纳米多孔双金属氧化物在镍钛合金纤维上的原位生长及其对多环芳烃的选择性固相微萃取

In situ growth of bimetallic oxide nanopores on nickel-titanium alloy fibers for selective solid-phase microextraction of polycyclic aromatic hydrocarbons

采用阳极氧化法在镍钛合金(NiTi)纤维上原位生长了双金属氧化物纳米孔(NiTiONPs)涂层,通过扫描电镜(SEM)和能谱(EDS)考察了电解质组成和电压对形貌的影响。将NiTiONPs涂层的NiTi纤维与高效液相色谱-紫外检测器联用,研究了4种典型芳香分析物的萃取性能。结果表明,富含TiO2的NiTiONPs涂层对多环芳烃(PAHs)具有良好的萃取效率,尤其对苯并[a]芘的萃取选择性优于市售聚二甲基硅氧烷纤维和聚丙烯酸酯纤维。在优化条件下,PAHs的线性范围为0.05~200μg/L,相关系数均大于0.999,检出限为0.012~0.134μg/L。对单支纤维日内和日间分析的相对标准偏差(RSDs)分别为4.0%~5.5%和6.0%~6.8%,使用分批组装的5支纤维分析的RSDs为6.4%~7.6%。实际水样分析的加标回收率为84.5%~111.5%。所制备NiTi纤维至少可重复使用250次以上,重现性好。

The bimetallic oxide nanopores were in situ grown on nickel-titanium( NiTi) fibers by anodization.The anodized fibers were characterized by scanning electron microscopy( SEM) and energy dispersive X-ray spectroscopy( EDS). The Ni Ti fiber with nickel-titanium oxide nanopores( NiTi@ NiTiONPs) based solid phase microextraction was coupled with HPLC-UV to investigate the extraction performance for four types of representative aromatic analytes. The TiO2-rich NiTi @ NiTiONPs fiber showed high extraction efficiency for polycyclic aromatic hydrocarbons( PAHs). In particular,this fiber exhibited better extraction selectivity for B[a]p than the commercial PDMS and PA fibers. The experimental conditions for the extraction of PAHs were optimized. The proposed method with the NiTi@ NiTiONPs fiber was linear in the ranges of 0. 05-200 μg/L with correlation coefficients above 0. 999. Limits of detection were from 0. 012 μg/L to 0. 134 μg/L and relative standard deviations( RSDs) were below 5. 5% and 6. 8% for intra-day and inter-day analyses of PAHs at the spiking level of 50 μg/L with the single fiber( n = 5),respectively. The proposed method was successfully applied to the enrichment and determination of target PAHs in environmental water samples with the recoveries between 84. 5% and 111. 5%. The NiTi @ NiTiONPs fiber can be used at least 250 times and has good reproducibility.