<br>使用 19F NMR 研究阳离子碳点与全氟烷基物质和多氟烷基物质 (PFAS) 的缔合,ACS Nanoscience Au

当前位置： X-MOL 学术 › ACS Nanosci. Au › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

使用 19F NMR 研究阳离子碳点与全氟烷基物质和多氟烷基物质 (PFAS) 的缔合
ACS Nanoscience Au ( IF 4.8 ) Pub Date : 2023-08-25 , DOI: 10.1021/acsnanoscienceau.3c00022
Riley E Lewis ₁ , Cheng-Hsin Huang ₁ , Jason C White ₂ , Christy L Haynes ₁

Affiliation

全氟烷基物质和多氟烷基物质（PFAS）因其环境持久性和毒性而备受关注，因此迫切需要修复技术。本研究的重点是确定纳米级聚合碳点是否是 PFAS 的可行吸附剂材料，并开发氟核磁共振波谱 ( ¹⁹ F NMR) 方法来探测碳点和 PFAS 之间在分子尺度上的相互作用。使用支化聚乙烯亚胺合成带正电的碳点（PEI-CD），通过促进静电相互作用来靶向阴离子 PFAS。将 PEI-CD 暴露于全氟辛酸 (PFOA)，以评估其作为 PFAS 吸附剂材料的潜力。暴露于 PFOA 后，PEI-CD 的平均尺寸增加（1.6 ± 0.5 至 7.8 ± 1.8 nm），表面电荷减少（+38.6 ± 1.1 至 +26.4 ± 0.8 mV），这两者都与污染物吸附一致。开发¹⁹ F NMR 方法是为了进一步了解 PEI-CD 对 PFAS 的亲和力，而无需任何复杂的样品制备。在不同的 PEI-CD 浓度下监测 PFOA 峰强度和化学位移的变化，以建立结合曲线并确定化学交换机制。 ¹⁹ F NMR 光谱分析表明 PFOA 和 CD 之间存在缓慢的中间化学交换，证明了高亲和力相互作用。 α-氟的化学位移变化最大，亲和力最高，表明静电相互作用是主要的吸附机制。当暴露于 24-PFAS 混合物时，PEI-CD 表现出对多种分析物的亲和力，对全氟烷基磺酸盐略有偏好。总体而言，本研究表明 PEI-CD 是一种有效的 PFAS 吸附剂材料，并建立¹⁹ F NMR 作为筛选新型吸附剂材料和阐明相互作用机制的合适方法。

"点击查看英文标题和摘要"

Using 19F NMR to Investigate Cationic Carbon Dot Association with Per- and Polyfluoroalkyl Substances (PFAS)

There is much concern about per- and polyfluoroalkyl substances (PFAS) based on their environmental persistence and toxicity, resulting in an urgent need for remediation technologies. This study focused on determining if nanoscale polymeric carbon dots are a viable sorbent material for PFAS and developing fluorine nuclear magnetic resonance spectroscopy (¹⁹F NMR) methods to probe interactions between carbon dots and PFAS at the molecular scale. Positively charged carbon dots (PEI-CDs) were synthesized using branched polyethyleneimine to target anionic PFAS by promoting electrostatic interactions. PEI-CDs were exposed to perfluorooctanoic acid (PFOA) to assess their potential as a PFAS sorbent material. After exposure to PFOA, the average size of the PEI-CDs increased (1.6 ± 0.5 to 7.8 ± 1.8 nm) and the surface charge decreased (+38.6 ± 1.1 to +26.4 ± 0.8 mV), both of which are consistent with contaminant sorption. ¹⁹F NMR methods were developed to gain further insight into PEI-CD affinity toward PFAS without any complex sample preparation. Changes in PFOA peak intensity and chemical shift were monitored at various PEI-CD concentrations to establish binding curves and determine the chemical exchange regime. ¹⁹F NMR spectral analysis indicates slow-intermediate chemical exchange between PFOA and CDs, demonstrating a high-affinity interaction. The α-fluorine had the greatest change in chemical shift and highest affinity, suggesting electrostatic interactions are the dominant sorption mechanism. PEI-CDs demonstrated affinity for a wide range of analytes when exposed to a mixture of 24-PFAS, with a slight preference toward perfluoroalkyl sulfonates. Overall, this study shows that PEI-CDs are an effective PFAS sorbent material and establishes ¹⁹F NMR as a suitable method to screen for novel sorbent materials and elucidate interaction mechanisms.

更新日期：2023-08-25

点击分享查看原文

点击收藏

公开下载

阅读更多本刊新发论文