Abstract:
The aim of the study was to formulate and evaluate mucoadhesive in situnasal gel of
rivastigmine tartrate for nose to brain delivery in the treatment of Alzheimer disease.
Two approaches namely, thermo-sensitive and pH sensitive were used for preparation
of in situgel. Thermoreversible in situgel containing pluronic f-127 (17%w/v) and
carbopol 934(0.3%w/v) made by cold method gave the optimum results of clarity,
pH(5), gelling temperature(350C), gel strength(57 sec), mucoadhesive force(218
dyne/cm2), drug content(96.67%), % cumulative drug release (92.71% in 8 hours) and
had no cellular damage as indicated by histological study. The formulation was stable
for 21 days in accelerated conditions. pH induced in situ gel containing carbopol 934
(0.5%w/v) and HPMC K4M(0.25%w/v) gave the optimum results of clarity, pH(5),
gel strength(44 sec), mucoadhesive force(405.73 dyne/cm2), drug content(96.67%), %
cumulative drug release (93.76% in 8 hours) and had no cellular damage as indicated
by histological study. The formulation was stable for 14 days in accelerated
conditions. ANOVA study for both formulation proved the all responses were
significant. The in situ gel prepared by both the approaches showed compatible
results, but since the pH of the mucosa may vary considerably, thermo-sensitive
approach can be considered as more reliable approach. Therefore the thermo-sensitive
will better approach as compared with pH-sensitive. Thus in situ gel delivered via
nasal route could be promising approach for targeting rivastigmine tartrate directly to
brain for treatment of Alzheimer disease.
