What factors affect partition coefficient?

The greater the solubility of a substance, the higher its partition coefficient, and the higher the partition coefficient, the higher the permeability of the membrane to that particular substance.

How does the partition coefficient affect the solubility of the drug?

A partition coefficient is simply the ratio of the concentration of anesthetic in one phase or solvent compared to another. The coefficients of most clinical relevance are the blood:gas and oil:gas partition coefficients. The greater the blood:gas partition coefficient, the greater the solubility in blood.

How does distribution ratio vary with pH?

The distribution constant is pH dependent and the term logD is used to reflect the pH dependent lipophilicity of a drug. The lower the pH of an aqueous solution, the further to the left is the position of equilibrium, i.e. increasing [drug molecule]water and decreasing [drug ion]water.

How is the apparent partition coefficient related to pH?

Apparent partition coefficient takes into account the ionization of the substance and is dependent on pH. The acid dissociation constant (Ka), describes the dissociation of an acid; the higher the Ka, the higher the acid dissociation.

Which is the correct definition of partition coefficient?

A partition coefficient is the ratio of the concentration of a substance in one medium or phase (C1) to the concentration in a second phase (C2) when the two concentrations are at equilibrium; Patricia Pawson, Sandra Forsyth, in Small Animal Clinical Pharmacology (Second Edition), 2008

Why is the partition coefficient important for drug absorption?

Partition coefficient Importance:  For drug delivery, the lipophilic/hydrophilic balance has been shown to be a contributing factor for the rate and extent of drug absorption.  Since biological membranes are lipoidal in nature the rate of drug transfer for passively absorbed drugs is directly related to the lipophilicity of the molecule. 8 9.

How are partition ratios used in Environmental Science?

Partition coefficients (sometimes referred to as partition ratios) are widely used in environmental science to relate the concentration of a chemical solute in one phase to that in a second phase between which equilibrium applies or is approached.