HPLC-NMR of fatty alcohol ethoxylates.
The application of HPLC-NMR for the analysis of a mixture of fatty alcohol ethoxylates (FAEs) is described. The use of the new generation, cryogenically cooled probes is investigated in respect of the sensitivity advantage that they provide. The FAE mixture is separated using liquid chromatography at the critical point of adsorption. The ability of the method to differentiate between the different end groups and the degree of polymerization of the mixture constituents is investigated. Both on-flow and stop-flow HPLC-NMR techniques were used together with two-dimensional NMR spectroscopy. The results are compared with those obtained by using an evaporative light scattering detector for the HPLC.
Hiller
Wolf
W
Varian Deutschland GmbH, Darmstadt, Germany. whiller@dki.tu-darmstadt.de
Brüll
Adele
A
Argyropoulos
Dimitris
D
Hoffmann
Eberhard
E
Pasch
Harald
H
D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005027:Ethylene Oxide / Q000737:chemistry; D005233:Fatty Alcohols / Q000032:analysis*; D007553:Isotope Labeling; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D011108:Polymers / Q000737:chemistry; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods
D005233:Fatty Alcohols; D011108:Polymers; D005027:Ethylene Oxide