聚甲基丙烯酸酯类整体柱的构筑及固相萃取水果中杀虫剂残留的研究
发布时间：2018-08-31 07:40
【摘要】：目的由于水果样品组成复杂,需要在色谱分析之前,对样品进行固相萃取前处理以去除杂质,浓缩痕量目标物。为了克服传统的填充型萃取柱难以重复使用、操作繁琐的缺点,构筑了一种可重复使用的以甲基丙烯酸异辛酯为单体的疏水作用整体柱,结合高效液相色谱,建立了水果中除虫脲和氟铃脲的分析测定方法。方法1以甲基丙烯酸异辛酯(EHMA)为单体,乙二醇二甲基丙烯酸酯(EDMA)为交联剂,在不锈钢柱管(10 mm×4.6 mm,i.d.)中通过原位聚合反应合成poly(EHMA-co-EDMA)整体柱。实验考察了致孔剂的种类、致孔剂的比例、单体和交联剂的比例对整体柱性能的影响,并对整体柱的机械强度、表面形貌和比表面积等参数进行表征。2将合成的poly(EHMA-co-EDMA)整体柱作为固相萃取吸附剂用于水果中除虫脲和氟铃脲残留的前处理。实验优化了固相萃取主要的影响参数,包括上样流动相种类(纯水、5 mmol/L和10 mmol/L乙酸铵缓冲溶液、0.1%和0.5%甲酸溶液)、上样流速(0.1 m L/min、0.3 m L/min和0.5m L/min)、洗脱流动相种类(甲醇、乙腈、0.5%和1.0%甲酸乙腈)、洗脱流速(0.3 m L/min、0.5 m L/min、1.0 m L/min)。3在最佳实验条件下,对方法的线性范围、检出限、定量限、回收率和精密度等分析特征量进行验证。此外,在相同条件下通过同一根poly(EHMA-co-EDMA)整体柱不同使用次数固相萃取除虫脲和氟铃脲得到的色谱峰峰面积,计算相对标准偏差,评价该吸附剂的重复性。结果1实验选择致孔剂十二醇和N,N-二甲基甲酰胺(DMF)的比例为5:1(V/V),单体和交联剂比例为1:5(摩尔比),在60℃下反应16 h制得poly(EHMA-co-EDMA)整体柱,该整体柱柱床均匀、连续多孔,比表面积为164.01m2/g。2将poly(EHMA-co-EDMA)整体柱作为固相萃取吸附剂结合高效液相色谱对水果中除虫脲和氟铃脲进行分析测定。实验在0.1 m L/min流速下以5 mmol/L乙酸铵缓冲溶液为上样流动相,在流速为1.0 m L/min条件下以乙腈为洗脱流动相将目标物洗脱后,进C18柱分析。3该方法在0.1?50.0?g/m L范围内线性关系良好,相关系数(r)≥0.998,对除虫脲和氟铃脲的检出限和定量限分别为:0.0072,0.009 mg/kg和0.024,0.03 mg/kg,在浓度为0.03 mg/kg、0.3 mg/kg和1.5mg/kg,3个水平的加标回收率为89.5%~102.1%,日内和日间相对标准偏差≤6.83%。Poly(EHMA-co-EDMA)整体柱第1次、第25次和第75次使用,除虫脲和氟铃脲色谱峰峰面积的相对标准偏差均小于5.2%。结论基于poly(EHMA-co-EDMA)整体柱作为固相萃取吸附剂结合高效液相色谱,建立水果中除虫脲和氟铃脲残留的分析测定方法,满足水果中除虫脲和氟铃脲的常规分析测定要求。Poly(EHMA-co-EDMA)整体柱不仅对水果中的农药具有良好的净化作用,而且与传统的一次性使用固相萃取吸附剂相比制备简单、重复性良好,可重复使用75次以上。
[Abstract]:Objective due to the complex composition of fruit samples, it is necessary to pretreat the samples with solid phase extraction before chromatographic analysis to remove impurities and concentrate trace targets. In order to overcome the disadvantages of the traditional packed extraction column which is difficult to reuse and difficult to operate, a hydrophobic monolithic column with isooctyl methacrylate as monomer was constructed, which was combined with high performance liquid chromatography (HPLC). A method was established for the determination of diflufluuron and fluoridias in fruit. Methods 1 using isooctyl methacrylate (EHMA) as monomer and ethylene glycol dimethacrylate (EDMA) as crosslinking agent, a stainless steel column tube (10 mm 脳 4.6 mm,i.d.) was prepared. Poly (EHMA-co-EDMA) monolithic column was synthesized by in situ polymerization. The effects of the types of pore-forming agents, the proportion of pore-forming agents and the ratio of monomer to crosslinking agent on the properties of the monolithic column were investigated, and the mechanical strength of the monolithic column was also investigated. The surface morphology and specific surface area were characterized. 2 the synthesized poly (EHMA-co-EDMA) monolithic column was used as a solid phase extraction adsorbent for the pretreatment of fluoridias and fluoridias in fruit. The main parameters of solid-phase extraction were optimized, including the types of mobile phase (5 mmol/L pure water and 10 mmol/L ammonium acetate buffer solution 0.1% and 0.5% formic acid solution), the flow rate of 0.1 mL / min 0.3m L/min and 0.5m L/min, and the type of elution mobile phase (methanol). Under the optimum experimental conditions, the linear range, detection limit, quantitative limit, recovery rate and precision of the method were verified. In addition, under the same conditions, the peak area of the chromatographic peak was obtained by solid-phase extraction with the same poly (EHMA-co-EDMA) monolithic column for different times. The relative standard deviation was calculated and the repeatability of the adsorbent was evaluated. Results 1 the poly (EHMA-co-EDMA) monolithic column was prepared by reaction at 60 鈩，
本文编号：2214331
[Abstract]:Objective due to the complex composition of fruit samples, it is necessary to pretreat the samples with solid phase extraction before chromatographic analysis to remove impurities and concentrate trace targets. In order to overcome the disadvantages of the traditional packed extraction column which is difficult to reuse and difficult to operate, a hydrophobic monolithic column with isooctyl methacrylate as monomer was constructed, which was combined with high performance liquid chromatography (HPLC). A method was established for the determination of diflufluuron and fluoridias in fruit. Methods 1 using isooctyl methacrylate (EHMA) as monomer and ethylene glycol dimethacrylate (EDMA) as crosslinking agent, a stainless steel column tube (10 mm 脳 4.6 mm,i.d.) was prepared. Poly (EHMA-co-EDMA) monolithic column was synthesized by in situ polymerization. The effects of the types of pore-forming agents, the proportion of pore-forming agents and the ratio of monomer to crosslinking agent on the properties of the monolithic column were investigated, and the mechanical strength of the monolithic column was also investigated. The surface morphology and specific surface area were characterized. 2 the synthesized poly (EHMA-co-EDMA) monolithic column was used as a solid phase extraction adsorbent for the pretreatment of fluoridias and fluoridias in fruit. The main parameters of solid-phase extraction were optimized, including the types of mobile phase (5 mmol/L pure water and 10 mmol/L ammonium acetate buffer solution 0.1% and 0.5% formic acid solution), the flow rate of 0.1 mL / min 0.3m L/min and 0.5m L/min, and the type of elution mobile phase (methanol). Under the optimum experimental conditions, the linear range, detection limit, quantitative limit, recovery rate and precision of the method were verified. In addition, under the same conditions, the peak area of the chromatographic peak was obtained by solid-phase extraction with the same poly (EHMA-co-EDMA) monolithic column for different times. The relative standard deviation was calculated and the repeatability of the adsorbent was evaluated. Results 1 the poly (EHMA-co-EDMA) monolithic column was prepared by reaction at 60 鈩，
本文编号：2214331
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