环境水体中全氟辛烷磺酰氟及其磺酸盐的色谱质谱一体化检测

Perfluorooctane sulfonyl fluoride (PFOSF) is a main precursor of environmentally ubiquitous perfluorooctanesulfonate (PFOS), both of which have been listed as emerging persistent organic pollutants (POPs) in the Stockholm Convention. Its accurate determination, particularly at low concentration levels by liquid chromatography/mass spectrometry (LC/MS) analyses is difficult, due to the lack of chromophore and ionizable functional group. Up to now, it is also currently unknown how much of PFOSF contributed to the burden of environment. The objective of this study is to develop a simple and sensitive derivatization method with reducing agent as derivatization agent for the quantitative analysis of PFOSF from environmental water using LC/MS, upon the introduction of ionizable functional group in the product of perfluorooctane sulfinic acid. With the preparation and purification of perfluorooctane sulfonic acid, standard addition and external standard method for the determination of trace PFOSF in environmental water could be developed. To provide the basis for the effective evaluation of water quality, the content of PFOSF in tap water and its sources, groundwater, and river water samples was investigated. Furthermore, To make clear the conversion relationship of PFOSF in environment, the content of PFOSF in surface water, rain and snow will be also investigated in the meantime. On the basis of similar structure of perfluorooctane sulfinic acid and perfluorooctane sulfonate, the study intends to develop integrated detection method for PFOSF and PFOS in environmental water with HPLC/MS. We believe that the developed methods and their applications on the environmental water provides not only great opportunity for monitoring the environmental fate of PFOSF, but also it can lay the foundation for the orderly supervision of perfluorochemicals.

全氟辛烷磺酰氟(PFOSF)是全氟辛烷磺酸及其盐类(PFOS)的重要生产前体，被斯德哥尔摩公约定义为新的持久性有机污染物。PFOSF因缺乏发色团和可离子化基团，难以采用色谱质谱技术检测，因而对环境的污染程度尚不明晰。本项目通过筛选还原试剂将PFOSF定量衍生为可离子化的全氟辛烷亚磺酸，采用色谱质谱联用技术对其检测，从而间接定量检测PFOSF；制备并纯化全氟辛烷亚磺酸，发展标准加入法和外标法检测环境水体中痕量PFOSF方法。考察自来水及水源、地下水、河水样品中PFOSF的含量；同时段考察PFOSF在地表水、雨水、雪水中的含量；阐明其含量分布及转换规律。基于全氟辛烷亚磺酸与全氟辛烷磺酸具有相似结构的特征，通过统一样品富集、预处理、色谱质谱检测条件，建立环境水体中PFOSF和PFOS色谱质谱一体化检测方法。本项研究不仅为PFOSF的环境污染提供科学依据，而且可为全氟类物质的有序监管奠定基础。

基于全氟烷基磺酰氟基团具有一定的氧化性，在对甲苯硫酚作用下定量产生还原产物全氟烷基亚磺酸，进而通过检测相应的亚磺酸即可定量检测全氟辛烷磺酰氟（PFOSF）、及其替代品全氟己烷磺酰氟（PFHxSF）、全氟丁基磺酰氟（PFBSF）。首次分离并制备获得了关键还原产物亚磺酸。以制备的亚磺酸为对照样品，以C13标记的全氟辛烷磺酸（PFOSI）为内标，通过外标法建立了水体中PFOSF的LC-MS/MS定量检测方法。方法检测限和定量限分别为0.02ng/L与0.1ng/L，线性范围0.5-100ng/L，准确度达99-106%，加标回收率为83-105%，将方法应用于70份水体样品中的PFOSF进行了定量分析研究，含量在0.16 - 66 ng/L的范围内。对雨水及雪水样本进行检测，其中的含量低于检出限。发展了标准加入法测定水体中PFOSF及PFOSI的一体化检测方法，并对来自浙江省杭州市及周边的共计60份水体样品中的PFOSF进行了定量分析研究，所有样品均有一定浓度的PFOSF被检出，其浓度处在2 - 50 ng/L的范围内；并探讨了污水处理过程中PFOSF的变化情况。该方法将为有效评估水质提供依据，为环境水体中PFOSF的监管与监测奠定基础。.采用对甲苯硫酚作为衍生化试剂，结合标准加入法建立了土壤中PFOSF及 PFHxSF及其磺酸的LC-MS/MS一体化定量检测方法。方法在10-500 ng/L的范围内线性良好，线性相关系数R2>0.99。通过与亚磺酸对照品对比，验证了痕量PFOSF和PFHxSF的衍生效率分别为98%和72%。方法应用于湖北武汉市废弃的氟化工厂环境土壤样本分析，其中PFOSF和PFHxSF 的含量分别为2.74-357.08 ng g-1 和0.23-26.51 ng g-1。该方法将为环境土壤中PFOSF的监管与监测奠定基础。.采用荧光滴定的方法结合基质辅助激光解吸质谱证实全氟烷基磺酰氟与人血清白蛋白的作用类型为非共价结合。探讨了PFOSF、PFHxSF、PHBSF对含巯基的谷胱甘肽的氧化还原反应。结果表明三种磺酰氟均可致使含巯基的多肽之间形成以二硫键键合的二聚体产物。此外，考察了三类磺酰氟与含谷胱甘肽肝微粒体的作用，均可产生全氟烷基亚磺酸产物，表明该类化合物可对生物体产生潜在的氧化毒性。