title: HPLC analysis of aliphatic sulfonate surfactants using ion-pair detection.
abstract: A method was developed for the analysis of a number of surfactants which contained no UV-chromophores, using RP-HPLC with Indirect Photometric Detection, IPD. Pyridinium salts such as N-methylpyridinium iodide, N-methyl-2,2'-dipyridinium iodide and N,N'-dimethyl-2,2'-dipyridinium diiodide, were used as the visualization reagents, forming ion-pair complexes with the sulfonate surfactants. This allowed ordinary UV-detection. N-methylpyridinium iodide proved to be a suitable reagent, both with respect to ease of preparation and response. The eluents consisted of mixtures of acetonitrile and water, being 0.1 - 0.25 mM with respect to pyridinium salt. The method was sensitive and exhibited good signal to noise ratios, as well as linear responses over a wide concentration range. All of the analyzed surfactants were separated, including the diastereomeric forms of some of the surfactants.
authors.affiliation: Department of Chemistry, Norwegian University of Science and Technology, N-7491 Trondheim, Norway.
authors.forename: Marek
authors.initials: M
authors.lastname: Zahrobsky
authors.forename: Davide
authors.initials: D
authors.lastname: Camporese
authors.forename: Øystein
authors.initials: Ø
authors.lastname: Rist
authors.forename: Per H J
authors.initials: PH
authors.lastname: Carlsen
mesh_terms: D000476:Alkanesulfonates / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D010783:Photometry; D011726:Pyridinium Compounds / Q000737:chemistry; D013501:Surface-Active Agents / Q000032:analysis*; D013997:Time Factors
chemical_list: D000476:Alkanesulfonates; D011726:Pyridinium Compounds; D013501:Surface-Active Agents; C014677:1-methylpyridinium