<strong>Development of a novel molecularly imprinted stir-bar for isolation of aflatoxins</strong>

Abstract

Mycotoxins are natural compounds produced as secondary metabolites by a wide variety of different species of filamentous fungi. One of the most important groups in terms of occurrence and toxicity is the group of aflatoxins (AFs). The major members of this group are aflatoxin B1, B2, G1, G2, M1 and M2. Exposure to AFs can cause chronic and acute toxic effects, as they can be carcinogenic, mutagenic, teratogenic and immunosuppressive. AFB1 is considered as the strongest carcinogen of natural origin and it is normally predominant in crops and their derived products. Aflatoxin M1 is the main metabolite of aflatoxin B1 in humans and animals and as such it may be present in milk from animals fed with contaminated feed. Although the toxicity of M1 is about ten times lower than for B1, it also has hepatotoxic and carcinogenic effects. For the analysis of mycotoxins in cereals and/or milk, IAC in combination with HPLC are increasingly used as reference method due to their high selectivity and good elimination of matrix interferences. However, the cost of analysis using IAC is usually high. In recent years, molecularly imprinted polymers (MIP) have become very popular and promising materials for extracting different analytes in several matrices. AFs are too toxic to be used in MIP preparation, and template bleeding may be an additional problem, especially when dealing with very low levels. For this reason, in this study the use of a dummy template was preferred for MIP synthesis. A rapid, affordable and selective extraction method based on magnetic MIPs (MMIP) has been developed for the isolation of aflatoxins (B1, B2, G1, G2, M1), using a combination of imprinted polymers and magnetite. The successful MMIP stirring "cake" (used as a stir-bar) has been combined with HPLC-MS/MS for the determination of AFM1 in milk powder (infant formulas) to demonstrate its applicability to real samples.