Submicron-sized particles show adhesiveness when
in contact with surfaces. This property has been
demonstrated for polymeric nanoparticles and for
liposomes. Regarding lipid nanoparticles, it has
been published that approximately 4% of lipid
nanoparticles with a diameter of approximately
200 nm should form theoretically a monolayer
film when c. 4 mg of formulation is applied per
cm2 [9]. Being hydrophobic in character, this
mono-layered film has an occlusive action on the
skin retarding the loss of moisture caused by evaporation.
Experimental verification of moisture barrier
properties has demonstrated the different
degree of occlusion, depending on the size of the
applied particles