Objective: In the present study, the utilization of a novel biocompatible and biodegradable
Methotrexate controlled release injectable formulation is established. The drug delivery vehicle used
is an autogelling pH sensitive formulation, which is based on the natural biopolymer chitosan.
Methods: Chitosan/glyceryl monooleate (C/GMO) solution was prepared in 0.33 M citric acid with
gentle stirring. The weighed quantity of Drug and Chitosan in the required concentration was stirred
with an appropriate quantity of 0.33 M Citric acid for 3 hours. Further, this solution was cooled to
4oC. Then, to this cooled Chitosan and Drug solution, the desired amount of Glycerol Monooleate
was added dropwise with constant stirring to obtain a clear homogenous system. Moreover, it was filtered
by membrane filtration using the cellulose membrane. Finally, the prepared pH sensitive formulations
were sterilized by autoclaving.
Results: The drug release of the final formulation as cumulative percent drug release was found out to
be 80.93%, 95.78%, 75.86%, 93.58% and 84.10% for formulation F1, F2, F3, F4 and F5 respectively
after 8 hours. The in vitro drug release study had shown that the formulation F2 had better-sustained
effect than other existing pH-induced formulations.
Conclusion: All these findings showed that chitosan/GMO gel was found to be safe, effective, homogeneous
and stable injectable formulation for sustained delivery of Methotrexate and presented an approach
for the striking technology offering the platform for the delivery of other clinically significant