Peak asymmetry in gas-liquid chromatography caused by adsorption exchange between the molecules of the sorbate and the stationary liquid phase

1977 ◽  
Vol 10 (9) ◽  
pp. 532-536 ◽  
Author(s):  
A. N. Genkin ◽  
N. S. Levina
Keyword(s):  
Liquid Chromatography ◽  
Liquid Phase ◽  
Gas Liquid Chromatography ◽  
Stationary Liquid Phase ◽  
Stationary Liquid ◽  
Peak Asymmetry

THE SEPARATION OF SOME TERPENOID COMPOUNDS BY GAS–LIQUID CHROMATOGRAPHY

1960 ◽  
Vol 38 (5) ◽  
pp. 631-640 ◽  
Author(s):  
E. von Rudloff
Keyword(s):  
Liquid Chromatography ◽  
Polyethylene Glycol ◽  
Liquid Phase ◽  
Diatomaceous Earth ◽  
Solid Support ◽  
Gas Liquid Chromatography ◽  
Polyphenyl Ether ◽  
Liquid Phases ◽  
Degree Of Separation ◽  
Separation Of Mixtures

A study has been made of the degree of separation of mixtures of some terpene hydrocarbons, some of their oxygenated derivatives, two sesquiterpene alcohols, and three monophenols on a variety of columns. Temperature and sample size affected the degree of separation and the solid support Chromosorb W, a calcined diatomaceous earth, was found to combine the advantages of Celite and C-22 firebrick without causing decomposition of the sample at higher temperatures. When Craig polyesters were used as liquid phases, separations equal to those obtained on polyethylene glycol were realized with the added advantage that these produced columns which are stable at 190 to 220 °C. Consequently, sesquiterpene alcohols and monophenols were also separated successfully. Another useful liquid phase for both low and high temperatures was found in a meta-linked polyphenyl ether. Squalene was found to be an efficient liquid phase for the separation of terpene hydrocarbons at 130 °C and lower. The possible application of the present findings for preparative work is discussed.

Gas—Liquid Chromatographic Measurement of Guanidino Acids

1975 ◽  
Vol 21 (7) ◽  
pp. 838-843 ◽  
Author(s):  
Harini Patel ◽  
Burton D Cohen
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Liquid Chromatography ◽  
Liquid Phase ◽  
Magnetic Resonance ◽  
Gas Liquid Chromatography ◽  
Butyl Esters ◽  
Silicone Liquid ◽  
Chromatographic Measurement ◽  
Liquid Chromatographic

Abstract We present a method for separating and measuring guanidino acids by gas—liquid chromatography. Compared to ion-exchange techniques, this system is faster, more sensitive, requires smaller sample volumes, is independent of colorimetric reactions, and permits simultaneous determination of both amino and guanidino acids. N-Trifluoroacetyl-n-butyl esters are formed and then are separated by using a column containing a mixed silicone liquid phase coated on Chromosorb W-HP. Analytical recoveries from plasma ranged from 86 to 112% and were optimal when purification and derivatization were done without prior protein precipitation. Speculations as to the cause of this interference by protein include coprecipitation, protein-binding, and cyclization of the guanidines in the acids used for denaturation. Evidence presented suggests that all three occur: ultrafiltrability is diminished in the presence of protein and nuclear magnetic resonance demonstrates cyclization of some of these esters.

Sign in / Sign up

Export Citation Format

Share Document