The invention concerns a composition comprising at least a first constituent which is an oligosaccharide of formula (I) containing 3 to 5 oside units and having at least a D-galactose unit bound by an [1-6] bond with a sucrose unit. The invention is characterized in that in said sucrose unit R1, R2, R3, R4, independently of one another represent a hydrogen atom, an alkyl group containing 1 to 10 carbon atoms and optionally having at least an unsaturation, a sulphate function or else an ose and, at least a second constituent which is a molecule positively charged with a physiological pH and stimulating pinocytosis or a molecule stimulating membrane penetration.