Rapid analysis of anionic and cationic surfactants in water by paper spray mass spectrometry

The discharge of wastewater containing surfactants and other industrial pollutants is contaminating the world's water resources which should be taken seriously. This paper describes a paper spray mass spectrometric (PS-MS) method for rapid and quantitative analysis of anionic and cationic surfactants in water samples. Eight cationic surfactants and four anionic surfactants can be simultaneously determined in positive or negative mode without sample pretreatment and chromatographic separation. The PS-MS analysis time was only 10 s. Under optimized conditions, the method presented a suitable linear range (1-80 μg mL^-1, linear regression coefficients (R²) higher than 0.995 for cationic surfactants, R² higher than 0.990 for anionic surfactants), a low limit of detection (0.05-0.35 μg mL^-1 for cationic surfactants and 0.20-0.35 μg mL^-1 for anionic surfactants), and satisfactory recovery values (97.3-106.1%). The method validation indicated that the method precision and accuracy were satisfactory. The results demonstrated that PS-MS is especially suitable for the high-throughput analysis of surfactants in water samples.