2 research outputs found
Influence of process variables on the properties of simvastatin self-emulsifying granules obtained through high shear wet granulation
Improvements of the oral bioavailability of lipophilic drugs can be obtained using lipidic formulations such as the
self-emulsifying drug delivery systems. The high shear wet granulation (HSWG), using microemulsions as
binder, is a viable process to produce self-emulsifying granules. However only few information are present in
the literature on the effect of process variables on the properties of the granules obtained with these binders.
Consequently, this article compares the effects of some relevant experimental variables (impeller speed and
massing time) on thefinal technological and pharmaceutical properties of the granules produced using simple
water, or alternatively, a microemulsion as binder and containing simvastatin (SV) as model drug. The effects
of the variables were determined by evaluating the granule median diameter, their particle size distribution,
roundness, disintegration time and dissolution rate of SV. Results clearly demonstrated that the
microemulsion-based process was less sensitive tooperating conditions than the water-based process.
With microemulsion the nucleation process and growth regimes were more difficult to control, resulting
in products with broader PSDs. At the same operatingconditions microemulsion-based granules were
more brittle but rounder and showed smaller median diameter compared to water-based granules. The
dissolution rate of simvastatin was not significantly affected by the operating conditions
Preparation and characterization of etoricoxib solid dispersions using lipid carriers by spray drying technique
The basic objectives of this study were to prepare and characterize solid dispersions of poorly water-soluble drug etoricoxib using lipid carriers by spray drying technique. The properties of solid dispersions were studied by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), differential scanning calorimetry (DSC), hotstage microscopy (HSM), radiograph powder diffraction (XRPD), and dissolution studies. The absence of etoricoxib peaks in XRPD profiles of solid dispersions suggests the transformation of crystalline etoricoxib into an amorphous form. In the HSM examination of solid dispersions, the dissolution of drug in the lipid carriers was observed, which was also confirmed by the absence of etoricoxib peak in DSC curves of solid dispersions. The DRIFTS spectra revealed the presence of hydrogen bonding in solid dispersions. The in vitro dissolution rate of solid dispersions as compared with pure etoricoxib, spray-dried etoricoxib, and physical mixtures of drug with lipid carriers. Therefore, the dissolution rate of poorly water-soluble drug etoricoxib can be significantly enhanced by the preparation of solid dispersions using lipid carriers by spray drying technique