Rapid and high-throughput measurement of cyanide in liquor by negative photoionization time-of-flight mass spectrometry

Cyanide is inevitably present in fermented liquors made from cyanogenic plants, which should be strictly controlled for safe drinking. Rapid access to cyanide content during liquor production is crucial for product safety and quality control. In this study, a rapid and high-throughput method for the measurement of cyanide in liquor was developed by coupling negative photoionization time-of-flight mass spectrometry (NPI-TOF) and a simple alkalization-dilution-acidification pretreatment procedure. The method detection limit (MDL) and practical quantitation limit (PQL) of 0.05 and 2.50 μg L−1 for cyanide in liquor were obtained within 1 min. The cyanide concentrations in 200 samples of Chinese liquor from the 2nd to 7th distillation rounds were rapidly determined by the developed method, and the samples from the 4th and 5th distillation rounds had the lowest cyanide content with average concentrations of 309 and 306 μg L−1, respectively, which were consistent with the final quality assessment results. [Display omitted] •Rapid derivatization of cyanide in liquor into gas phase HCN.•Unique ion CN- for cyanide analysis without spectral interference within 1 min•Method detection limit and practical quantitation limit of 0.05 and 2.50 μg/L.•Good agreement of the results between NPI-TOF and ion chromatography methods.