Partitioning Thermodynamics of Selected Endocrine Disruptors between Water and Synthetic Membrane Vesicles: Effects of Membrane Compositions
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- 作者：Jung-Hwan Kwon ; Howard M. Liljestrand ; Lynn E. Katz
- 刊名：Environmental Science & Technology
- 出版年：2007
- 出版时间：June 1, 2007
- 年：2007
- 卷：41
- 期：11
- 页码：4011 - 4018
- 全文大小：283K
- 年卷期：v.41,no.11(June 1, 2007)
- ISSN：1520-5851
文摘
The thermodynamics of partitioning of selected endocrinedisruptors between water and synthetic membranevesicles were investigated. For most of the chemicalsinvestigated, partitioning is dominated by the enthalpychange for unsaturated lipid membrane vesicles and bythe entropy contribution for saturated lipid membrane vesicles.The contribution of the entropy terms in determining the free-energy change becomes more important comparedwith the enthalpy terms with increased branching ofp-substituted phenols. These results suggest that thethermal energy required for and the entropy gain associatedwith the creation of the cavity in the lipid bilayer is ofcritical importance in differentiating the process from1-octanol/water partitioning. In addition, partitioningthermodynamics are significantly influenced by cholesterolcontent in the lipid membranes. Results of the presentstudy and those in the literature suggest that partitioningprocesses significantly depend on the physical state of thelipid membranes and log KOW-based quantitative structure-activity relationships should be carefully applied forpredicting bioconcentration by considering lipid compositions.