Abstract:

The illegal addition of substances in ordinary food poses a serious threat to food safety. Therefore， the detection and identification of such additives have long been important research areas in the field of food safety. Especially， illegal additives are showing new trends now， such as emerging functional varieties， new structural derivatives， and clandestine addition practices. Meanwhile， along with the development of online shopping and logistics， new threats pose a substantial challenge to social governance and food safety. In recent years， there are frequent cases of people consuming wild mushrooms containing hallucinogenic tryptamine toxins out of curiosity， and the abuse of tryptamine psychoactive substances also occurs from time to time. Therefore， the development of a robust and sensitive analytical method is necessary for accurately identifying the risks associated with tryptamine psychoactive substances.To address this issue， a novel method based on ultra performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS） combined with an isotopic internal standard and solid-phase extraction purification technique was developed for the simultaneous determination of three tryptamines （psilocin， bufotenine and psilocybin） in ten types of ordinary foods. Several optimization procedures were undertaken， involving the chromatographic conditions， mass spectrometric parameters， and sample extraction and purification protocols. The food samples were extracted and centrifuged， followed by purification using a strong cation exchange solid-phase extraction column. The separation was carried out using a Capcell PAK ST （S-5） hydrophilic interaction chromatographic column. The multi-reaction monitoring （MRM） mode was employed for data acquisition in the positive ion mode， whereas isotopic internal standards were used to quantify the three tryptamines. It was verified that the calibration curves of psilocin， bufotenine， and psilocybin exhibited good linearities （R²>0.995） within the range of 0.025-10.0 ng/mL. The limits of detection （LODs） for psilocin， bufotenine and psilocybin were determined as 0.4， 0.5， and 0.6 µg/kg， respectively， while the limits of quantification （LOQs） were determined as 1.4， 1.7， and 1.9 µg/kg， respectively. The LODs and LOQs demonstrate that the method has the ability to detect minute quantities of tryptamines. The recoveries of the tryptamines were 94.3%-113.7% under three spiked levels， with relative standard deviations （RSDs） ranging from 0.4% to 4.9% （n=6）. The consistent and satisfactory recoveries of tryptamines indicate that this method meets the requirements to accurately quantify the target analytes even in a complex matrix. In summary， this newly developed method is rapid， sensitive， accurate， and compliant with relevant regulatory standards； hence， it is suitable for the determination of psilocin， bufotenine and psilocybin in food matrices. As part of the application of this method， a comprehensive investigation was conducted on ten types of actual food samples， including candies， beverages， wines， succade， coffee， health care products， condiments， cooked meat products， spices and hot pot sauce. As a result， out of 100 samples， 14 samples were found to contain bufotenine. Additionally， one sample had a bufotenine concentration of 7.6 mg/kg. By tracing back， it was discovered that the bufotenine in the positive samples was derived from Zanthoxylum armatum DC. or Zanthoxylum Bungeanum Maxim. Subsequently， 12 samples， containing Zanthoxylum armatum DC. and Zanthoxylum Bungeanum Maxim， were collected and processed using the same method， which revealed the bufotenine in all samples with the content ranging from 23.8 to 885.0 mg/kg. At the same time， it was found that the daughter ion scanning mass spectra of the Zanthoxylum Bungeanum Maxim sample were almost consistent with those of the bufotenine standard. Based on this， it can be firmly concluded that bufotenine is naturally present in Zanthoxylum armatum DC. and Zanthoxylum Bungeanum Maxim. In conclusion， the developed method and the discovery of the content of bufotenine in Zanthoxylum armatum DC. and Zanthoxylum Bungeanum Maxim provide a reference framework for future research in the areas of food safety risk assessment， the screening of illegal additives， and food product development.

Key words: ultra performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS）, foods, psilocin, bufotenine, psilocybin, solid phase extraction