Moniliformin Analysis in Maize Samples from North-West Italy Using Multifunctional Clean-up Columns and the LC-MS/MS Detection Method.

A fast clean-up method has been developed to purify maize extracts and to detect moniliformin (MON) in maize samples from North-West Italy over a four-year period (2008-2011). The method is based on the use of MycoSep® 240 Mon clean-up columns (Romer Labs®). Samples were extracted using acetonitrile/water (84:16, v/v), and the extracts were purified in the previously described clean-up columns. The LC-MS/MS analysis has been carried out by means of hydrophilic interaction chromatography (HILIC), combined with negative electrospray mass spectrometry (ESI- - MS). The developed method has a recovery rate of 76-91% (RSD%: 6-14%), a limit of detection (LOD) of 1 µg kg-1, and a limit of quantification (LOQ) of 4 µg kg-1. One hundred and eight different naturally contaminated maize samples were analyzed for their MON content. The average percentages of positive samples was 93% with the following ranges (µg kg-1): 33-2606 (2008); < LOD-527 (2009); < LOD-920 (2010); < LOD-409 (2011).