摘要
A novel solid-phase extraction(SPE)strategy based on polypyrrole(Ppy)nanofibers was developed for the determination of trace methotrexate and its polyglutamate metabolites(MTXs)in hospital effluents.Ppy was coated on the surface of electrospun polystyrene nanofibers by in situ oxidative polymerization to form Ppy electrospun nanofibers.The mechanism of adsorption on MTXs was explored through static adsorption studies.The MTX contents,after extraction,were determined by liquid chromatography-tandem mass spectrometry analysis.Results show that the physical/chemical adsorption of targets occurs on the surface of Ppy nanofibers,which is most likely dominated by multiple adsorptions and heterogeneous adsorption sites.Ppy nanofibers exhibit satisfying extraction performance.The content of targets detected in medical wastewater samples ranges from 21 to 2908 ng/L.The novel strategy based on Ppy nanofiber SPE can extract trace MTXs effectively,guarantee analytical accuracy,and circumvent the storage and transportation of water samples during on-site sampling operations.
为实现医疗废水中甲氨蝶呤及其聚谷氨酸代谢物(MTXs)的痕量检测,基于聚吡咯(Ppy)纳米纤维提出了一种新的固相萃取前处理方法.采用原位氧化聚合法,将Ppy包覆在电纺PS纳米纤维表面,形成Ppy电纺纳米纤维.通过静态吸附研究,探索其对于MTXs吸附的作用机制.萃取完成后采用液相色谱-质谱联用(LC-MS/MS)技术检测MTXs浓度.结果表明,目标物可能在Ppy表面发生物理/化学的多次吸附,且吸附位点不均匀.Ppy对于MTXs展现出优良的提取性能,医疗废水样品中目标物检测浓度为21~2908 ng/L.基于Ppy纳米纤维固相萃取的前处理方法能够有效萃取痕量MTXs,保证研究分析精度,可现场采样操作,避免水样的储存和运输.
基金
The National Natural Science Foundation of China(No.82173575)。
