Extraction and derivatization for perfluorocarboxylic acids in liquid and solid matrices: A review

Perfluorocarboxylic acids (PFCAs) are anthropogenic organic compounds with very unique and useful properties, for example, surfactant properties and immense stability. These substances are nowadays widely used in many industrial and consumer products. Their presence in human, biological, and environmental samples throughout the world has been described in numerous research articles. Unfortunately, PFCAs have also been found to be toxic, persistent, and bioaccumulative. Therefore, there is a great need for a constant and reliable detection of PFCAs in various matrices. Nowadays, the analysis based on liquid chromatography coupled to mass spectrometry (LC-MS and LC-MS/MS) is considered to be the method of choice. Determination of PFCAs by gas chromatography (GC) is not so well established as the LC methods. Nevertheless, GC can be considered as a complementary method, which can help to gain more reliable results and to crosscheck the LC analysis. The sample preparation is crucial, but also a time- and cost-consuming part of the PFCAs analysis. This article reviews the two most important sample preparation steps for the analysis of PFCAs: extraction and derivatization. It discusses the possible enrichment of PFCA using various extraction techniques used both for LC and GC. The derivatizing agents used prior to the GC analysis are described. The sample pretreatment as well as the most relevant problems and the sensitivity of the methods are presented. Moreover, advantages and disadvantages of LC and GC analysis are discussed.