A new derivatisation reaction
for perfluorcaboxylic acids prior to GC/MS analysis.

Monika Strozynska, Manfred Hagmann, Katrin Schuhen

Perfluorocarboxylic acids (PFCAs) are anthropogenic organic compounds with very wide commercial use. This super-surfactants contain carbon-fluorine bonds, which provide their extremely high stability [1]. They have also many disadvantages, like bioaccumulation in the environment [2]. Moreover, the negative effects of PFCAs on human health are widely described [3]. Therefore, their reliable detection in water is imperative.

There are many analytical methods described in the literature using liquid and gas chromatography coupled with mass spectrometry (LC/MS and GC/MS) [4]. All these methods have many advantages but also some drawbacks. It is important to constantly improve the analytical methods and search the new possibilities.

We developed a novel, simple derivatisation reaction for determination of PFCAs (C3-C10) in water by GC/MS. The reaction is based on an acidic catalysed esterification of perfluorinated carboxylic acids to form their silylated derivative. Additionally to the methodologically development in the lab, we analysed various PFCAs in effluents from water treatment plants and well water in Baden-Wuerttemberg (Germany) to confirm the laboratory evaluation. Moreover, the total organic fluorine (TOF) was also measured by GC/MS for those samples. Due to sample preparation simplicity, the presented method can be an alternative for more expensive LC/MS analysis.

[1] Bao J; Liu W; Liu L; Jin Y; Dai J; Ran X; Zhang Z; Tsuda S (2011) Environ. Sci. Technol. 45 (19): 8075–8080. [2] Armitage JM; MacLeod M; Cousins IT (2009) Environ. Sci. Technol 43(15):5830–5836. [3] Stahl T; Mattern D; Brunn H (2011) Env. Sci. Eur. 23(38):1-52. [4] Shafiquea U; Schulze S; Slawik C; Kunz S; Paschke A; Schüürmann G (2017) Anal. Chim. Acta 949:8-11.