Simultaneous Determination of Anionic, Amphoteric and Cationic Surfactants Mixtures in Surface Water

A simple, reliable and accurate HPLC/CAD method was developed for the determination of anionic (sodium dioctyl sulfosuccinate and sodium 1-dodecane sulfonate), amphoteric (CHAPS (3-[(3-Cholamidopropyl) dimethylammonium]-1-propanesulfonate hydrate)) and cationic (benzethonium chloride) surfactants mixture from surface water samples. The chromatographic analysis was performed on an Acclaim Surfactant Plus (150 x 3.0 mm, 3 mu m d.p.) column acquired from Thermo Scientific, kept at 30 degrees C. All experiments were performed in gradient elution conditions at a flow-rate of 0.6 mL/min. Mobile phase composition was a mixture of acetonitrile (A) and 0.1 M ammonium acetate solution acidified to pH 5 with acetic acid (B). The limit of detection (LD) were 20 mu g/L for anionic surfactants and 30 mu g/L for cationic and amphoteric surfactants. The calibration curves were linear between 15 mg/L - 110 mg/L, with R-2 values above 0.992 for all surfactants. Solid phase extraction (SPE) using polymeric (Strata X) cartridges has been applied to extract and concentrate the target analytes from the synthetic samples. Surfactants recoveries after SPE procedure were situated between 91.5 divided by 94.6%. Intra-day and inter-day precision (RSD%) were situated between 4.0 divided by 7.7% and 7.5 divided by 11.7%, respectively. Limit of quantitation (LQ) was lower than 80 mu g/L for anionic surfactants and 90 mu g/L for cationic and 100 mu g/L for amphoteric surfactants. The new sensitive and selective HPLC/CAD developed method allows simultaneous determination of anionic, amphoteric and cationic surfactants mixture from environmental samples (surface water).