Analysis of free and esterified sterols in edible oils by online reversed phase liquid chromatography–gas chromatography (RPLC–GC) using the through oven transfer adsorption desorption (TOTAD) interface

New Analytical Method for Determination of Phthalates in Wastewater by on Line LC-GC-MS Using the TOTAD Interface and Fraction Collector

“…Even though on line LC-GC is more difficult when the LC step is carried out in reversed phase (RPLC-GC) rather than in normal phase (NPLC-GC), we decided to use acetonitrile/water as LC eluent due to the aqueous nature of the sample. It should be noted that, unlike other interfaces, the TOTAD interface has demonstrated its suitability for on line NPLC-GC as well RPLC-GC [52,53]. A solution of each phthalate in acetonitrile at 10 mg/L was used to set up the LC fractions to be transferred to the GC.…”

Characterization and authentication of four important edible oils using free phytosterol profiles established by GC-GC-TOF/MS

“…By using GC-GC, better separation of these TMS-sterols could be achieved compared to a single fused-silica column (30 m  0.25 mm I.D.  0.25 mm lm thickness) coated with 5% phenyl methyl silicone as reported by Toledano et al, 34 and better separation could also be obtained in the region of TMS-24-methylene-cholesterol, TMS-campesterol, and TMS-campestanol compared to a single 50 m SE-54 column (0.25 mm I.D.  0.10 mm lm thickness) reported in ISO 12228:1999.…”

“…30 In contrast, the complete information regarding free sterols' distributions and concentrations in edible oils is rare. Investigation on free sterols in edible oils are commonly based on the isolation of this type of compound by solid phase extraction (SPE) [31][32][33] or preparative online/offline liquid chromatography (LC) 34,35 and analysis by means of GC-FID, 31 GC-MS, 32,33 or reversed-phase high-performance liquid chromatography equipped with an evaporative light-scattering detector (RP-HPLC-ELSD). 25 Using these approaches, free sterols were determined in several edible oils.…”

In-House Validation of an SPE-GC-FID Method for the Detection of Free and Esterified Hydroxylated Minor Compounds in Virgin Olive Oils

“…To date, there is no validated method that can be used for assessment of free and esterified HMCs in EVOO. In addition to this crucial aspect, previously published methods also had critical analytical aspects such as the requirement for saponification of the purified free and esterified fractions [24][25][26], a long preparative glass column employing significant amount of silica and solvents, and complex chromatographic approaches such as online LC × GC, demanding dedicated instrumentation and skilled operators [22,[27][28][29][30][31].…”