活性白土在青菜有机磷农药检测中的研究

Effect of activated clay on the detection of organophosphorus pesticides in green vegetable

中文关键词:  活性白土  青菜  有机磷农药  检测

英文关键词:activated clay  green vegetable  organophosphorus pesticides  detection

中文摘要:

      目的 筛选对青菜基质成分净化效果最好的吸附剂, 并探究其对气相色谱检测青菜中有机磷农药的影响。方法 青菜经乙腈提取后, 用6种吸附材料分别进行基质成分净化, 利用紫外-可见光光谱图分析筛选对青菜基质成分净化效果最好的吸附剂, 并考察其加入量对净化效果的影响; 通过比较加标回收率, 考察该吸附材料对青菜中有机磷农药检测准确度的影响。结果 活性白土和石墨化碳黑能显著降低青菜提取液在436 nm和668 nm附近的吸光度。在气相色谱检测中, 随着活性白土加入量的增大, 敌敌畏、灭线磷、毒死蜱、杀螟硫磷、三唑磷的回收率逐渐减小, 甲胺磷、乙酰甲胺磷、久效磷、氧乐果、乐果的回收率先降低后升高。结论 活性白土对青菜的基质成分净化效果好, 但也对农药具有较强的吸附作用, 其在农药残留检测中的应用还有待进一步研究。

英文摘要:

      Objective To screen the best absorbents for purifying the matrix components of green vegetable, and investigate its effects on the gas chromatography detection of organophosphorus pesticides in green vegetable. Methods After extraction of samples of green vegetable by acetonitrile, adsorption materials were added to purify, the effect of adsorption materials on the matrix composition of the vegetable was analyzed by UV-Vis spectrum. The detection accuracy of organophosphorus pesticides was investigated by comparing the recovery. Results Activated clay and graphitized carbon black could effectively reduce the absorbance of the vegetable around 436 nm and 668 nm. With the increasing addition of activated clay, the recoveries detected by the gas chromatography of methamidophos, dichlorvos, chlorpyrifos, fenitrothion, and triazophos were gradually decreased, but the recoveries of methamidophos, acephate, omethoate, monocrotophos, and dimethoate were firstly decreased and then increased. Conclusion Activated clay has good purification effect on the matrix components of green vegetable, but it also has strong adsorption on pesticides. Its application in pesticide residue detection needs further study.