On monolayer penetration

Abstract

The techniques used for the study of the penetration phenomenon have been discussed in the light of recent work, and a new method of investigation, based on monolayer expansion and using the automatic compensating balance, is described. Two processes have been found to occur, solution and complex formation. For the two systems investigated, cholesterol—sodium cetyl sulfate and cholesterol—saponin, a 1:1 association between monolayer and water—soluble compounds occurs. The cause of the very slow variation in pressure in mixed films has been found to be due to a solution process of the injected molecules into the monolayer. The technique has also been shown to be applicable to the study of tricomplex films. It has also been found that the interaction can be sensitized or partially prevented.