversion and invariant ion source pressure

1991 ◽  
Vol 63 (20) ◽  
pp. 2386-2390 ◽  
Author(s):  
Woodfin V. Ligon ◽  
Hans. Grade
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Ion Source ◽  
Gas Chromatography Mass Spectrometry ◽  
Source Pressure ◽  
Chromatography Mass Spectrometry

APPLICATION OF COMPUTERIZED GAS CHROMATOGRAPHY – MASS SPECTROMETRY TO OIL EXPLORATION IN AUSTRALIA

1980 ◽  
Vol 20 (1) ◽  
pp. 221 ◽  
Author(s):  
R.P. Philp ◽  
T.D. Gilbert
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Crude Oil ◽  
Biological Marker ◽  
Ion Source ◽  
Gas Chromatography Mass Spectrometry ◽  
Analytical Technique ◽  
Chromatography Mass Spectrometry ◽  
Ms Analysis ◽  
The Masses

Computerized gas chromatography-mass spectrometry (C-GC-MS) is a sophisticated analytical technique capable of identifying very small quantities of individual components in complex mixtures of organic compounds. One field in which C-GC-MS can play an extremely important role is correlation studies of crude oils and source rocks.In C-GC-MS analyses, compounds present in the crude oil or source rock extract are first separated by the gas chromatograph and then fragmented and ionized in the ion source of the mass spectrometer. The mass and relative intensities of the ions formed are recorded by the computer. Normally the masses of one or two specific fragments can be used to distinguish as particular class of compounds, a technique that is particularly useful for crude oil correlation studies.Comparison of mass fragmentograms for different oils yields information about their sources. Identical fragmentograms for ion characteristics of certain classes of "biological marker" compounds imply that the distribution of compounds in the oils is identical and hence that the oils had the same or very similar sources.Results of C-GC-MS analysis of four oils from the Gippsland Basin indicate that, despite varying degrees of biodegradation, the oils had the same or very similar source materials. Similarly C-GC-MS analysis of the Barrow Jurassic and Windalia oils from the Carnarvon Basin provides evidence to support the theory that these two oils had the same or very similar source material.

Identification of a synthetic cannabinoid 5F-NPB-22 (indazole analog 5F-PB-22) by gas chromatography/mass spectrometry (GC/MS) method

2016 ◽  
Vol 293 ◽  
pp. 56-67
Author(s):  
Robert Bachliński ◽  
◽  
Agnieszka Mroczek ◽  
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Direct Injection ◽  
Ion Source ◽  
Synthetic Cannabinoid ◽  
Gas Chromatography Mass Spectrometry ◽  
Extraction Solvent ◽  
Chromatography Mass Spectrometry ◽  
Selection Of

This article presents the problem of transesterification of a synthetic cannabinoid 5F-NPB-22 and other structurally related indazole and indole-based compounds, such as NPB-22, 5F-PB-22, BB-22 and PB-22, caused by methanol – a solvent commonly applied in gas chromatography/mass spectrometry (GC/MS) analysis. The above process can result in drawing incorrect conclusions about the composition of analyzed product, due to the formation of ester compounds, which mainly affects the reliability of results. In the present study, in addition to the mixture of methanol and toluene, as well toluene alone was used to evaluate the effect of both these solvents on the results obtained with GC/MS. The quality of analyses was additionally confirmed by quadrupole-time-of-flight (Q-TOF) mass spectrometry with direct injection of sample into the ion source. The final results indicate that in the case of transesterification-sensitive compounds, the selection of an adequate extraction-solvent is of major importance. It is recommended to use toluene and exclude transesterification-supporting solvents such as low molecular weight alcohols (methanol.ethanol). Moreover, a prompt analysis of the extracted substances should be ensured in order to eliminate their potential esterification.

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