Determination of Heterocyclic Aromatic Amines in Various Fried Food by HPLC–MS/MS Based on Magnetic Cation-Exchange Resins

The heterocyclic aromatic amines (HAAs) in the food matrix were extracted and purified by prepared magnetic cation-exchange resin (MCER) for the first time. The Fourier transform infrared spectroscopy and vibrating sample magnetometer analysis indicated that MCER was successfully synthesized and exhibited superparamagnetism. Under the optimized adsorption and analytical conditions, the MCER could effectively enrich HAAs (Trp-P-2, IQx, IQ, MeIQ, 4,8-DiMeIQx, 7,8-DiMeIQx, AαC, MeAαC, norharman) from food samples with excellent linearities (0.9956–0.9995), extremely low limit of detections (0.028–0.225 ng g−1), and relatively satisfactory precisions (2.39–11.04%), and recoveries (63.59–111.33%). In addition, compared with traditional solid-phase extraction, the current magnetic solid-phase microextraction method has the advantages of simpler sample processing procedure and lower cost. Moreover, compared with the existing magnetic adsorbents, the prepared MCER used in our method could be successfully prepared under mild conditions. Finally, the established method was advantageously applied to the determination of HAAs in fried foods under deep-fat frying and hot-air frying with different frying times and temperatures. Besides, principal component analysis, partial least-squares discriminant analysis, and variable importance in projection value were applied, and the results showed that the concentration of HAAs in fried food was affected by the processing methods, processing time, and frying temperatures, thereby affecting the quality of the food. Therefore, this method can be substituted for traditional analysis methods to ensure the sanitation and quality of the processed food.