Simultaneous Determination of 16 Kinds of Pyrethroid and Carbamate Pesticide Residues in Dendrobium huoshanense and Dendrobium officinale from Huoshan by GC-MS

Gas chromatography-mass spectrometry(GC-MS)method for the simultaneous determination of 16 pyrethroid and carbamate pesticide residues in Dendrobium huoshanense and Dendrobium officinale from Huoshan was developed. The samples were extracted with acetonitrile. After being vacuum concentrated,the extract was purified by using SPE and QuEChERS pretreatments. GC-MS was tested by selective ion mode(SIM). The results showed that the working curves for 16 pesticides were linear in the range of 5.0~80.0 μg/mL. The SPE pretreatment recoveries of 16 pesticides at spiked level of 500 μg/L were 84.87%~95.96%,and relative standard deviations(RSD)were 4.08%~7.66%. The QuEChERS pretreatment recoveries of 16 pesticides at spiked level of 500 μg/L were 94.90%~104.91%,and relative standard deviations(RSD)were 2.23%~4.67%. The QuEChERS methods was slightly better than SPE about recoveries and relative standard deviations. The limits of quantitation were 0.0003~0.2331 μg/mL,the precision and stability were 1.02%~2.58% and 1.82%~2.97%,respectively. This method was rapid,sensitive and accurate and it could meet the demands for the determination of multi-pesticides in D. huoshanense and D. officinale samples from Huoshan.