Micellar Solubility and Micelle/Water Partitioning of Polychlorinated Biphenyls in Solutions of Sodium Dodecyl Sulfate

Abstract

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Solubility and micelle-water partitioning of polychlorinated biphenyls in solutions of bile salt micelles

“…This observation is in agreement with the results of studies with artificial surfactants [20,23]. Results from Laher and Barrowman indicate that besides expanding the micellar volume of TC by increasing the bile salt concentration also addition of lipids, thus producing larger mixed micelles, increases the solubility capacity of bile salt micelles [ 15].…”

“…Constant micelle/water partition coefficients over a wide range of micellar concentrations agree with earlier observations on SDS micelles and with observations by Park and Jaff on an anionic surfactant [23,29]. The systematically higher log Kin, values for hydrophobic compounds in TDC solutions compared to the TC solutions might be explained by the more hydrophobic character of TDC compared to TC as expressed by its lower CMC and a higher RP-HPLC retention index [16].…”

“…The presence of dissolved electrolytes in the buffer under the experimental conditions does not seem to have a major influence on the solubilities of the hydropliobic chemicals used in this study. Below the CMC a small enhancement of solubility is seen for these extremely hydrophobic chemicals probably due to an increasing concentration of organic monomers, a phenomenon that we described previously for PCBs in solutions of Sodium Dodecyl Sulphate (SDS) and that was also observed by Kile for DDT (with a log Kow of 6.19) in solutions of non ionics [23,28].…”

“…An extended description of the experimental procedures is published elsewhere [23], but in short the applied method was as follows. Sufficient amounts of the PCBs were dissolved in pentane and added to the chromosorb.…”

“…Solutions consist of bile salt in a phosphate buffer of 0.02 M KH:PO4 at physiological NaC1 concentration of 0.15 M with pH=7. Experiments were conducted in triplo at 25±0.5°C and the vials were stirred continuously during 96 hours which proved to be sufficient to reach equilibrium [23]. Recoveries of the coating, rinsing mid filtering procedure showed to be bereeeen 81% and 104% depending on the PCB congener.…”