caa a22 4500 445880740 CHVBK 20180317145542.0 cr unu---uuuuu 170323e20110601xx s 000 0 eng 10.1007/s00604-011-0579-2 doi (NATIONALLICENCE)springer-10.1007/s00604-011-0579-2 Novel method for in-situ surfactant-based solid-phase extraction: application to the determination of Co(II) and Ni(II) in aqueous samples [Elektronische Daten] [Seyed Yousefi, Farzaneh Shemirani] We report on a completely new kind of solid phase extraction which we term in-situ surfactant-based solid-phase extraction (ISS-SPE). It represents a simple and rapid method for extraction from aqueous samples and preconcentration of compounds containing hydrophobic (alkyl) groups. A cationic surfactant containing alkyl chain is dissolved in the aqueous sample. Following the addition of hexafluorophosphate (HFP; an ion-pairing anion), solutions turn cloudy due to the interaction between the surfactant and the HFP ion. This is due to the formation of fine solid particles composed of the HFP salt of the cationic surfactant. The alkyl groups of the surfactant in the solid particles strongly interact with hydrophobic groups of analytes and become bound. The solid particles are centrifuged, and the sedimented particles can be either dissolved in an appropriate organic solvent, or leached with a solvent to recover the absorbed analyte(s). The method presented here has distinct advantages in that the extraction times are short and recoveries are high, probably a result of the formation of very fine particles of large specific surface, and of their good dispersion in the sample solution. The performance of ISS-SPE was demonstrated by extracting chelates of Co(II) and Ni(II) from water samples. Under the optimized conditions, the preconcentration factors are 51 and 45, respectively, and the detection limits are 0.9 and 0.6μgL−1. The method was validated by the analysis of a certified reference material and by comparing results with those obtained by electrothermal AAS. Figure In ISS-SPE method, a cationic surfactant containing alkyl chain is dissolved in aqueous sample. After addition of hexafluorophosphate anion, a cloudy solution is formed due to formation of fine solid particles (surfactant hexafluorophosphate salt). Hydrophobic anaytes can be adsorbed on the alkyl group of the solid particles and extracted. Springer-Verlag, 2011 In-situ surfactant-based solid phase extraction nationallicence Flame atomic absorption spectrometry nationallicence Aqueous sample nationallicence Nickel and cobalt nationallicence Yousefi Seyed Waste Management Department, NFCRS, Nuclear Science and Technology Research Institute, P.O.BOX11365/8486, Tehran, Iran aut Shemirani Farzaneh School of Chemistry, University College of Science, University of Tehran, Tehran, Iran aut Microchimica Acta Springer Vienna 173/3-4(2011-06-01), 415-421 0026-3672 173:3-4<415 2011 173 604 https://doi.org/10.1007/s00604-011-0579-2 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00604-011-0579-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Yousefi Seyed Waste Management Department, NFCRS, Nuclear Science and Technology Research Institute, P.O.BOX11365/8486, Tehran, Iran aut NATIONALLICENCE 700 1- Shemirani Farzaneh School of Chemistry, University College of Science, University of Tehran, Tehran, Iran aut NATIONALLICENCE 773 0- Microchimica Acta Springer Vienna 173/3-4(2011-06-01), 415-421 0026-3672 173:3-4<415 2011 173 604 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer