Fluorescence-Solid Phase Extraction (F-SPE) Platform for Rapid, On-site Detection of PFAS

项目摘要 全氟烷基和多氟烷基物质（PFAS）已成为一类新兴的水污染物 造成严重的环境和健康问题。由于其在工业、军事、 和消防等方面的影响，PFAS已广泛存在于各种水体中。中 全氟辛烷磺酸（PFOS）， 全氟辛酸（PFOA）代表了使用和研究最多的两种PFAS 方面的影响.最近的研究表明，暴露于这些PFAS和许多类型之间存在密切联系。 疾病和健康影响。目前，美国环保局为全氟辛烷磺酸设定的咨询水平， 饮用水中的全氟辛酸为70 ppt（全氟辛烷磺酸和全氟辛酸为0.14和0.17 nM）。电流检测 PFAS主要基于液相色谱-质谱联用（LC-MS）。 然而，成本、占地面积、功率要求和样品制备过程通常不太合理。 与LC-MS技术相关的限制了其在正式实验室之外的部署 设置.特别是对于检测纳摩尔水平的PFAS，LC-MS通常需要 预浓缩前端设备，使分析更加耗时。变得 迫切需要开发一种快速、简单、低成本的传感器技术， 现场检测PFAS。虽然许多化学传感器，如基于荧光的传感器， 调制，已开发用于PFAS的检测，其中大多数还远未达到 对于饮用水分析而言，无论是灵敏度（相对于70 ppt）还是选择性（相对于 常见的化学品，特别是洗涤剂）。 该项目旨在通过开发一种独特的传感器平台来填补这一技术空白， 易于使用，提供灵敏和选择性的全氟辛烷磺酸和全氟辛酸（被选为 代表性PFAS分析物）。该传感器平台是基于高灵敏度和选择性 荧光传感器涂覆到固相萃取（SPE），能够预浓缩 低浓度的分析，从而降低检测限。的组合 在一个平台（即F-SPE）中进行SPE预浓缩和荧光检测， 大大简化和加快了分析过程。此外，F-SPE采用以下原则： SPE固有的可忽略消耗（ND），这将进一步简化分析过程， 从而消除了常规测量通常所需的精确计量样品体积的需要 分析方法 ND依赖于使最小量的样品通过膜，这是检测所需的 分析物提取达到平衡。此时，样品中的分析物浓度 进入和离开膜是相等的。结果，分析物的表面浓度 可以直接与其在样品中的浓度相关，但不再依赖于 通过膜的样品体积。因此，不再需要 计量通过膜的精确样品体积。本文的主要创新在于 将荧光传感器的高灵敏度和选择性与预富集相结合， SPE的性能和ND原理，这将使快速，可靠的检测PFAS在一个简单的， 低成本的方式。 该项目将围绕三个具体目标实施： 具体目标1。对全氟辛烷磺酸选择性荧光团的合成和表面固定 或PFOA到内部制造的SPE磁盘。 具体目标2。评价F-SPE/ND用于全氟辛烷磺酸和全氟辛酸检测。 具体目标3。商业化评估。

Project Summary Per-and polyfluoroalkyl substances (PFAS) have become an emerging class of water pollutants that cause serious environmental and health concerns. Due to their wide use in industry, military, and fire protection, PFAS have been spread and present in all kinds of water bodies. Among the over thousand PFAS ever manufactured and used, perfluorooctanesulfonic (PFOS) and perfluorooctanoic acid (PFOA) represent the top two PFAS used and studied the most for health effects. Recent studies indicate a tight linkage between exposure to these PFAS and many kinds of diseases and health effects. Currently, the advisory level set by the US EPA set for PFOS and PFOA in drinking water is 70 ppt (0.14 and 0.17 nM for PFOS and PFOA). Current detection of PFAS is mostly based on liquid chromatography coupled with mass spectrometry (LC-MS). However, the costs, footprint, power requirements, and sample preparation processes often associated with the LC-MS technologies limit their deployment beyond the formal laboratory setting. Especially for the detection of nanomolar levels of PFAS, LC-MS usually requires a preconcentration frontend device, making the analysis even more time-consuming. It becomes imperative to develop a rapid, simple, and low-cost sensor technology that is more suited for quick onsite detection of PFAS. While many chemical sensors, such as those based on fluorescence modulation, have been developed for the detection of PFAS, most of them are still far from sufficient for potable water analysis regarding either sensitivity (vs. 70 ppt) or selectivity (against the common chemicals, especially detergents). This project aims to fill this technical gap by developing a unique sensor platform that is small and easy to use, offering sensitive and selective infield detection of PFOS and PFOA (selected as the representative PFAS analytes). The sensor platform is based on highly sensitive and selective fluorescence sensors coated onto solid-phase extraction (SPE) capable of preconcentration of low concentrations of analyses, thus lowering the detection limit. The combination of preconcentration of SPE and fluorescence detection in one platform (namely F-SPE) would significantly simplify and speed up the analysis process. Moreover, F-SPE takes the principle of negligible depletion (ND) intrinsic to SPE, which would further simplify the analysis process by eliminating the need to precisely meter the sample volume as typically required for conventional analytical methods. ND relies on passing the minimal amount of sample through the membrane that is required for the analyte extraction to reach equilibrium. At this point, the analyte concentrations in the sample entering and exiting the membrane are equal. As a result, the surface concentration of the analyte can be directly correlated to its concentration in the sample but is no longer dependent on the volume of the sample passed through the membrane. Therefore, it is no longer necessary to meter an exact sample volume through the membrane. The main innovation herein lies in integrating the high sensitivity and selectivity of fluorescence sensors with the preconcentration capability and ND principle of SPE, which will enable quick, reliable detection of PFAS in a simple, low-cost way. The project will be implemented around three specific aims: Specific Aim 1. Synthesis and surface immobilization of fluorophores selective to either PFOS or PFOA to in-house fabricated SPE disks. Specific Aim 2. Evaluation of F-SPE/ND for PFOS and PFOA detection. Specific Aim 3. Commercialization Assessment.