ZEARALENONE AND ALTERNARIOL MYCOTOXINS IN OIL SAMPLES

MOLECULARLY IMPRINTED POLYMERS FOR THE SIMULTANEOUS ANALYSIS OF ZEARALENONE AND ALTERNARIOL MYCOTOXINS IN OIL SAMPLES

T. Moya-Cavas,1 J. Urraca,1 Luis A. Serrano-González,2 M.C. Moreno-Bondi1 1 Departments of Analytical and 2 Organic Chemistry, Faculty of Chemistry, Complutense University of Madrid, 28040 Madrid, Spain

tammoya@ucm.es

Molecularly imprinted polymers are tailor made materials containing specific recognition cavities with a predetermined selectivity for a specific analyte or group of similar analytes. In this work, we report the development of MIPs for the simultaneous preconcentration of zearalenone (ZON) and alternariol (AOH) in oil samples using molecularly imprinted solid phase extraction (MISPE). The polymers were prepared with N-(2-aminoethyl) methacrylamide as functional monomer, methacrylamide as co-monomer and ethylene glycol dimethacrylate as cross-linker. Two template molecules, namely, 3,8,9-trihydroxy-6H-dibenzo[b,d]pyran-6-one and cyclododecyl 2,4dihydroxybenzoate, were used as subrogates of AOH and ZON, respectively, for MIP synthesis. The MISPE method was optimized using a chemometric approach that maximized the selective retention of both mycotoxins in the MIP vs the NIP. . In the optimized conditions the cartridges, filled with 150 mg of a mixture (50:50, w/w) of the AOH/ZON selective MIPs, were loaded with 30 mL of sample, followed by a washing step with 2 mL of ACN/water (20/80, v/v) and elution with 2.5 mL of trifluoroacetic acid/MeOH (3/97, v/v). The extracts were analyzed by HPLC coupled to a fluorescence detector (FLD). No cross-reactivity was observed in the presence of mycotoxins from other families. The optimized MISPE-HPLC-FLD method, has been applied to the analysis of the mycotoxins in maize oil samples (2 g) with a limit of detection of 2 and 5 μg kg-1 for AOH and ZON, respectively. Recoveries in the range of 94% to 113% (RSD < 5%, n = 6) for AOH and 92% to 108% (RSD < 6%, n = 6) for ZON were obtained in the analysis of spiked maize oil samples. The method has been validated based on the European Commission Decision 2002/657/EC. The results have been confirmed by HPLC-MS/MS.

Acknowledgements. Work funded by the Spanish MCIN (grant RTI2018-096410-B-C21). TMC thanks the MCIN por a predoctoral grant.

Keywords: molecularly imprinted polymers, mycotoxin, alternariol, zearalenone, food analysis

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