Cellulose-ferrite nanocomposite for monitoring enniatins and beauvericins in paprika by liquid chromatography and high-resolution mass spectrometry

Talanta. 2021 May 1:226:122144. doi: 10.1016/j.talanta.2021.122144. Epub 2021 Jan 28.

Abstract

Paprika is considered a high-quality product being one of the most consumed spices in the world. Contamination with mycotoxins may appear due to inappropriate practices during processing or resulting from invading mould in the final manufactured products. A sample treatment based on dispersive magnetic solid-phase extraction (DMSPE) has been proposed for emerging mycotoxin determination, enniatins (ENNs) and beauvericins (BEAs), in paprika. Different magnetic nanoparticles were tested, and cellulose-ferrite nanocomposite was selected for the extraction and preconcentration of the mycotoxins. Nanocomposite was characterised using field emission scanning electron microscopy and energy dispersive X-ray spectroscopy in terms of morphology and elemental composition. High-resolution mass spectrometry allowed the quantification of the five main emerging mycotoxins and the monitoring of unexpected members of this class of toxic fungal secondary metabolites. The method has been validated, obtaining limits of quantification between 9.5 and 9.9 μg kg-1 and testing its trueness through recovery studies, with satisfactory values of between 89.5 and 97.7%. Relative standard deviations were calculated to evaluate the intra- and inter-day precision and values lower than 8% were obtained in all cases. The analysis of 26 samples, including conventional and organic, demonstrated the presence of ENNB1 at 12.0 ± 0.6 μg kg-1 in one of the samples studied. Other analogues ENNs and BEAs were not detected.

Keywords: Beauvericins; Cellulose-ferrite nanocomposite; Emerging mycotoxins; Enniatins; High-resolution mass spectrometry; Paprika.