Question

Describe the relationship between molecular charge and solubility in organic or aqueous media. Why is this relationship important for understanding drug absorption?

Why is methyl salicylate so easily absorbed through the skin?

Answer 1

Charge iones dissolved readily in water and porlar solvents because these solvents are able to form many ion-dipole interactions, the energy from which is more than enough to make up for energy required to break up the ion-ion interactions in the salts.

Drug absorption is analogue to the biomolecules. Because water is the biological solvent, most biological organic molecules, in order to maintain water-solubility, contain one or more charged functional groups.

Methyl Sacicylate has the ability to dissolve in the non-polar layers in the skin, and also can go into the aqueous phase inside the tissue, thats why in can penetrate easily the skin.