Gas-liquid chromatography of saturated fluorinated carboxylic acid esters 1. Retention in homologous series

Author(s):  
E. P. Promyshlennikova ◽  
V. E. Kirichenko ◽  
K. I. Pashkevich ◽  
D. N. Grigor'eva ◽  
R. V. Golovnya
1982 ◽  
Vol 65 (1) ◽  
pp. 66-70 ◽  
Author(s):  
Martin J Lynch ◽  
S Richard Bartolucci

Abstract A confirmatory method has been developed to identify quinoxaline-2-carboxylic acid, the carbadox tissue residue, in swine liver, a target tissue, at the regulatory level of 30 μg/kg. Quinoxaline-2-carboxylic acid (QCA) is isolated from liver hydrolysates by solvent extraction and ion-exclusion chromatography, and a methyl ester derivative (CP-25,536 or QME) is identified by gas-liquid chromatography/ mass spectrometry with selected ion monitoring. The relative intensities of 3 ions: the base peak at m/z = 130, a second significant mass at m/z = 158, and the molecular ion (M+) at m/z = 188, are monitored simultaneously with a quadrupole mass spectrometer. Validation studies consisting of the analysis of liver fortified with QCA at the regulatory level and analysis of swine specimens containing physiologically incurred carbadox residues demonstrated that peak height ratios of ions in these tissue extracts corresponded to ion intensities of standards monitored at m/z = 188,158, and 130.


1962 ◽  
Vol 40 (6) ◽  
pp. 1118-1122 ◽  
Author(s):  
N. Narasimhachari ◽  
E. Von Rudloff

The wood of the showy mountain ash was found to contain about 3% acetone-soluble material. The major constituents of the extract were a polymorphous xyloside of (+)-di-methoxyisolariciresinol, the recently discovered hydroxy diphenyls aucuparin and methoxyaucuparin, and fatty acid esters of β-sitosterol, another phytosterol, and of untractable phenolic material. Small amounts of free β-sitosterol and a mixture of hydrocarbons as well as traces of an unknown leucoanthocyanidin were also isolated. The xyloside predominated in the sapwood, whereas the aucuparins were found mainly in the heartwood. Gas–liquid chromatography was instrumental in the detection and separation of the aucuparins.


1963 ◽  
Vol 17 ◽  
pp. 1828-1830 ◽  
Author(s):  
Torbjörn Norin ◽  
Lars Westfelt ◽  
Erling Røst ◽  
Arne Steffensen ◽  
Jon Munch-Petersen

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