title: Determination of cationic surfactants in water samples by their enhanced resonance light scattering with azoviolet.
abstract: A simple assay of cationic surfactants in water samples was developed based on the measurements of enhanced resonance light scattering (RLS). At pH 6.09 and ionic strength 0.03 M, the interactions of azoviolet (AV) with cationic surfactants, including zephiramine (Zeph) and cetyl trimethyl ammonium bromide (CTMAB), result in enhanced RLS signals characterized by the peaks of 470.0, 485.0 and 495.0 nm. The enhanced RLS intensity is proportional to the concentration of cationic surfactant of Zeph in the range of 0.2~6.0x10(-6) M, and to that of CTMAB in the range of 0.4~4.8x10(-6 )M. The limit of determination (3 sigma) is 2.1x10(-8) M and 3.8x10(-8) M for the two surfactants, respectively. Determinations of cationic surfactants in synthetic and tap water samples were successfully made with a recovery of 90.5~108.6%.
authors.affiliation: Institute of Environmental Chemistry, College of Chemistry and Chemical Engineering, Southwest Normal University, Chongqing 400715, PR China.
authors.forename: Chuan Xiao
authors.initials: CX
authors.lastname: Yang
authors.forename: Yuan Fang
authors.initials: YF
authors.lastname: Li
authors.forename: Cheng Zhi
authors.initials: CZ
authors.lastname: Huang
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D001555:Benzene Derivatives / Q000737:chemistry*; D002412:Cations; D005456:Fluorescent Dyes; D008027:Light; D012542:Scattering, Radiation; D013057:Spectrum Analysis; D013501:Surface-Active Agents / Q000032:analysis*; D014867:Water / Q000032:analysis*; D014873:Water Pollutants / Q000032:analysis
chemical_list: D001391:Azo Compounds; D001555:Benzene Derivatives; D002412:Cations; D005456:Fluorescent Dyes; D013501:Surface-Active Agents; D014873:Water Pollutants; C475948:azoviolet; D014867:Water