LC-MS/MS and LC-UV Determination of Moniliformin by Adding Lanthanide Ions to the Mobile Phase

Elution behavior of drugs in high-speed counter-current chromatography using on-column complexation with metal ions

In this study, determination of (nitrogen containing) drugs by on-column complexation with metal ions in high-speed counter-current chromatography (HSCCC) was investigated. Bromazepam (BMP) was strongly retained in the organic upper stationary phase (UP) of the two-phase solvent system composed of tert-butyl methyl ether-acetonitrile-water (2:2:3, v/v/v) by eluting the aqueous lower mobile phase (LP) at a flow rate of 2 mL min-1. On the other hand, BMP (200 µg mL-1) was eluted faster without retention to the organic UP with the two-phase system containing 100 μg mL-1 of copper ions (CuCl2) because a very polar BMP-Cu2+ complex was immediately formed in the aqueous LP. The dramatic change in the retention behavior of BMP resulted from on-column complexation. The on-column complexation in HSCCC was further investigated for five (nitrogen containing) drugs and seven metal ions. In the result, tizanidine and phentolamine formed complexes with Al3+, Fe2+, Co2+, Ni2+, Cu2+, and Zn2+, ambroxol formed complexes with Al3+, Fe2+, and Cu2+, but voriconazole formed no complexes with all metal ions tested.

Co-Occurrence of Moniliformin and Regulated Fusarium Toxins in Maize and Wheat Grown in Italy

The co-occurrence of moniliformin (MON), fumonisins (FBs), and deoxynivalenol (DON) was evaluated in maize, durum, and common wheat grown in different experimental fields located in several Italian regions. MON was quantified using a LC-MS/MS method adding lanthanum ions in the mobile phase. In maize, MON contamination was widespread and considerable; the toxin was detected in almost all the samples (95.1%) and exceeded 500 and 1000 µg kg-1 in 42.0% and in 18.5% of samples, respectively. Significant positive correlation was found between MON and FB contamination levels. When there were not droughty climate conditions, a positive significant correlation was found between growing degree days (GDD) and MON values. In wheat, MON contamination was not widespread like in maize and it was lower in common wheat than in durum wheat. In durum wheat, MON was detected in 45.0% of the samples with only 6 samples (7.5%) exceeding 500 µg kg-1, while in common wheat the toxin was detected above the LOD in 18.7% of samples exceeding 100 µg kg-1 in only two samples (2.5%). No correlation was found with DON contamination. Climate conditions influenced both MON and DON occurrence.

Application of LC-MS/MS in the Mycotoxins Studies

Mycotoxins are secondary metabolites produced by fungi of different species (mainly Aspergillus, Fusarium, and Penicillium) with toxic effects for humans and animals that can contaminate food and feed [...].