Apparent octanol/water partition coefficients of pentachlorophenol as a function of pH

1982 ◽  
Vol 60 (16) ◽  
pp. 2104-2106 ◽  
Author(s):  
Klaus L. E. Kaiser ◽  
Ilze Valdmanis
Keyword(s):  
Aqueous Solution ◽  
Ionic Strength ◽  
Partition Coefficient ◽  
Linear Function ◽  
Partition Coefficients ◽  
Extreme Values ◽  
Log P ◽  
Water Partition Coefficient ◽  
Non Linear ◽  
Good Agreement

The apparent 1-octanol/water partition coefficient (log PApp) of pentachlorophenol (PCP) varies in non-linear function with pH of the aqueous solution. In the range of pH 1.2 to 13.5 extreme values of log PApp 4.84 at pH 1.2 and log PApp 1.3 at pH 10.5 were observed. In the alkaline regime, log PApp increases strongly with the ionic strength. The ion-corrected partition coefficient of PCP was found to be log P 5.05 in good agreement with literature values.

Determination of Ionization Constant (pKa) and Octanol–Water Partition Coefficient (Log P) of Cyclopiazonic Acid

2005 ◽  
Vol 88 (5) ◽  
pp. 1367-1370 ◽  
Author(s):  
Victor S Sobolev
Keyword(s):  
Partition Coefficient ◽  
Potentiometric Titration ◽  
Ionization Constant ◽  
Cyclopiazonic Acid ◽  
Log P ◽  
Experimental Conditions ◽  
Water Partition Coefficient

Abstract The ionization constant (pKa) and the octanol–water partition coefficient (log P) of the important mycotoxin cyclopiazonic acid (CPA) were determined by means of potentiometric titration, and the lipophilicity profile (log D) was calculated. Under the experimental conditions, pKa of CPA = 2.97 ± 0.09, log P = 3.83 ± 0.10, and log D at pH 7.4 = −0.58.

scholarly journals Tracer Determinations of Human Red Cell Membrane Permeability to Small Nonelectrolytes

1971 ◽  
Vol 58 (3) ◽  
pp. 259-266 ◽  
Author(s):  
David Savitz ◽  
A. K. Solomon
Keyword(s):  
Cell Membrane ◽  
Partition Coefficient ◽  
Cell Membrane Permeability ◽  
Red Cell ◽  
Red Cell Membrane ◽  
Water Partition Coefficient ◽  
Order Of Magnitude ◽  
Red Cell Membranes ◽  
Human Red Cell Membrane ◽  
Good Agreement

A flow system has been used to determine the permeability of human red cell membranes to four small nonelectrolytes labeled with 14C. The permeability coefficients, ω, in units of mol dyne-1 sec-1 x 1015, are: ethylene glycol, 6; urea, 13; formamide, 22; and methanol, 131. The values for urea and formamide are in good agreement with values obtained by Sha'afi, Gary-Bobo, and Solomon by the minimum method. The unusually high value for ω for methanol is ascribed to its solubility in the red cell membrane since its ether: water partition coefficient is 0.14, higher by more than an order of magnitude than the ether: water partition coefficient for water. The other three solutes are hydrophilic and are characterized by values of ω which behave consistently with those of other hydrophilic amides and ureas. The values of ω for the three hydrophilic solutes measured are also consistent with an equivalent pore radius of about 3.5 A in agreement with previous estimates made on the basis of other types of studies.

Rat Tissue and Blood Partition Coefficients for n-Alkanes (C8 to C12)

2005 ◽  
Vol 24 (1) ◽  
pp. 35-41 ◽  
Author(s):  
A. Q. Smith ◽  
J. L. Campbell ◽  
D. A. Keys ◽  
J. W. Fisher
Keyword(s):  
Linear Regression ◽  
Partition Coefficient ◽  
Partition Coefficients ◽  
Important Determinant ◽  
Lipid Solubility ◽  
Rat Tissue ◽  
Good Agreement

Rat tissue:air and blood:air partition coefficients (PCs) for octane, nonane, decane, undecane, and dodecane (n-C8 to n-C12 n-alkanes) were determined by vial equilibration. The blood:air PC values for n-C8 to n-C12 were 3.1, 5.8, 8.1, 20.4, and 24.6, respectively. The lipid solubility of n-alkanes increases with carbon length, suggesting that lipid solubility is an important determinant in describing n-alkane blood:air PC values. The muscle:blood, liver: blood, brain:blood, and fat:blood PC values were octane (1.0, 1.9, 1.4, and 247), nonane (0.8, 1.9, 3.8, and 274), decane (0.9, 2.0, 4.8, and 328), undecane (0.7, 1.5, 1.7, and 529), and dodecane (1.2, 1.9, 19.8, and 671), respectively. The tissue:blood PC values were greatest in fat and the least in muscle. The brain:air PC value for undecane was inconsistent with other n-alkane values. Using the measured partition coefficient values of these n-alkanes, linear regression was used to predict tissue (except brain) and blood:air partition coefficient values for larger n-alkanes, tridecane, tetradecane, pentadecane, hexadecane, and heptadecane (n-C13 to n-C17).Good agreement between measured and predicted tissue:air and blood:air partition coefficient values for n-C8 to n-C12 offer confidence in the partition coefficient predictions for longer chain n-alkanes.

Development of predictive models for silicone rubber–water partition coefficients of hydrophobic organic contaminants

2019 ◽  
Vol 21 (12) ◽  
pp. 2020-2030
Author(s):  
Huichao Sun ◽  
Xianhai Yang ◽  
Xuehua Li ◽  
Xiaochen Jin
Keyword(s):  
Partition Coefficient ◽  
Organic Compounds ◽  
Silicone Rubber ◽  
Predictive Models ◽  
Organic Contaminants ◽  
Partition Coefficients ◽  
Hydrophobic Organic Compounds ◽  
Hydrophobic Organic Contaminants ◽  
Water Partition Coefficient ◽  
Qsar Models

The developed TLSER and QSAR models can be used to predict silicone rubber (passive sampler material)–water partition coefficient (Ksrw) of hydrophobic organic compounds (HOCs).

Evaluation of adsorbability of pesticides in water on powdered activated carbon using octanol-water partition coefficient

1997 ◽  
Vol 35 (7) ◽  
pp. 219-226 ◽  
Author(s):  
Jian-ying Hu ◽  
Takako Aizawa ◽  
Yasumoto Magara
Keyword(s):  
Activated Carbon ◽  
Adsorption Isotherm ◽  
Partition Coefficient ◽  
Partition Coefficients ◽  
Powdered Activated Carbon ◽  
Adsorption Parameters ◽  
Pesticide Concentration ◽  
Water Partition Coefficient ◽  
Pesticides In Water ◽  
High Polarity

The 1-octanol-water partition coefficients (logPow) of seven pesticides, i.e., Hymexazol, methomyl, imidacloprid, thiophanatemethyl, carbaryl, linuron, thiobencarb, were determined by RPHPLC method. The relation between these estimated logPow and adsorption isotherm parameters on powdered activated carbon was studied by correlating their logPow values with the Freundlich adsorption parameters. The adsorption parameter, logk, was found to increase with the increase of logPow for the pesticides examined. The activated carbon amount needed for lowering pesticide concentration from 500 μg/l to 50 μg/l was calculated. The amount of activated carbon needed for hymexazol (logPow, 0.11) was 688.5 mg/l, while that for thiobencarb (logPow, 3.78) was 5.1 mg/l, which suggests that pesticides with a high polarity, i.e., a low Pow, are difficult to remove by powdered activated carbon.

Sign in / Sign up

Export Citation Format

Share Document