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1A - Environmental Analytical Methods (MO8/3) LC-MS analysis of alkylphenol ethoxylates: what is. Jonkers, Niels1, De Voogt, Pim1, 1 University of Amsterdam, Amsterdam, The Netherlands, The Netherlands ABSTRACT- Alkylphenol ethoxylates (APEO) are nonionic surfactants used in many industrial applications. Due to the estrogenic activity of some of their metabolites, this group of compounds is of major environmental concern. Although a reasonable amount of monitoring data on APEO is now available, the comparability of these data is often questionable. One reason for this is the fact that APEO consist of several tens of alkyl isomers and ethoxylate oligomers, which complicate the analysis. The non-availability of pure standards further renders quantification more difficult. In many studies, not all APEO members present in the samples are included. For example, in GC analysis, often only A9PEO1, A9PEO2 and nonylphenol are detected. The technique most often used for APEO analysis nowadays is liquid chromatography − mass spectrometry (LC-MS). Within this technique, still a number of different methodologies are possible, using e.g., different LC-MS interfaces, different eluent buffers (resulting in different APEO adduct ions), and different ways of calibration (quantification). In this work, a quantitative comparison is made between several LC-MS methods for APEO, with the goal to establish the most reliable and reproducible quantification method, and to achieve some form of standardization for the analysis of surfactants in the future. Key words: LC-MS, alkylphenol ethoxylates, quantification, quality control |
