Background: Irbesarten antagonizes angiotensin II by blocking
AT1 receptors in hypertension.
Objective: To develop hydrophobically modified starch nanoparticles and
to increase the dissolution and bioavailability of Irbesarten.
Methods: The synthesis of palmitic acid grafted maize starch (PAgMS)
using long chain fatty acid was performed by esterification. The formation
of palmitic acid grafted maize starch (PAgMS) was confirmed by FTIR
and NMR study. Particle size measurements, zeta potential, percentage
drug entrapment efficiency were characterized to optimize formulations.
Results: The particle size of formulation shows smaller particle size and high drug entrapment
efficiency. All formulations showed negative zeta potential which results in better
stabilization of the nanoparticles. The Scanning electron microscopy (SEM) results revealed
that Irbesarten was present in amorphous state in the polymer. There was a significant
enhancement of in vitro release (94.75%) of Irbesarten from PAgMS nanoparticles as
compared to pure Irbesarten (20%) in 60 min. Irbesarten loaded palmitic acid grafted maize
starch (PAgMS) nanoparticles showed significant increase (P<0.001) in relative bioavailability
than marketed formulation.
Conclusion: In conclusion, the prepared Irbesartan loaded palmitic acid grafted maize
starch (PAgMS) nanoparticles showed remarkable increase in dissolution rate and hence
bioavailability in rabbit.