Modelling phase separation in amorphous solid dispersions

Amorphous-Amorphous Phase Separation in API/Polymer Formulations.

The long-term stability of pharmaceutical formulations of poorly-soluble drugs in polymers determines their bioavailability and therapeutic applicability. However, these formulations do not only often tend to crystallize during storage, but also tend to undergo unwanted amorphous-amorphous phase separations (APS). Whereas the crystallization behavior of APIs in polymers has been measured and mo...

Phase Separation in Bimodal Dispersions of Sterically Stabilized Silica Particles

Binary mixtures of suspended, nearly hard-sphere, sterically stabilized colloidal silica particles of diameter ratio 6 were observed to phase-separate at comparable volume fractions of the two particle species. The occurrence of phase separation as a function of the particle concentrations was studied visually and by small-angle light scattering. The results support recent predictions by Biben ...

Self-crowding induced phase separation in protein dispersions.

The coupling between protein conformation, molecular volume, and solution phase behaviour is studied theoretically for a two-state, coarse-grained protein model in which protein molecules can reversibly switch between a native and a non-native excited state. In the model, native and non-native conformers are represented by perfect spheres with different hard-core diameters. We presume the large...

Characterization of Olanzapine – Solid dispersions.

Aim: To enhance the aqueous solubility of olanzapine by using the Solid dispersion technique. Solid dispersions of Olanzapine were prepared by the dispersion method using using PGS and SSG as carriers. Drug:carrier ratios such as 1:1, 1:2, 1:4, 1:6, 1:8 and 1:10 were tried for optimization. Characterization was done by phase solubility, in vitro release, saturation solubility, permeation, wetta...

Limitations in the Pharmacopeial Dissolution Testing of Marketed Tacrolimus Amorphous Solid Dispersions