Partition coefficient n-octanol-water

Breindl, A., Beck, B., Qark, T., Glen, R. C. Prediction of the n-octanol/water partition coefficient, log P, using a combination of semiempirical MO-calculations and a neural network. J. Mol. Model. 1997, 3, 142-155. 

Gombar, V. K., Enslein, K. Assessment of n-octanol/water partition coefficient when is the assessment reliable. J. Chem. Inf Comput. Sci. 1996, 36, 1127-1134. 

The following physico-chemical properties of the analyte(s) are important in method development considerations vapor pressure, ultraviolet (UV) absorption spectrum, solubility in water and in solvents, dissociation constant(s), n-octanol/water partition coefficient, stability vs hydrolysis and possible thermal, photo- or chemical degradation. These valuable data enable the analytical chemist to develop the most promising analytical approach, drawing from the literature and from his or her experience with related analytical problems, as exemplified below. Gas chromatography (GC) methods, for example, require a measurable vapor pressure and a certain thermal stability as the analytes move as vaporized molecules within the mobile phase. On the other hand, compounds that have a high vapor pressure will require careful extract concentration by evaporation of volatile solvents. 

Water solubility, dissociation constant(s) and n-octanol/water partition coefficients allow one to predict how an analyte may behave on normal-phase (NP), reversed-phase (RP), or ion-exchange solid-phase extraction (SPE) for sample enrichment and cleanup. 

Kristi, A. Tukker, J. J., Negative correlation of n-octanol/water partition coefficient and transport of some guanine derivatives through rat jejunum in vitro, Pharm. Res. 15, 499-501 (1998). 

In this model, one can argue that a peptide must have both an affinity for the interface (favorable n-octanol partition coefficient) and small desolvation energy (favorable A log PC) in order to efficiently cross a cell membrane. On the other hand, this model also predicts that a peptide with a large n-octanol/water partition coefficient and large desolvation energy, due to a significant number of polar groups, should adsorb and remain at the membrane interface. Both of these predicted events have been observed in the laboratory. 

Burkhard, L. P, Kuehl, D. W., Veith G. D. (1985c) Evaluation of reversed phase liquid chromatograph/mass spectrometry for estimation of n-octanol/water partition coefficients of organic chemicals. Chemosphere 14, 1551-1560. 

Yoshida, K., Shigeoka, T., Yamauchi, F. (1983) Relationship between molar refraction and n-octanol/water partition coefficient. Ecotox. Environ. Saf. 7, 558-565. 

Geyer, H.J., Politzki, G., Freitag, D. (1984) Prediction of ecotoxicological behaviour of chemicals relationship between n-octanol/water partition coefficient and bioaccumulation of organic chemicals by alga chlorella. Chemosphere 13(2), 269-284. 

De Maagd, P.G.-J., ten Hulscher, T.E.M., Van den Heuvel, H., Opperhuizen, A., Sijm, D.T.H.M. (1998) Physicochemical properties of polycyclic aromatic hydrocarbons aqueous solubilities, n-octanol/water partition coefficients, and Henry s law constants. Environ. Toxicol. Chem. 17, 252-257. 

Isnard, P., Lambert, S. (1989) Aqueous solubility and n-octanol/water partition coefficient correlations. Chemosphere 18, 1837-1853. 

Kishi, H., Hashimoto, Y. (1989) Evaluation of the procedures for the measurements of water solubility and n-octanol/water partition coefficient of chemicals results of a ring test in Japan. Chemosphere 18(9/10), 1749-1759. 

Lei, Y.D., Wania, F., Shiu, W.Y., Boocock, G.B. (2000) HPLC-based method for estimating the temperature dependence of n-octanol-water partition coefficients. J. Chem. Eng. Data 45, 738-742. 

Wang, L., Wang, X., Xu, O., Tian, L. (1986) Determination of the n-octanol/water partition coefficients of polycyclic aromatic hydrocarbons by HPLC and estimation of their aqueous solubilities. Huanjing Kexue Xuebao 6, 491 497. 

J.C. Kraak, H.H. van Rooij, and J.L.G. Thus, Reversed-phase ion-pair systems for the prediction of n-octanol/water partition coefficients of basic compounds by high-performance liquid chromatography , J. Chromatogr., 1986, 352,455. 

Boto, P., Moreau, G., and Vandycke, C. Molecular structures perception, autocorrelation descriptor and SAR studies. System of atomic contributions for the calculation of n-octanol/water partition coefficients, Eur.J.Med. Chem.-Chim. Then, 19 71-78, 1984. 

Burkhard, L.P. and Kuehl, D.W. n-Octanol/water partition coefficients by reverse phase liquid chromatography/mass spectrometry for eight tetrachlorinated planar molecules, Chemosphere, 15(2) 163-167,1986. 

Wildlife International. Determination of the n-octanol/water partition coefficient of tetrabromobisphneol A. Wildlife International Ltd., Procet Nuttrber 4-129, 2001. 

Molecular connectivity indices are desirable as potential explanatory variables because they can be calculated for a nominal cost (fractions of a second by computer) and they describe fundamental relationships about chemical structure. That Is, they describe how non-hydrogen atoms of a molecule are "connected". Here we are most concerned with the statistical properties of molecular connectivity Indices for a large set of chemicals In TSCA and the presentation of the results of multivariate analyses using these Indices as explanatory variables to understand several properties important to environmental chemists. We will focus on two properties for which we have a relatively large data base (1) biodegradation as measured by the percentage of theoretical 5-day biochemical oxygen demand (B0D)( 11), and (2) n-octanol/water partition coefficient or hereafter termed log P (12). 

The logarithm of the n-octanol/water partition coefficient (log Kow is a useful preliminary indicator of the bioconcentration potential of a compound. The calculated log K values for 1,3-DNB and 1,3,5-TNB are 1.52 and 1.18 (Deneer et al. 1987), respectively, suggesting a low potential for bioaccumulation. An experimental bioconcentration factor (BCF) of 1,3-DNB for the guppy, Poecilia reticulata, was reported to be 74.13 (Deneer et al. 1987). This BCF indicates that bioaccumulation in aquatic organisms is not an important fate process. BCF data were not located for 1,3,5-TNB. 

De Voogt P, Govers H. 1986. Structural and chromatographic predictors of n-octanol/water partition coefficients. Chemosphere 15 1467-1472. 

Herbert, B. J., and J. G. Dorsey, n-Octanol-water partition coefficient estimation by micellar electrokinetic capillary chromatography , Anal. Chem., 67,744-749 (1995). 

To estimate the n-octanol/water partition coefficient using QPPRs (Section 13.2)... 

Isnard, P., and S. Lambert, Aqueous Solubility and n-Octanol/Water Partition Coefficient Correlations. Chemosphere, 1989 18, 1837-1853. 

Broto, P., G. Moreau, and C. Vandycke, Molecular Structure Perception, Autocorrelation Descriptor and SAR Studies. System of Atomic Contributions for the Calculation of the n-Octanol/Water Partition Coefficients. Eur. J. Med. Chertu-Chim. Then, 1984 19,71-78. 

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