Can one component of a mixture penetrate the skin if the whole mixture cannot?

There's a general rule that says that compounds under 500 dalton are able to penetrate the skin without any special vehicle (such as ethanol).


I've started using castor oil, which contains different acids that are believed to be good for the skin (not discussing this here now). The oil is very thick, and each acid has different molecular weight. I'm mostly interested in ricinoleic acid, which has about 300 dalton.


If I were to apply this bare oil on my skin, would it be a correct to think that some acids would penetrate the skin and some others wouldn't (because of the 500 dalton rule), assuming this oil didn't have any special treatment (except, well, the process of extracting the oil itself)?


