RESUMEN
Spray drying is a well-established method for screening spray dried dispersions (SDDs) but is material consuming, and the amorphous solid dispersions (ASDs) formed have low bulk density. Vacuum Compression Molding (VCM) is a potential method to avoid these limitations. This study focuses on VCM to screen ASDs containing itraconazole and L, M, or H polymer grades of hydroxypropyl methylcellulose acetate succinate (HPMCAS) and compares their morphology, amorphous stability, and dissolution performance with spray drying. Results indicate that VCM ASDs were comparable to SDDs. Both VCM ASDs and spray drying SDDs with HPMCAS-L and HPMCAS-M had improved dissolution profiles, while HPMCAS-H did not. Dynamic light scattering findings agreed with dissolution profiles, indicating that L and M grades produced monodisperse, smaller colloids, whereas H grade formed larger, polydisperse colloids. Capsules containing ASDs from VCM disintegrated and dissolved in the media; however, SDD capsules formed agglomerates and failed to disintegrate completely. Findings indicate that the VCM ASDs are comparable to SDDs in terms of dissolution performance and amorphous stability. VCM may be utilized in early ASD formulation development to select drug-polymer pairs for subsequent development.
Asunto(s)
Dapsona/análogos & derivados , Itraconazol , Secado por Pulverización , Vacio , Solubilidad , Polímeros , Coloides , Metilcelulosa , Composición de MedicamentosRESUMEN
Proper screw design is crucial for effectively pre-treating wood fibers, to assist in the downstream enzymatic conversion of the cellulose into fermentable sugars. Initially, the impact of extruder barrel temperature (50, 100, and 150⯰C) and screw speed (25, 50, and 75â¯rpm) were studied to arrive at the optimum conditions for sugar yield. Lower temperatures and screw speeds resulted in increased sugar yields. To examine the influence of shear imparted by the screws, the residuals samples were recovered from different zones along the screws and evaluated. Sugar yield, crystallinity index, and the particle size distribution of the material collected at different zones were determined. Glucose yield and xylose/mannose yields of the material along the screws, ranged from 23.25 to 42.88% and from 11.95 to 20.54%, respectively. The importance of the screw design was highlighted.
Asunto(s)
Biomasa , Celulosa/metabolismo , Fermentación , Glucosa/biosíntesis , Elastómeros de Silicona , Azúcares/metabolismo , TemperaturaRESUMEN
Extrusion of 2 quinoa varieties, Cherry Vanilla and Black (scarified and unscarified) and a mixed quinoa variety, Bolivian Royal (scarified and degermed) were studied for their extrusion characteristics. A corotating twin-screw extruder with a 3 mm round die was used. Feed moisture contents of 15%, 20%, and 25% (wet basis) were studied. The extruder barrel temperature was kept constant at 140 °C and screw speeds were varied from 100, 150, and 200 revolutions per minutes. Process responses (specific mechanical energy, back pressure, and torque) and product responses (expansion ratio, unit density, and water absorption index/water solubility index) were evaluated. The degermed Bolivian Royal showed the highest expansion in comparison to all other varieties, attributed to its significantly low levels of fat, fiber, and protein. The scarified Cherry Vanilla resulted in the lowest expansion ratio. This was attributed to the increase in the protein content from the removal of the outer layer. The results indicate that all the varieties performed differently in the extrusion process due to their modification processes as well as the individual variety characteristics.