From the results, it is obvious tha

From the results, it is obvious that the increase of
cholesterol molar ratio from 1:0.5:0.1 to 1:1:0.1 (non-ionic
surfactant: cholesterol: DCP) markedly reduced the efflux of
the drug from niosomal preparations (F3, F4, F11 and F12),
which is in accordance with its membrane stabilizing ability (40). Cholesterol is known to abolish the gel to liquid phase
transition of niosome systems (35), resulting in niosomes that
are less leaky (36). Therefore, the diffusion of gentamicin
entrapped in the hydrophobic regions of the vesicles would be
expected to occur over a prolonged period of time. On the
contrary to previous results, the increase of cholesterol molar
ratio from 0.5 to 1 slightly increased the efflux of the drug
from DCP free niosomes (F1, F2, F9 and F10).