Research On Simultaneous Detection Of Multi-mycotoxins In Traditional Chinese Medicines And Their Related Products

The mycotoxins pollutions and residues in traditional Chinese medicines(TCMs) have brought serious security hidden danger to humans, and people all over the word have gradually attaches great importance to this problem. But, the complex matrices of TCMs usually led to some difficulties for the analysis, the relevant analysis methods are still can’t meet the comprehensive screening of mycotoxins in Chinese traditional medicines. Therefore, it is important to establish a simple, rapid and sensitive analytical method for the detection of multi-mycotoxins in TCMs and their related products to ensure their quality and safety. The main contents of this study were as follows:(1) Establishment of an UFLC-MS/MS method for simultaneous determination of 8 mycotoxins in Chinese yam and its related products.Through the optimization of some crucial parameters including extraction solvent, extraction method, chromatographic and mass spectrometric conditions, an UFLCMS/MS method was developed for high-throughput determination of aflatoxins(AFB1, AFB2, AFG1 and AFG2), ochratoxin A(OTA), fumonisins(FB1 and FB2) and zearalenone(ZEA) in Chinese yam and its related products. The results showed that the developed method showed satisfactory linearity(R2 = 0.9977~0.9999) with limits of detection(LODs) of 0.025-0.125 ng/mL, limits of quantification(LOQs) of 0.1-0.25 ng/m L, and recovery rates of 71.00-106.00%. Five samples were found to be positive with target mycotoxins(AFB1, FB1, FB2) and the contens of AFB1 in 2 samples exceeded the suggested maximum residue levels. OTA and ZEA were not detected in all the tested samples.(2) Development of an MFC-HPLC-PCD-FLD method for simultaneous determination of 4 aflatoxins in Radix paeoniae alba.Through the optimization of extraction solvents, the purification of MFC and chromatographic conditions, the HPLC-PCD-FLD method was developed for simultaneous determination of 4 aflatoxins(AFB1, AFB2, AFG1 and AFG2) in Radix paeoniae alba samples. The results showed that the established method showed satisfactory linearity(R2 = 0.9993~0.9999) with LODs of 0.03~0.18 μg/kg, LOQs of 0.09~0.5 μg/kg, and recovery rates of 80.49~100.41%. Three samples wee found to be positive and 1 sample was contaminated simultaneously with the 4 aflatoxins. The positive samples were confirmed by using UFLC-MS/MS method.(3) Development of an IMBs-UPLC-FLD method for rapid determination of AFB1 in Chinese yam.Through the optimization of the preparation process of IMBs, clean-up and chromatographic conditions, an IMBs-UPLC-FLD method was developed for rapid determination of AFB1 in Chinese yam. The best clean-up conditions of IMBs for tested samples were as follows: 20% methanol solution was selected as the enrichment system with enrichment time of 30 min; 1 mL of pure methanol was the elution solution for three times and 3 min for each time. The UPLC-FLD method was successfully validated to show satisfactory linearity(R2 = 0.9993) with LODs of 0.3 μg/kg, LOQs of 1 μg/kg, and recovery rates of ≥ 84%. The results showed that 2 samples were found to be positive with AFB1, and conten of AFB1 in 1 sample exceeded the suggested maximum residue levels, which was confirmed by the UFLC-MS/MS method. The established method was quick, easy and reliable and could be used for the detection of AFB1 in Chinese yam and other complex matrices.