Detection and quantification of fluorinated pollutants Fluorine NMR – FLUOVIAL

Fluorine is a light and common element, but there is nearly no fluorine metabolism in any living organism. Because of the extreme chemical resistance of fluorinated molecules its use in man-made products is common, and fluorine is present in perfluorinated polymers, in nearly 50% of phytosanitary products and in many pharmaceutical drugs, including 3 in the top ten best sellers, Prozac (anti-depressive), Ciflox (antibiotics) and Nifluril (anti-inflammatory). Therefore, fluorinated compounds appears in many emergent environmental pollutants, in particular as Persistent Organic Pollutant (POP). For instance, perfluorooctanesulfonic acid (PFOS) a fluorosurfactant used in many water repellent products and known as endocrine disruptor. This is a major public health issue (Rapport de l’AFSSA, 2010), while fluorinated molecules are difficult to detect by classical means.

Nowadays to evaluate the presence of fluorinated pollutants in the environment or in food, the most common technique is liquid chromatography coupled to mass spectrometry (GC/MS, LC/MS-MS). This approach presents an excellent sensitivity but also some disadvantages. As the need of standards, targeted molecule analyses and solid phase extraction which implies treatments that can alter the sample content. As an alternative and complementary approach, we intend to develop and improve fluorine NMR.

Fluorine provides an efficient and sensitive method to analyse fluorinated molecules. With a 100% abundance and a high resonance frequency, fluorine spectroscopy sensitivity is usually better than hydrogen. NMR is a non-destructive method that allows to measure the sample on its native state without any physical and chemical modification.?The FLUOVIAL project aims to develop a better theoretical and experimental understanding of fluorine NMR spectroscopy, in order harness its analytical capacities in a realistic manner. By developing optimized acquisition sequences in order to increase the overall sensitivity; by carefully studying the sample preparation and the possible fluorine sources of pollution; by the development of new data processing approaches, and adapted denoising algorithms, we aim at developing a method, able to detect organic fluorine, to identify the detected molecules, and to quantify faithfully the amount of each compound. We will also implement machine learning approaches for chemical shifts analysis, for more accurate assignment and automated identification of the compounds present in the samples. All these developments will help to the implementation of an automatic processing pipeline and to establish robust procedures for fluorinated pollutants monitoring.

The FLUOVIAL project is a joint project between the NMR team in the IGBMC laboratory, and the CASC4DE SME, both located in Strasbourg. Pushing the limits of fluorine NMR and its application, we aim at creating a robust analytical method to detect, identify, and quantify fluorinated pollutants of human origin in water effluents, environment and food. This new tool would allow the monitoring of toxic fluorinated compounds, such as the perfluorinated PFOA and PFOS, which get currently unnoticed because of the lack of a reliable detection method. Implemented as an autonomous and ready to use procedure, applicable by most equipped analytical laboratory, this tool will actively be marketed and deployed by the CASC4DE SME.