Detection Of Pesticide Residues Screened In Bupleuri Radix Etl Seven Medicinal Materials

Pesticide residues of Chinese medicinal materials（TCM）had been seriously affected the clinical use in TCM.It was very important to build the simple and effective detection methods.With different medicinal sites and matrixes including Bupleuri Radix,Forsythiae Fructus,Ziziphi Spinosae Semen,Farfarae Flos,codonopsis radix,astragall radix,polygalae rdix as used as raw material,a rapid and accurate pesticide residue detection method was established and 107 samples were determined by GC-MS/MS.The study aimed to establish a rapid and accurate method for simultaneous determination of major groups of pesticides in representative medicinal parts of roots,fruits,seeds and flowers.The main results of investigation were as follows:（1）The study was to establish a method by optimizated-QuEchERS extraction and GC-MS/MS for simultaneous determination of 24 kinds of pesticides of organochlorines,organophosphorus and pyrethroids in seven TCM.Under the optimized condition,the limits of detections and quantifications（LOQ）for total pesticides ranged from 0.02 to 5.00μg·kg^-1 and LOQ 0.05 to 10.00μg·kg^-11 in seven TCM,respectively.The good linear relationships were obtained with R values of 0.9920-0.9999.Recovery ranges of pesticides in different spike levels were from 70.07%to 125.23%.The reliability of the method was also verified with an uncertainty study using a certified reference standard substance.And use the optimal method for the screening of pesticides in 62 samples.The collected samples were analyzed with the validated method.The results showed that 14 out of 24 pesticides were detected in 34 samples,involving 4 kinds of organochlorines（OCPs）,8 kinds of organophosphorus（OPPs）and 2 kinds of pyrethroids（PYRs）.The level of residues in different batches was in the range of 0.0027 to0.5400 mg·kg^-1.Persistent DDT and BHC were found in several samples at a low content,and ranged from 0.0029 to 0.0290 mg·kg^-1.At the same time,there were many pesticide residues.The occurrence of 1 to 2 kinds,3 to 4 kinds and 5 to 6 kinds of co-existent pesticides in the same sample was 25.80%,24.20%and 3.20%,respectively.（2）A method was established by simplified sating-out extraction and GC-MS/MS for the determination of 74 kinds of pesticides in Bupleuri Radix.And it was used in the optimal method for the screening of pesticides in 45 samples.Under the established condition,the LOD for total pesticides ranged from 2.50 to 25.00μg·kg^-1 and the LOQ ranged from 10.00 to 50.00μg·kg^-1,respectively.The R² values of the linear regression equation were from 0.9911 to0.9998.Recovery in three-level ranged from 72.31%to 122.00%.For actual samples analyzed,the results showed that only 8 pesticides were detected in 45 samples,including 1 kind of bactericide,2 kinds of OCPs,2 kinds of OPPs,3 kinds of PYRs.Persistent DDT were also found in several samples but at a low content,ranged from 0.0155 to 0.0222 mg·kg^-1 and were far below the limit standards(the sum of DDT≤0.2 mg·kg^-1).Among them,Chlorpyrifos was highly detected,with the residual amount up to 2.2229 mg·kg^-1(MRLs≤0.20 mg·kg^-1).There is also a small amount of excess standard in permethrin,in the samples with a residual amount of0.1930 mg·kg^-1(MRLs≤0.10 mg·kg^-1).