Abstract:

A high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was established
to detect chloramphenicol residue in propolis-derived health foods. Samples were dissolved in 0.5% Ca(OH)2 solution,
followed by the removal of mucinous impurities after treatment with hydrochloric acid. Then chloramphenicol was back
extracted with ethyl acetate. The extract was separated on an Inertsil C8-3 column (2.1 mm × 100 mm, 2 μm) with gradient
elution using a mobile phase consisting of methanol and water. A tandem quadrupole mass spectrometer equipped with
electrospray ionization (ESI) source in positive ion mode was employed for the quantitative analysis of the analyte using
multiple reaction monitoring (MRM). The calibration curve for chloramphenicol displayed good linearity in the range of
0.1–2.0 ng/mL. The limit of detection (LOD) of the proposed method was 0.4 ng/mL. The absolute recoveries were 58.3%–
74.5% at spiked concentration levels of 0.1, 0.2, and 1.0 μg/kg with relative standard deviations (RSDs) of 1.34%–5.11%,
and the relative recoveries were 96.8%–114.0% with RSDs of 1.33%–5.36%. The method exhibited high sensitivity and
good reproducibility, and could be suitable for the determination of trace amounts of chloramphenicol in propolis-derived
health foods.

Key words: HPLC-MS/MS, propolis, health foods, chloramphenicol