Preconcentration of benzalkonium chloride using sodium dodecyl sulfate attached to a strong anion exchange resin

A surfactant-mediated solid phase extraction procedure is applied for the preconcentration of benzalkonium (BA) chloride from a river water sample. Dodecyl sulfate is attached to a strong anion exchange resin and aqueous samples are passed through a column containing this surfactant-resin material. Benzalkonium chloride, a cationic compound very useful in cosmetics and an important fungicide, is adsorbed from the aqueous solution onto the sorbent via hydrophobic and electrostatic interactions. When using traditional silica-based nonpolar sorbents, strong electrostatic interactions between the cationic analyte and the silica surface make elution difficult. Using the presented sorbent, electrostatic attractions occur between the benzalkonium cations and removable dodecyl sulfate anions. Removing this ion pair from the sorbent results in efficient elutions. The results of this solid-phase extraction (SPE) method are presented in terms of various rinse solutions parameters, breakthrough studies and a real river water sample. (c) 2004 Elsevier B.V. All rights reserved.