What is the Difference Between True and Apparent Partition Coefficient?

The true and apparent partition coefficients are used in pharmaceutical chemistry to describe the distribution of a drug through a system. The key difference between the two lies in the form of the drug they represent.

• True Partition Coefficient: This refers to the ratio of concentrations of un-ionized species of a compound in a mixture of two immiscible phases, such as octanol and water. It gives the distribution of the drug in its unionized state.
• Apparent Partition Coefficient: This coefficient includes all ionized and unionized forms of the solute. It is the ratio of the concentration of the drug in the organic phase to the total drug in the water phase.

In summary, the true partition coefficient represents the distribution of a drug in its unionized state, while the apparent partition coefficient takes into account both ionized and unionized forms of the drug.

Comparative Table: True vs Apparent Partition Coefficient

The difference between true and apparent partition coefficients lies in the state of the compound being considered. Here is a summary of the two concepts:

Both true and apparent partition coefficients are used in pharmaceutical chemistry and drug production. They describe the distribution of a drug through the system, with the true partition coefficient giving the distribution of the drug in its unionized state, while the apparent partition coefficient gives the distribution of the drug in its ionized state.