Determination of heterocyclic aromatic amines in beefburguers by using microwave-assisted extraction (MASE) and dispersive liquid-ionic liquid microextraction (DLILME). Optimization of the DLILME by using a central composite design procedure

AGUDELO MESA, LEIDY B.; PADRÓ, JUAN M.; RETA, MARIO

Amsterdam

Simposio; 39th International Symposium on High-Performance-Liquid-Phase Separations and Related Techniques; 2013

International Separation Science Society

Heterocyclic aromatic amines (HAAs) are mutagenic and/or carcinogenic compounds formed during the cooking process at high temperatures of protein-rich foods. The concentration increases with temperature and cooking time, among other factors. The analysis of HAAs is difficult because of the matrix complexity, which involves the use of extensive and laborious procedures for sample preparation and because of the low concentration levels they are present. The extraction of HAAs from food products is normally carried out by solid phase extraction (SPE) in various stages. In this work we developed a simple, rapid and cheap sample pretreatment method for the analysis of non-polar HAAs in cooked beefburguers by using microwave-assisted solvent extraction (MASE) combined with dispersive liquid-ionic liquid microextraction (DLILME) using an ionic liquid generated in-situ. A final HPLC-DAD-FLD technique for the qualitative and quantitative analysis was used. The sample is first cleaned with heptane in the MASE oven and then, extracted with a basic solution previous to the DLILME procedure. According to a prvious work, three significant variables were selected to define the experimental field for the DLILME: volume of ionic liquid, volume of disperser solvent and pH. Ionic strength has no effect on extraction efficiency. In a second set of experiments, a central composite design (CCD) procedure for optimizing the significant variables was used. Mathematical models able to describe the system and to find the optimal conditions for the analysis were applied. The optimized procedure was used for the analysis of HAAs in commercial beefburguers of different brands, cooked both in oven and pan. Repeatability (RSD%) between 5 and 10%, enrichment factors between 19 and 30, limits of detection between 0.35-2.4 ng mL-1 and recoveries between 69 and 100% were achieved. Thus, the technique has similar or better figures of merit than previously reported methodologies.