Background: Poor solubility and low dissolution rate limit the work at poorly water-soluble
drugs like Esomeprazole. To overcome this problem, different technologies had to be used but could
not resolve the problem, significantly. The main aim of this patent study was to prepare the nanocrystals
using the evaporative precipitation ultrasonication method in order to improve the dissolution rate
and stability of Esomeprazole (ESM).
Methods: For obtaining the nanocrystals, different nanoformulations were prepared using the pluronic
F-68 in different concentrations, and then the screened formulation was lyophilized in the presence of
two distinct cryoprotectants; mannitol and sucrose. The obtained nanocrystals were characterized for
their re-dispersibility, crystalline state, dissolution behavior, particle size, polydispersibility index and
morphology. Dissolution study of ESM nanocrystals was performed in a buffer solution of pH-7.4, and
compared to that of bulk ESM sample and ESM/pluronic F-68 physical mixture.
Results: Cryoprotectant containing nanocrystals exhibit the re-dispersion in water after the manual
shaking. 5% mannitol containing nanocrystals showed the least polydispersity index (0.42 ± 0.11) and
narrowest particle size (186 ± 12.9 nm). The Powder X-ray Diffraction (PXRD) pattern and differential
scanning calorimeter (DSC) thermograms revealed that the crystalline state of the drug was not
changed after the different physical treatment. Freeze-dried nanocrystals showed a faster dissolution
rate and almost 99.45% of the drug was released within 60 min. However, the bulk drug and a physical
mixture of bulk drug/pluronic F-68 showed only 22.65% and 21.3% of drug release, respectively, after
60 min. This paper reviews the related patents on Esomeprazole Nanocrystals.
Conclusion: The different findings revealed that nanocrystals could be a potential alternate for solving
the dissolution rate and stability issue of ESM like poorly soluble drugs.