论文部分内容阅读
目的建立中空纤维液相微萃取-高效液相色谱同时测定水中多种二苯醚类除草剂残留的分析方法。方法水样中8种二苯醚类除草剂(苯达松、氟磺胺草醚、三氟羧草醚、苯草醚、甲羧除草醚、乙羧氟草醚、除草醚、乙氧氟草醚)的残留经中空纤维膜萃取,采用C18色谱柱分离,以甲醇-三乙胺-盐酸溶液作流动相,梯度洗脱,在波长为300 nm处测定。采用聚偏氟乙烯中空纤维膜进行液相微萃取,分别优化了影响萃取效率的萃取剂种类、水样pH值、盐浓度、搅拌速度及萃取时间等条件,并对待测物检测波长、流动相梯度洗脱、流动相pH值、流速和柱温等色谱条件进行了优化。结果在优化的条件下,待测除草剂的质量浓度在0.001~0.20 mg/L(苯达松、氟磺胺草醚、三氟羧草醚、苯草醚)、0.001~0.10 mg/L(甲羧除草醚、乙羧氟草醚、除草醚、乙氧氟草醚)范围内与其峰面积呈良好的线性关系(r≥0.999),水样的平均加标回收率为78.0%~98.0%,相对标准偏差(RSD)为1.10%~6.90%(n=5);对于10.0 ml水样,本方法的检出限为0.20~0.40μg/L。结论本法简便、快速、准确、环境友好、灵敏度高,能满足环境水样中多种二苯醚类除草剂残留分析要求。
OBJECTIVE To establish a method for the simultaneous determination of various diphenylether herbicides residues in water by hollow fiber liquid phase microextraction coupled with high performance liquid chromatography. Methods Eight kinds of diphenyl ether herbicides (bentazon, fomesafen, acifluorfen, aconite, carbofuran, fenfid, fenpropadin, oxyfluorid Ether) was extracted by hollow fiber membrane and separated by C18 column. The mobile phase was methanol-triethylamine-hydrochloric acid solution and gradient elution was carried out at a wavelength of 300 nm. Polyvinylidene fluoride hollow fiber membrane was used for liquid phase microextraction. The conditions of extractant, water sample pH value, salt concentration, stirring speed and extraction time were optimized respectively. The detection wavelength, mobile phase Gradient elution, mobile phase pH, flow rate and column temperature were optimized. Results Under the optimized conditions, the mass concentration of the herbicide to be tested was between 0.001-0.20 mg / L (bentazon, fomesafen, acifluorfen, acifluorfen) and 0.001-0.10 mg / L Carboxyfenoxystrobin, fenpropadin, oxyfluorfen) and its peak area showed a good linear relationship (r ≥ 0.999), the average recovery of water samples was 78.0% to 98.0% The relative standard deviations (RSDs) ranged from 1.10% to 6.90% (n = 5). For the 10.0 ml water samples, the detection limit was 0.20-0.40 μg / L. Conclusion This method is simple, rapid, accurate, environmentally friendly and sensitive. It can meet the requirements of many kinds of residues of diphenyl ether herbicides in environmental water samples.