Use of SFC/MS for the confirmation of peak identities in the SFC/FID chromatogram of olestra

Abstract

AbstractOpen tubular supercritical fluid chromatography (SFC) with flame ionization detection (FID) has been used for characterizing olestra, a mixture of fatty acid sucrose esters. In this publication, we describe SFC/mass spectrometry (SFC/MS) of olestra using the direct fluid introduction interface. Chemical ionization spectra were used in confirming SFC/FID peak identities. Electron ionization SFC/MS of olestra was also investigated. Both major and minor component peaks in the SFC chromatogram of olestra were characterized. A slight modification of the interface‐probe tip was necessary for operation at higher temperature. A procedure was developed for tuning and calibrating the instrument in the 10‐4000‐u mass range, chemical ionization mode using Ultramark 3200, a perfluorinated polyether. The use of additional pumping in the form of liquid nitrogen cooled cryopumps was key in providing good signal‐to‐noise ratios for the latereluting (i.e., eluting at higher mobile phase pressures and flow rates) olestra components.