A simple, rapid, and precise method for the determination of cyclopiazonic acid (CPA) in liquid seasoning was developed, which uses liquid chromatography with ultraviolet and photodiode array detection LC/UV(PDA) and liquid chromatography with time-of-flight mass spectrometry (LC/TOF-MS). CPA in liquid seasoning was subjected to ethyl acetate extraction, and solid-phase extraction using Oasis® HLB. LC/UV(PDA) was used for qualitative and quantitative analysis, and LC/TOF-MS was used as the confirmatory method. The limit of detection (S/N = 3) and the limit of quantification (S/N > 10) of CPA in LC/UV(PDA) were 0.01 μg/mL and 0.03 μg/mL, respectively. Standard materials were prepared for quality control samples (a low concentration of 0.2 μg/mL and a high concentration of 2.0 μg/mL), and internal quality control was performed. As a result, the trueness of the low concentration sample and the high concentration samples was 80.3% and 81.6%, respectively. The relative standard deviation (RSD) of repeatability was 5.3% or less, whereas that of intermediate precision was less than 10.1%. The results suggest that the developed method is useful for the determination of CPA in liquid seasoning.
