Sample Preparation Improvement in Polycyclic Aromatic Hydrocarbons Determination in Olive Oils by Gel Permeation Chromatography and Liquid Chromatography with Fluorescence Detection

Abstract

The determination of 15 polycyclic aromatic hydrocarbons (PAHs) in olive oil samples has been improved in order to obtain a fast methodology with a low limit of detection through the combination of liquid–liquid extraction with acetonitrile and preparative gel permeation chromatography (GPC) prior to the injection of purified extracts into a C18 column. Acetonitrile–water was used as the mobile phase with a gradient from 50 to 95%, w/w, acetonitrile in 30 min. The oven temperature was maintained at 15°C, and fluorometric detection was made at a fixed excitation wavelength of 264 nm and variable, optimal emission wavelength for each analyte ranging from 352 nm for 11-H-benzo(b)fluorene to 500 nm for indeno(1,2,3-cd)pyrene. Recovery for all the compounds studied varied from 75 to 111%, and limit of detection values from 0.05 ng/g for benzo(k)fluoranthene to 0.48 ng/g for indeno(1,2,3-cd)pyrene, corresponding to 0.09 ng/g benzo(a)pyrene. Results were compared with those obtained by liquid–liquid extraction followed by a cleanup on silica and a direct GPC treatment of oil samples diluted in dichloromethane, 2 other methodologies that are appropriate for quantifying PAHs in olive oils. However, the proposed method improves the determination limits, reduces the time of analysis, and provides a highly stable baseline for sample chromatograms.

Detection, Risk Assessment, and Survey of Four Polycyclic Aromatic Hydrocarbon Markers in Infant Formula Powder

“…To improve the sample preparation method, several studies have been conducted to investigate extraction and purification methods for PAH analysis in different foods. Marinez-Lopez et al [16] improved the determination efficiency of 15 PAHs in olive oil samples through liquidliquid extraction and preparative gel permeation chromatography (GPC) purification before analysis. Fromberg et al [17] presented a semi-automatic method for the determination of PAHs in edible oils using a combined gel permeation chromatography/solid-phase extraction (GPC/ SPE) clean-up.…”

Feasibility of the determination of polycyclic aromatic hydrocarbons in edible oils via unfolded partial least-squares/residual bilinearization and parallel factor analysis of fluorescence excitation emission matrices

“…Although the LOD for these analytes are in the order of 2.0 μg kg -1 , it can be acceptable for its determination in potentially contaminated samples. Moreover, the LODs obtained by U-PLS/RBL are in the order of those reported for HPLC-FLD methods [2,4,7,9,35]. Although LODs obtained with PARAFAC were bellow 2.0 μg kg -1 for BaA, BbF, BkF and DBahA, they were almost 2 or 3 times higher than those obtained by U-PLS/RBL.…”

“…These compounds are mostly formed by incomplete combustion of organic matter being continuously released into the atmosphere from natural and anthropogenic sources [2][3][4].…”

Polycyclic aromatic hydrocarbons in edible oils: An overview on sample preparation, determination strategies, and relative abundance of prevalent compounds

“…The optimum separation conditions usually imply a solvent gradient with ACN and water. Gradients normally start with a 40% to 50% ACN, in most cases (Barranco et al, 2003;Costopoulou et al, 2010;Gharbi et al, 2017;Martinez-López et al, 2005;Payanan et al, 2013;Shi et al, 2015Shi et al, , 2018Stenerson et al, 2015;Taghvaee et al, 2016;Teixeira et al, 2007;Yousefi et al, 2018;Zhao et al, 2013); then this concentration is linearly risen to 89% to 100% in an approximate time of 45 min, as so suggests ISO 15753:2016. Some reports have indicated the use of gradients with a higher proportion of ACN (70% to 85%) at the beginning of the run (Alves da Silva et al, 2017;Camargo et al, 2011;Ergönül & Sánchez, 2013;Ji et al, 2017;Molle et al, 2017;Moreda et al, 2004;Purcaro et al, 2008;Rodríguez-Acuña et al, 2008a;Tfouni et al, 2014).…”

“…Several techniques have been applied to that end. GPC has proved to be very efficient to remove fatty interferences (Ballesteros, García‐Sánchez, & Ramos‐Martos, 2006; Bordajandi, Dabrio, Ulberth, & Emons, 2008; Ciecierska & Obiedziński, 2013; Fromberg, Højgård, & Duedahl‐Olesen, 2007; Gómez‐Ruiz & Wenzl, 2009; Martinez‐López, Morales‐Noé, Pastor‐Garcia, Morales‐Rubio, & De La Guardia, 2005; Wang & Guo, 2010), due to the substantial difference between TAGs and PAHs molecular size. This allows a first elution of lipidic substances and a successive elution of the analytes of interest.…”