Sara Elsa Aita, Andrea Cerrato, Aldo Laganà, Carmela Maria Montone, Enrico Taglioni, Anna Laura Capriotti

Dipartimento di Chimica, Università degli Studi di Roma “La Sapienza”, 00185 Roma, Italy

Patulin (PAT) is an α,β-unsaturated γ-lactone mycotoxin produced as a secondary metabolite by over 60 different species of fungi, with Penicillium expansum posing the greatest risk to human health and market stability [1]. Penicillium expansum species is commonly linked to post-harvest diseases in apples, though other fruits such as pears, citrus, and grapes can also be affected [2,3,4]. In this study [5], a PAT-specific molecularly imprinted polymer was successfully synthesized using dopamine and melamine as functional monomers, with formaldehyde as the cross-linker. The resulting material contained numerous hydrophilic groups, including hydroxyls, imino groups, and ether linkages. Notably, uric acid was used as a dummy template due to its structural similarity to PAT. Comprehensive characterization of the adsorption process was performed through adsorption isotherms and kinetic studies. Separation, identification, and quantification of PAT were achieved via ultra-high performance liquid chromatography coupled with photodiode array detection and tandem mass spectrometry, crucial for confirming PAT presence in real samples. The methodology was validated using 20 apple juice samples, demonstrating the polymer's high selectivity and specific adsorption capacity, with average recoveries of 85–90% and a relative standard deviation below 15%. The molecularly imprinted polymer exhibited excellent linearity in the concentration range of 1–100 ng/mL, with an R² value greater than 0.99. Additionally, the method provided a low limit of detection (0.5 ng/mL) and limit of quantification (1 ng/g). The hydrophilic nature of the developed polymer enabled efficient purification of apple juice samples due to strong polar interactions with the target analyte.

Keywords: Dopamine-formaldehyde-melamine MIP, UHPLC-MS/MS, Mycotoxins, Fruit juice analysis

References

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