Simultaneous determination of bifenox, dichlobenil and diclofop methyl by hollow carbon nanospheres enhanced magnetic carboxylic multi-walled carbon nanotubes.
Simultaneous determination of bifenox, dichlobenil and diclofop methyl by hollow carbon nanospheres enhanced magnetic carboxylic multi-walled carbon nanotubes.
复制标题
DOI：
10.1016/j.aca.2018.01.030
复制
发表时间：
2018-06
影响因子：
6.2
通讯作者：
Wen-kui Li;Hai-xia Zhang;Yan-Ping Shi
中科院分区：
文献类型：
--
作者：
Wen-kui Li;Hai-xia Zhang;Yan-Ping Shi
建立了磁固相萃取(MSPE) -高效液相色谱-二极管阵列检测（HPLC-DAD）同时测定三种除草剂的新方法。该方法的关键是所探索的萃取剂，即中空碳纳米球（hcs）增强磁性羧基MWCNTs复合材料（HCSs@Fe3O4-MWCNTs-COOH）。MWCNTs-COOH通过毛细管力的振荡和超声作用插入hcs的孔隙中，使复合材料的羧基和结构间隔比MWCNTs-COOH增加，从而增强了萃取剂的亲水性、分散性、吸附性和选择性。萃取剂对多芳环结构、氢键受体较多、分子极性表面积较大的分析物敏感，这可能是由于氢键和π-π电子给体-受体（EDA）相互作用所致。对萃取剂的形貌、结构和磁性能进行了表征。将所建立的萃取剂MSPE-HPLC-DAD法应用于小麦粉样品中联苯（BFO）、二氯苯（DCB）和甲基双氯敌敌畏（DCM）的测定。在实际样品分析之前，对溶液pH、提取时间、加盐量和温度等关键提取参数进行了研究和优化，并对分析方法进行了评价。结果表明，该方法线性系数均在0.99以上，精密度良好，RSD < 3.5%，回收率为88.8% ~ 96.6%，低检出限（LOD）分别为0.39、0.24和0.68 ng/g。建立的MSPE-HPLC-DAD方法在复杂基质样品中选择性测定微量极性除草剂具有较大的潜力。
A novel analytical method based on magnetic solid-phase extraction (MSPE) coupled with high performance liquid chromatography-diode array detection (HPLC-DAD) was established for three herbicides simultaneous determination. The key of the method was the explored extractant, which was a composite of hollow carbon nanospheres (HCSs) enhanced magnetic carboxylic MWCNTs (HCSs@Fe3O4-MWCNTs-COOH). MWCNTs-COOH was inserted in the pores of HCSs by oscillation and sonication with the capillary forces, making the carboxylic groups and structure intervals of the composite increase as compared to MWCNTs-COOH, therefore the extractant exhibited enhanced hydrophilicity, dispersibility, adsorptivity and selectivity. The extractant was sensitive to analytes with the structure of multi-aromatic ring, more hydrogen bond acceptor and large molecular polar surface area, which can be attributed to hydrogen bonding and π-π electron-donor-acceptor (EDA) interactions. The morphology, structure and magnetic property of the extractant were characterized. Then the explored extractant based MSPE-HPLC-DAD method was applied for bifenox (BFO), dichlobenil (DCB) and diclofop methyl (DCM) determination from wheat flour samples. Prior to real sample analysis, critical extraction parameters such as solution pH, extraction time, salt addition and temperature were investigated and optimized, and the analytical method was evaluated. It was indicated that the method had satisfactory linearities with the linear coefficients above 0.99, good precision with the RSD less than 3.5%, desirable recoveries ranged from 88.8% to 96.6%, and low limits of detection (LOD) that were 0.39, 0.24, and 0.68 ng/g for DCB, BFO and DCM, respectively. The established MSPE-HPLC-DAD method has great potentials for trace polar herbicides selective determination from complex matrix samples.