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101.
Summary A computer-assisted method is described for optimization of multi-component, mobile phase selection for separating enantiomers of four pesticides in normal-phase HPLC. The method is based on the triangle, solvent-selection concept using a statistical scanning method. The optimization of the separation over the experimental region is based on a special polynomial estimation from seven experimental runs, and resolution (Rs) is used as the selection criterion. Excellent agreement was obtained between predicted and experimental data. 相似文献
102.
电化学生物传感器在农药检测中的应用 总被引:7,自引:0,他引:7
农药包括杀虫剂、杀菌剂、除草剂等,在种植业、养殖业、园林业等领域中有着广泛的应用。全球快速增长的农药使用量给环境、人的身体健康带来了潜在的危害。农药的种类繁多(多达几千种),结构各异,并且在样品中的含量极低(但毒性可能高)。针对这一问题,欧盟提出60多种使用量较大, 相似文献
103.
104.
Development of a class selective immunoassay for the type II pyrethroid insecticides 总被引:1,自引:0,他引:1
A general and broad class selective enzyme-linked immunosorbent assay was developed for the type II pyrethroid insecticides, such as cypermethrin, deltamethrin, cyhalothrin, cyfluthrin, fenvalerate, esfenvalerate and fluvalinate. Polyclonal antibodies were generated by immunizing with a type II pyrethroid immunogen ((RS)-α-cyano-3-phenoxybenzyl (RS)-cis,trans-2,2-dimethyl-3-carboxyl-cyclopropanecarboxylate) conjugated with thyroglobulin. Antisera were screened against nine different coating antigens. The antibody-antigen combination with the most selectivity for type II pyrethroids such as cypermethrin was further optimized and tested for tolerance to co-solvent, pH and ionic strength changes. The IC50s of the optimized immunoassay were 78 μg l−1 for cypermethrin, 205 μg l−1 for cyfluthrin, 120 μg l−1 for cyhalothrin, 13 μg l−1 for deltamethrin, 6 μg l−1 for esfenvalerate, 8 μg l−1 for fenvalerate and 123 μg l−1 for fluvalinate. No cross-reactivity was measured for the type I pyrethroids such as permethrin, bifenthrin, phenothrin, resmethrin and bioresmethrin. This assay can be used in monitoring studies to distinguish between type I and II pyrethroids. 相似文献
105.
《Journal of separation science》2003,26(14):1269-1272
Carbendazim residues were analyzed by column‐switching high‐performance liquid chromatography (HPLC) with photodiode array detection (PDA). The active ingredient was extracted by matrix solid‐phase dispersion (MSPD) from wheat grain on an acidic silica gel column using a methanol‐dichloromethane mixture. The recovery rate for fortified samples was 87.3 ± 3.3% with a standard deviation (SD) of 2.9%. The detection limit was 0.02 μg/mL. The method was applied to the determination of carbendazim residues in wheat grain samples from a treated field. 相似文献
106.
红外光谱分析是基于分子振动与跃迁理论的鉴别物质化学组成的技术.得到的光谱数据常常具有较高的维数和重叠度,这给后续的数据处理带来困难.为此提出一种GK可能C均值聚类算法(GKIPCM),引入了GK聚类算法的马氏距离测度与改进的可能C均值聚类算法(IPCM)的模糊隶属度与聚类中心更新方程,使样本的距离测度具有自适应性且避免... 相似文献
107.
提出了苹果、土豆、西红柿中除草通残留量的电分析化学测定方法,研究了除草通在汞电极上的电化学行为,探讨了其电极反应机理。结果表明,除草通在汞电极上具有吸附性质,其电极反应为不可逆的还原过程。本方法的测量线性范围为0.01~0.16mg/L,检出限为9.1μg/L. 相似文献
108.
109.
A critical study of a solid phase extraction method using C18 SPE columns for the determination of 23 halogenated pesticides is presented. Type of sorbent, sorbent mass, flow rate in the extraction process, sample concentration of the different compounds, sample volume, pH, ionic strength and type of water were evaluated. Recoveries of pesticides under study yield a linear relationship, except for conazole fungicides and captan. Losses can be expected for heptachlor, aldrin, and captan. Sample volume and flow rate of extraction affect recoveries. Matrix effects from surface and groundwaters were observed. Recoveries for vinelozolin and dieldrin from groundwater were lower than those obtained from nanopure water. In river water losses of these compounds are higher. Captan and penconazole were not present and high losses were obtained for trifluralin, α-BHC, γ-BHC, tri-allate and chlorpyriphos. Impurities arising from the sorbent materials of cartridges have been detected. 相似文献
110.