School of Chemistry and Australian Centre for NanoMedicine, University of New South Wales, Sydney NSW 2052, Australia.
School of Chemical Engineering and Graduate School of Biomedical Engineering, and Australian Centre for NanoMedicine, University of New South Wales, Sydney NSW 2052, Australia.
Anal Chem. 2020 May 19;92(10):6900-6908. doi: 10.1021/acs.analchem.9b05524. Epub 2020 May 6.
We report the development of metal-organic framework (MOF)-based probes for the direct and rapid detection and quantification of perfluorooctanoic acid (PFOA) by mass spectrometry. Four water-resistant MOFs-ZIF-8, UiO-66, MIL88-A, and Tb(BDC)-were coated on poly(dopamine) precoated stainless steel needles and used to rapidly preconcentrate PFOA from water for direct analysis by nanoelectrospray ionization mass spectrometry. The analytical performance of each MOF for detecting PFOA was correlated with both the calculated binding energy of the MOF for PFOA and the relative change in the surface area of the MOF upon exposure to PFOA. MOF-functionalized probes can be used for the rapid (<5 min) and sensitive quantification of PFOA molecules at low ng L levels in environmental water samples (i.e., tap water, rainwater, and seawater) with no sample preparation. The limit of detection of PFOA in ultrapure water was 11.0 ng L. Comparable accuracy to an accredited analytical method was achieved, despite the MOF-functionalized probe approach being ∼40 times quicker and requiring ∼10 times less sample. These features indicate that MOF-coated probes are promising for the direct and rapid monitoring of polyfluorinated substances and other pollutants in the field.
我们开发了基于金属有机骨架（MOF）的探针，可通过质谱法直接、快速地检测和定量全氟辛酸（PFOA）。四种耐水的 MOF-ZIF-8、UiO-66、MIL88-A 和 Tb(BDC)-被涂覆在聚多巴胺预处理的不锈钢针上，用于从水中快速预浓缩 PFOA，然后直接通过纳喷雾电离质谱法进行分析。每种 MOF 检测 PFOA 的分析性能与 MOF 对 PFOA 的计算结合能以及 MOF 暴露于 PFOA 时表面积的相对变化相关。MOF 功能化探针可用于在无需样品制备的情况下，快速（<5 分钟）和灵敏地定量环境水样（即自来水、雨水和海水）中的低 ng L 水平的 PFOA 分子。在超纯水中，PFOA 的检出限为 11.0 ng L。尽管 MOF 功能化探针的方法快约 40 倍，所需样品少约 10 倍，但仍达到了与经认可的分析方法相当的准确性。这些特征表明，MOF 涂层探针有望用于现场直接快速监测全氟化合物和其他污染物。
