ABSTRACT
Before speaking about ‘‘cationic and amphoteric surfactants’’ and analytical methods for them, this group of substances requires a precise definition. The meaning of the word ‘‘surfactant’’ is quite unambiguous and denotes a molecule that-due to its amphiphilic nature-tends to enrich at phase boundaries and that forms micelles above the critical micelle concentration. The word ‘‘cationic,’’ however, implies a positive electrical charge of the molecule; but this is not strictly true for all substances that are normally counted among the cationic surfactants.
