Strategy for a Fast and Simple Method for Trace Determination of Senecionine and Senecionine N-Oxide in Honey Using LVI in HPLC-MS/MS

Abstract

The aims of this study were to develop an HPLC-MS/MS method for the trace determination of senecionine (SEN) and senecionine N-oxide (SENNOX) in honey samples with simple dilution and to optimize the strategy for large volume injection (LVI). In the method development, the quantity of sugar, injection volume and sample pH were optimized to increase the efficiency and the retention factor of the analytes. Figures of merit of the proposed method include: good linearity (R2 > 0.99), limits of detection of 57 and 59 ng·kg﹣1 for SEN and SENNOX, respectively, and recovery in the range of 83.4% - 123%. The values for the instrumental precision in relation to the retention time and peak area were 0.65% and 7.1%, respectively, and for the intra-day precision they were greater than 0.95% and 9.7% for SEN and SENNOX, respectively. The LVI-HPLC-MS/MS procedure developed was applied to honey samples prepared by simple dilution with deionized water (1:8 w/w) and the pH was adjusted to 9.5 with NH4OH. The sample volume injected was 100 μL; concentrations in natural and industrialized honey were ﹤LOQ - 1071.3 μg·kg﹣1 for SEN and ﹤LOD - 16.9 μg·kg﹣1 for SENNOX.