چکیده (انگلیسی):

The purpose of this research was to evaluate in vitro
transnasal sustained-release ability of sorbitan monostearate
(SMS) organogels in isopropyl myristate (IM). Organogels
were prepared containing SMS (2.5%-20%) and water (5%-
25%) in IM and analyzed microscopically for phase behavior.
The effect of Tween surfactants on gel strength and in
vitro nasal diffusion of propranolol is reported. The in vitro
nasal release retardant effect of SMS and Tween 20 was
investigated using factorial design. The microscopic changes
in structure of organogel during in vitro nasal diffusion were
studied. The water-holding capacity of SMS organogels in
IM increased with SMS concentration. The release retardant
effect with incorporation of cosurfactant was of the order of
Tween 80 > Tween 60 > Tween 20. Gel strengthening and
increased viscosity were evident with increased concentration
of SMS and Tween 20. The 3-dimensional network of
SMS molecules controls the diffusional drug release. The
organogel system on nasal mucosa during diffusion is
dynamic in nature and changes continuously with the time of
diffusion. The water penetration in the organogel network
results in percolation and emulsification of organogel, thus
affecting the release. Organogels provided an effective barrier
for diffusion of propranolol. The surface epithelium lining
and the granular cellular structure of treated nasal mucosa
were intact.