Simultaneous determination of 114 pesticides in complex Chinese herbal medicine using ordered mesoporous carbon CMK-3 as a reversed-dispersive solid phase extraction sorbent.

, a traditional Chinese herbal medicine, is classified into many medicinal species and contains numerous complex components. It is thus difficult to simultaneously detect multiple pesticide residues in different species. An easy, reliable, and widely applicable analytical method based on a modified Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method coupled with LC-MS/MS was developed to solve these problems encountered during pesticide residue analysis in complex matrices. Ordered mesoporous carbon CMK-3 and a primary secondary amine (PSA) were used as efficient purification sorbents by optimization of the QuEChERS process. Systematic method validation was performed for four species of . The matrix effect of pesticides varied among different species, and matrix-matched standard solutions were thus employed for quantitative analysis. The mean recoveries of all pesticides ranged from 88.6% to 95.5%, with mean relative standard deviations (RSD) lower than 6% at spiked concentrations of 30, 120, and 240 μg kg. The limits of quantification (LOQ) for the developed method were in the range of 30-120 μg kg. This method was further used to analyze 47 samples from Zhejiang province, China, and seven pesticides were detected in 22 samples. These results demonstrate that the developed method is suitable for an accurate analysis of multiple pesticide residues in various .