Straightforward Determination of Pyrrolizidine Alkaloids in Honey through Simplified Methanol Extraction (QuPPE) and LC-MS/MS Modes

Abstract

Contamination of honey with toxic pyrrolizidine alkaloids (PAs) and their N-oxides (PANOs) was assessed by dilution with acidic methanol and analysis through liquid chromatography (LC) coupled with tandem mass spectrometry (MS/MS) in three different modes. The hybrid linear trap/triple quadrupole (LC-QTRAP) instrument was used in precursor ion scan (PIS), enhanced product ion scan (EPI), and multiple reaction monitoring (MRM) mode. The parent ions from ions at m/z 120 or 138 amus, characteristic of all the toxic PAs and PANOs in the sample were first scanned by PIS. Then, the presence of each contaminant at specific retention times through its MS2 spectrum was confirmed by EPI. Finally, they were quantified in the MRM mode. The method was validated: recoveries 86–111%, relative standard deviation (RSD) <20%, at 20 and 40 μg/kg, except retrorsine, which showed a RSD of 30% at 20 μg/kg. Honey samples were analyzed and five of them showed levels of 40 μg/kg for the sum (PAs + PANOs). This approach allows the simultaneous determination of PAs and PANOs in honey, even if their chemical standards are not available.

An essay on ecosystem availability of Nicotiana glauca graham alkaloids: the honeybees case study

“…Such transfer though remains to be proven. Alkaloids in honey, such as pyrrolizidine based molecules (e.g., echimidine), are intensively studied in terms of residual prevalence [65,66] and some of the members display carcinogenic, hepatotoxic and other toxic pharmacological activities [67]. Despite their toxicity, the European Commission has not yet established their MRLs.…”

Application of the QuEChERS Strategy as a Useful Sample Preparation Tool for the Multiresidue Determination of Pyrrolizidine Alkaloids in Food and Feed Samples: A Critical Overview

“…Conversely, 22% of the works reviewed performed the salting-out extraction step of PAs as in the original QuEChERS procedure, using 4 g of MgSO 4 and 1 g of NaCl, also achieving good results (Table 1). Some authors have also evaluated the amount of NaCl added [22,23]. MgSO 4 can promote the distribution of analytes in the organic phase mainly by absorbing water, thus retaining some undesirable polar compounds from the sample matrix, such as sugars, improving the salting-out effect of the organic extraction solvent.…”

“…Accordingly, saturated aqueous solutions of NaCl would increase the solubility of the analytes in the organic phase. With this premise, Sixto et al (2019) evaluated increasing the amount of NaCl from 1 to 2 g to promote the salting out effect with the aim of improving the recovery values of the PANOs [22]. However, the recovery values were not affected by this modification.…”

Colorimetric Sensors for Alkaloids Based on the Etching of Au@MnO2 Nanoparticles and MnO2 Nanostars

“…Traditional methods for specific detection of alkaloids mainly rely on mass spectrometry, gas chromatography–mass spectrometry, and liquid chromatography–mass spectrometry. − These methods achieve high sensitivity and reproducibility. However, they require complex apparatus and time-consuming measurement processes. − Moreover, in medical diagnosis, the detection of alkaloids is often not limited to one but three or more. In this case, the above sensors based on the lock-key sensing mode are disabled.…”