Date of Award
M.S. in Pharmaceutical Science
Pharmaceutics and Drug Delivery
Michael A. Repka
S. Narasimha Murthy
Samir A. Ross
The objective of the current study was to investigate the processability of Aquasolve™ HPMC-AS LG via hot-melt extrusion, and to examine the effect of pressurized carbon dioxide (P-CO2) on the physico-mechanical properties of Efavirenz (EFA)-loaded extrudates (EXT). EFA is as a poorly water-soluble drug and HPMC-AS LG was chosen as a carrier for this study. To optimize the process parameters and formulations, various physical mixtures were prepared with the following composition: EFA (30-40-50% w/w) and HPMC-AS LG (70-60-50 % w/w) respectively. Physical mixtures were extruded through the co-rotating twin-screw extruder (16mm Prism Euro Lab, Thermo Fisher Scientific) utilizing a standard screw configuration. P-CO 2 was injected into eight zone of extruder using a high-pressure regulator connected to flexible stainless-steel hose with armor casing. The thermal characterization of extrudates was obtained by using differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). A scanning electron microscopy (SEM) was conducted to study morphology and porosity of formulations. The macroscopic morphology changed to a foam-like structure, resulting in increased specific surface area, porosity and dissolution rate. Thus, HPMC-AS LG extrudates with P-CO2 injection exhibited relatively higher dissolution rate than extrudates without P-CO2. Additionally, HPMC-AS LG was able to physically and chemically stabilize the amorphous state of high-loading EFA in the extrudates. The milling efficiency was improved for extrudates with P-CO2 injection due to porous nature and morphology changes.
Almutairi, Mashan, "Feasibility of AquasolveTM HPMC-AS Lg via Hot-melt Extrusion: Effect of Pressurized CO2 on Physico-mechanical Properties" (2018). Electronic Theses and Dissertations. 1338.