Data in Table II reveals that DCP had a great effect on
the niosomal formulations. In case of niosomes composed of
Tween 60 (F1–F4) or Brij 35 (F9–F12), the incorporation of
DCP was found to increase the encapsulation efficiency
of gentamicin sulphate. In presence of DCP, equal molarity
of these non-ionic surfactants and cholesterol showed
higher entrapment efficiency than a 1:0.5 molar ratio. This may be due to the fact that cholesterol in the presence of
DCP was more efficiently able to stabilize the structure of
the niosomal membrane in a molar ratio of 1:1 (non-ionic
surfactant: cholesterol) (10). On the other hand, in the
absence of DCP, the formulations exhibited higher entrapment
efficiency within a 1:0.5 molar ratio than 1:1 molar ratio
(non-ionic surfactant: cholesterol). This is possibly attributed
to that an increase in cholesterol ratio may in certain cases
disrupt the regular linear structure of the formed niosomal
membrane (38,39).