Main content area

A fast and simple LC-ESI-MS/MS method for detecting pyrrolizidine alkaloids in honey with full validation and measurement uncertainty

Valese, Andressa Camargo, Molognoni, Luciano, de Sá Ploêncio, Leandro Antunes, de Lima, Flávia Gontijo, Gonzaga, Luciano Valdemiro, Górniak, Silvana Lima, Daguer, Heitor, Barreto, Fabiano, Oliveira Costa, Ana Carolina
Food control 2016 v.67 pp. 183-191
detection limit, honey, ionization, liquid chromatography, monitoring, monocrotaline, natural toxicants, retrorsine, statistical analysis, tandem mass spectrometry, uncertainty, Brazil
A fast and simple method was developed to determine pyrrolizidine alkaloids (PAs) in honey using liquid chromatography tandem mass spectrometry (LC- MS/MS) with electrospray ionization (ESI). An efficient extraction procedure was carried out by simply diluting with water, without the need of any additional clean-up steps. A full validation of the method was performed according to Commission Decision 2002/657/EC. The method was linear in the 050 μg kg−1 range and presented satisfactory intra-day and inter-day precision with relative standard deviations of 1.45–10.2% and 1.60–1–0.2%, respectively. The measurement uncertainty, limit of detection (LOD) (0.1–1.0 μg kg−1) and limit of quantification (LOQ) (0.2–1.5 μg kg−1) were also calculated. The proposed method was applied to analyse eight PAs, namely, senecionine, senecionine-N-oxide, echimidine, intermedine, lycopsamine, retrorsine, monocrotaline and retrorsine-N-oxide, in 92 commercial honey samples from Brazil. At least three PAs were detected in 99.1% of the samples. PAs were not detectable (<LOD) in only one sample. Because PAs are natural toxins biosynthesized by plants, the importance of monitoring their concentration in honey is evident. For this purpose, a simple, low-cost extraction procedure was performed, and a high-throughput method was developed.