OH‐terminated cyanopropyl silicones

Abstract

Due to their high polarity and unique selectivity, cyanopropyl silicones are basic stationary phases for high resolution capillary gas chromatography. Different OH-terminated cyanopropyl silicones, containing a high cyanopropyl content, were synthesized and chromatographically evaluated. Special attention was paid to the degree of immobilization of the phases in FSOT columns. Depending on the problem at hand, a choice has to be made between immobilization and maximum selectivity.

Evaluation of ionic liquid stationary phases for one dimensional gas chromatography–mass spectrometry and comprehensive two dimensional gas chromatographic analyses of fatty acids in marine biota

“…On the SLB-IL 82, C18:3n6 elutes before C20:0, on the HP-88 C18:3n6 and C20:0 partly overlap and on the SLB-100 C18:3n6 Calculated by interpolation using bracketing linear saturated fatty acid methyl esters, with C15:0 = 15.00, C16:0 = 16.00, etc., using ECL = (tR i − tRn)/(tRn+1 − tRn) + n. elutes after C20:0. This solute pair was previously used for the characterization of highly polar cyanopropyl stationary phase [41]. The value obtained for C20:1n9 (ECL = 20.62) (here, using a temperature gradient) corresponds well with the data reported by Ando and Sasaki (ECL = 20.57-20.73, depending on isothermal temperature) [35].…”

Analysis of free fatty acids and fatty acid phenacyl esters in vegetable oils and margarine by capillary electrochromatography

“…CGC, however, fails to separate all cis-trans isomers in a particular carbon number. The elucidation of the cis/trans ratio fo 18:1 in margarines by CGC is therefore less accurate than by CEC [13]. Free fatty acids can also be analyzed by CEC on nitroterephthalic acid-derivatized polyethylene glycol stationary phases but this method is hardly applicable because of its poor ruggedness for routine work.…”

Dicyanobiphenyl polysioloxane stationary phases for capillary column gas chromatography

“…Slower solute diffusion in the cyanoalkylpolysiloxanes causes efficiency losses [8]. Hydroxyterminated stationary phases [9,10] possess higher thermal stabilities, but their efficiencies are moderate, and their applications are mainly limited to high temperature GC. Present-day capillary column gas chromatography practice shows that stationary phases other than the polymethylsiloxanes are suitable only for certain types of separation problems.…”