AFFINILUTE™ MIP - PAH

Selective SPE sorbent for extraction of polycyclic PAHs from organic matrices

A selective SPE sorbent for extraction of high cycle PAHs from organic matrices Polyaromatic hydrocarbons (PAHs), many of which are carcinogenic, consist of fused aromatic rings and are formed as by-products during combustion. Seven carcinogenic PAHs are closely monitored in both environmental samples and food; benz[a]anthracene, benzo[a]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, chrysene, dibenz[a,h]anthracene, and indeno[1,2,3-cd]pyrene.

One of the most potent PAH's, benzo[a]pyrene, is found in a number of edible oils (olive, grapeseed, pomace, etc.) and is generated during the production process of such oils. For example, the use of contaminated solvents during olive mash extraction and extensive heat treatment during solvent evaporation, have been attributed as causes of PAH contamination.

In 2005, the European Union set maximum limits of PAHs in food. For example, in oils and fats intended for direct human consumption, the maximum residue limit, based on benzo(a)pyrene levels measured on wet weight, is 2 µg/kg (Maximum levels of PAHs in food.doc) Further, new regulations on levels of PAHs in ‘extended fuels’, also governed by EU Regulation 2008/2005, came into effect Jan 1, 2010

Features and Applications
An effective SPE method has been determined for PAHs and can be further optimized for a number of matrices. The PAHs that have been tested include: fluoranthene, benzo[a]anthracene, chrysene, benzo[k]fluoranthene, benzo[b]fluoranthene, benzo(a)pyrene, indenol[1,2,3-cd]pyrene, dibenzo[a,h]anthracene and benzo[ghi]perylene. AFFINILUTE MIP - PAH is not suitable for extracting smaller PAH compounds (2-3 rings) or for quantitative extraction of pyrene.

Two procedures have been developed. The first is a general procedure using non-polar organic solvents such as cyclohexane to extract the PAHs with subsequent clean-up on the AFFINILUTE MIP - PAH column and analysis by GC/MS. This general procedure represents a recommended starting point for further optimization.

In addition, a method specific for measurement of PAHs in olive oil is available. This procedure gives high recoveries (average recovery of 78% for 9 different PAHs) and high sensitivity (0.2 ppb for benzo(a)pyrene and 0.02 ppb for benzo[a]anthracene).