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DRUGS been widely used in order to moderate efficacy and less side effects. With the \Commercialization of Chinese herbal medicine planting frequently use pesticides to prevent, repel or mitigate pests harm, this herbal medicine is also likely to pollution by pesticides. Therefore it is necessary to study the establishment of the new method of analysis of pesticide residues detected in Chinese herbal medicine. In recent years, Chinese herbal medicine in the detection of pesticide residues have been reported, but more focused on the detection of a single type of pesticide on many types of pesticides detected simultaneously reported relatively small. In this paper, the modern separation techniques to study the establishment of a new analysis method of Chinese herbal medicine in many types of organic pesticides, and achieved satisfactory results. The main findings are as follows: 1. Establish a new method for the simultaneous detection of 15 kinds of Chinese herbal medicine organophosphate and carbamate pesticide residues. By microwave-assisted extraction and ultrasonic extraction means to extract pesticide residues in Chinese herbal medicine, orthogonal design to optimize the extraction conditions and column chromatography to purify the extract, GC-NPD purification liquid detection. Under optimized conditions, the 21 pesticides in the 0.01 ~ 1.0 mg / L or 0.02 to 1.0 mg / L concentration range linear, linear correlation coefficient greater than 0.9950, the detection limit of 0.002 to 0.015 mg / L. Microwave assisted extraction and ultrasonic extraction, add the level of the average recoveries were 75.1% to 129% and from 70.6% to 129%, the relative standard deviation of 3.1% to 10.6% and from 1.0% to 17.8%, respectively. Both extraction methods to meet the requirements of pesticide testing, and applied to the analysis of real samples, the better. The first time microwave assisted extraction - dispersive solid phase extraction technology, combined with gas chromatography analysis of the means to establish a new method for the simultaneous detection of 16 kinds of Chinese herbal medicine organophosphorus pesticide residues. This method has a fast, reliable and environmentally friendly advantages. Anhydrous ethanol as extractant, microwave-assisted extraction of organophosphorus pesticide residues in Chinese herbal medicine, and dispersive solid phase extraction technology to purify the extract, greatly simplifies the process of operation, shorten analysis time and reducing the amount of solvent. 16 pesticides in 0.01 ~~ 1.0mg / L concentration range linear, linear correlation coefficient greater than 0.9992, the detection limit of 0.001 to 0.009 mg / L. Add as matrix recovery in four herbs addition to Isocarbophos, other pesticides recoveries between 73.8% to 123%, the relative standard deviation of less than 15.2%. These data show that the established pesticide residues determination to meet the requirements, and the method of the herbal matrix interference, successfully applied to the determination of pesticide residues of four herbs astragalus, chrysanthemum, ginkgo nuts and Mustard Seed. The first time using microwave assisted extraction - dispersive solid phase extraction technology, combined with gas chromatography - mass spectrometry analysis means 24 kinds of Chinese herbal medicine organophosphorus, organochlorine, carbamate and pyrethroid pesticide residues detected simultaneously new method. Samples by microwave assisted extraction and orthogonal design to optimize the extraction conditions. The extract was concentrated to near dryness, choice of n-hexane conversion solution by dispersive solid phase extraction technology to purify the extract, and studied the effect of aluminum oxide, graphite, carbon black, and PSA adsorbent purification, and ultimately chose 150 mg PSA and 100mg MgSO4. 0.01 ~ 0.5 mg / L concentration range of linear, linear correlation coefficient greater than 0.9971, the detection limit to 0.0002-0.01 mg / L, both qualitative and quantitative selected ion mode, 24 pesticides. Three add a level of recovery, most of the pesticide recoveries between 70% -110%, the relative standard deviation of less than 16.0%. The method of application of Astragalus samples of the 24 pesticides determination of pesticide residues, results were satisfactory.
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