Identification and Determination of Nonionic Surfactants by Ultrahigh-Performance Liquid Chromatography–High-Resolution Mass Spectrometry

We proposed a procedure for the identification and determination of nonionic surfactants in natural waters by ultra-HPLC with high-resolution mass spectrometry detection. The main analytical characteristics of the determination of the most common nonionic surfactants—alkylphenol ethoxylates and alkyloxyethoxylates—are found by the proposed method. The main adducts of polymer homologues of the determined surfactants, formed under electrospray ionization, are considered. To extract analytes from natural water samples, we used dispersive liquid–liquid microextraction with a mixture of trichloromethane and acetonitrile. A possibility of the determination of nonionic surfactants by the direct electrospray of a prepared sample into a mass spectrometer is considered. The limits of quantification of surfactants under the selected conditions varied from 0.1 to 0.5 ng/mL; the analytical range was from 1 to 1000 ng/mL. The relative standard deviation of the results did not exceed 15%. The duration of the identification of sample components was 30 min; the determination of the detected analytes took 1 h.