Analysis of complex mixtures of polyglycerol fatty esters using liquid chromatography and high-resolution mass spectrometry: Retention, structural and relative composition study

Abstract

Polyglycerol esters (PGEs), produced by esterification of fatty acids on polyglycerols, were analysed by High Resolution Mass Spectrometry (HRMS), HPLC-MS and U-HPLC-MS. A structural study of PGEs in 4 samples synthesised by the Gattefossé company was carried out using an elemental analysis of HRMS spectra and modelling of all probable isomers and cyclic structures. The results were used to construct a structural database of all species present in the 4 samples. After an assessment of the selectivity of 5 reversed phase columns: Aeris Widepore XB-C8, 3.6µm, 2.1x150 mm (Phenomenex), Acquity CSH C18 1.7µm 2.1x50mm, Acquity CSH Phenyl-Hexyl 1.7µm 2.1x50 mm, Acquity CSH Fluoro-Phenyl 1.7µm 2.1x50mm (Waters Co.) and Kinetex F5 1.7µm 2.1x100mm (Phenomenex), HPLC-MS and U-HPLC-MS analyses were performed on an Aeris Widepore XB-C8 (Phenomenex) column (HPLC) and Acquity CSH Fluoro-Phenyl (Waters) column (U-HPLC) with aqueous formic acid /acetonitrile in Highlights  Batch comparisons and quantification of constituents of complex formulations  Structural database construction with HRMS spectra and modelling of all probable PGEs

Analytics and applications of polyglycerol polyricinoleate (PGPR)—Current research progress

“…However, recently, Garrigues et al. (2020) developed a semiquantitative method for the molecular constituents of polyglycerol fatty acid esters by using high resolution mass spectrometry (HRMS), HPLC‐MS, and U‐HPLC‐MS. Nevertheless, the techniques applied in that study failed for the absolute quantification of these constituents.…”

A rapid and sensitive method for characterization and quantification of polyglycerol esters by supercritical fluid chromatography coupled to high-resolution mass spectrometry (SFC-HRMS)

“…When polyglycerol oligomers are available, PGEs could be directly formed by mixing them with fatty acids. The final product is very complex with various compounds different in the degree of polymerization, the branching type of oligomers, the number and the length of fatty acids [6]. Therefore, a method for the PGE qualification and/or quantification would be necessary to optimize the synthesis process.…”

“…Thus, no absolute quantitative method for PGEs has been described yet in the literature. Some studies about PGE analysis methods have been published by using thin-layer chromatography (TLC) [8], gas chromatography (GC) [9], high-performance liquid chromatography HPLC [6,7,10], GC combined to LC [11], supercritical fluid chromatography (SFC) [12] with mass spectrometry (MS) [6,7,[9][10][11], evaporative light scattering detection (ELSD) [7], or flame ionization detector (FID) [12]. Recently, a (U)-HPLC-MS method for relative PGE quantification has been developed but without taking into account the difference in ionization yields of PGEs depending on their structures [6].…”