Cationic gemini pyrrolidinium surfactants based sweeping-micellar electrokinetic chromatography for simultaneous detection of nine organic pollutants in environmental water

A series of novel cationic gemini surfactants with pyrrolidinium head groups, 1,1′-(butane-1,s-alkyl) bis (1-alkylpyrrolidinium) (C n -4-C n PB, n   =   12, 14, 16), were employed as carriers in sweeping–micellar electrokinetic chromatography (sweeping-MEKC) for simultaneous detection of nine organic water pollutants , including polycyclic aromatic hydrocarbons, sulfonamides and steroids. The sweeping and separation conditions were optimized. C n -4-C n PB ( n   =   12, 14, 16) were compared with cetyltrimethylammonium bromide (CTAB) in terms of their abilities to preconcentrate and separate the nine analytes. Under the optimized conditions, the sensitivity enhancement factors based on the peak height (SEFs Height ) were ca. 310–580 of C 16 -4-C 16 PB, which were higher than those of C 14 -4-C 14 PB (120–290) and C 12 -4-C 12 PB (110–160). Meanwhile, the SEFs Height of C 16 -4-C 16 PB were higher than those of 30% (v/v) methanol-modified CTAB (140–320). The C 16 -4-C 16 PB based sweeping-MEKC, coupled with offline solid phase extraction and UV detection (228   nm), was used to analyze spiked environmental water samples. The nine analytes were successfully separated and detected. The limit of detection (S/N   =   3) was in range of 2.79–3.76   ng/mL, and the recovery ranged from 70.8% to 95.5% with the RSDs less than 9.89%. This study confirms that the C 16 -4-C 16 PB based sweeping-MEKC has significant advantages over the CTAB based sweeping-MEKC and it is a promising method for sensitive and simultaneous detection of polycyclic aromatic hydrocarbons, sulfonamides and steroids in environmental water samples.