Background: Ibuprofen (IBU), drug choice of non-steroidal anti-inflammatory
and analgesic, which were formulated in nanosuspension dosage to improve its therapeutic
efficacy. Objective: The aim of the study is to develop and evaluate sustained release ibuprofen
nanosuspension by using Eudragit RL100 polymer using preliminary optimized ratio
of drug to polymer. Method: Nano-precipitation method was used to prepare IBU nanosuspension.
Type of surfactant or stabilizer (Formulation variable) and stirring time (Process variable) were varied
to optimize the formulation. Characterization of the nanosuspension was performed by measuring particles
size, zeta potential, drug entrapment efficiency, drug loading capacity and in-vitro drug release studies.
In vivo pharmacodynamic studies were also carried out on rats. Results: Drug:polymer (1:5) was found to be
effective and optimized ratio for further studies. On the basis of result out of F1-F10 formulations, F2
showed, smallest particle size of 240 nm, zeta potential 21.2 mV, entrapment efficiency of 74.92%. SEM image
showed that the nanoparticles were spherical in shape with smooth surface. FTIR showed no significant interactions
between Eudragit and drug even after encapsulation. In vitro release from the nanosuspension showed
biphasic sustained release the drug action. From the in vivo (anti-inflammatory activity) studies revealed that
prepared nanosuspension sustained its action for longer period of time. Conclusion: Thus, it can be concluded
that IBU loaded nanosuspension considered useful approach for sustained drug release and reduce dosing frequency.