Indirect determination of aflatoxin B1 in beer by a multicommuted optical sensor

Lucía Molina Molina García (1) , M. Luisa Fernández de Córdova (1) , Antonio Ruiz Medina (2)

1 Physical and Analytical Chemistry
2 Physical and Analytical Chemistry

This manuscript reports the determination of Aflatoxin B1 (AFB1), mycotoxin which is considered one of the most carcinogenic substances known. A multicommuted flow injection-solid phase spectroscopy (FI-SPS) system combined with photochemically-induced fluorescence (PIF) is developed, for the first time, for its determination with quantitative purposes. A strongly fluorescent degradation product is obtained on-line by irradiation with ultraviolet light. The determination is carried out by measuring the fluorescence intensity of the photoproduct at 353/424 (λex/λem), once retained on C18 silica gel filling the flow-cell. A linear dynamic range of 0.09-12 μg L-1, detection limit as sensitive as 29 ng L-1 and a relative standard deviation (RSD) of 1.4% were obtained. The method proposed has been satisfactorily applied to the determination of AFB1 in different types of beer (normal and non-alcoholic). Hydrophobic compounds are eliminated from beer samples and AFB1 is extracted with acetonitrile by solid-phase extraction on C18 sorbent. Recoveries of the target compound from spiked beers are between 94-106%. The results obtained in the analysis of real samples are in good agreement with those provided by a reference chromatographic method.

Mots clés: Life Sciences

Lucía Molina Molina García, M. Luisa Fernández de Córdova, Antonio Ruiz Medina. Indirect determination of aflatoxin B1 in beer by a multicommuted optical sensor. Food Additives and Contaminants, 2012, pp.1. ⟨10.1080/19440049.2011.643244⟩. ⟨hal-00780025⟩