Posts tagged with "Solid-state"



19. April 2017
Abstract We developed a step-by-step experimental protocol using differential scanning calorimetry (DSC), dynamic vapour sorption (DVS), polarized light microscopy (PLM) and a small-scale dissolution apparatus (μDISS Profiler) to investigate the mechanism (solid-to-solid or solution-mediated) by which crystallization of amorphous drugs occurs upon dissolution. This protocol then guided how to stabilize the amorphous formulation. Indapamide, metolazone, glibenclamide and glipizide were selected...
07. April 2017
Abstract A compound, which is a selective peroxisome proliferator activated receptor (PPAR) agonist, was investigated. The aim of the presented studies was to evaluate the potential of the further development of the compound. Fundamental physicochemical properties and stability of the compound were characterized in solution by liquid chromatography and NMR and in solid-state by various techniques. The drug itself is a poorly soluble lipophilic acid with tendency to form aggregates in solution....
10. January 2017
Abstract The purpose of this study was to determine the drug-polymer miscibility of GENE-A, a Genentech molecule, and Hydroxypropyl methylcellulose-acetate succinate (HPMC-AS), a polymer, using computational and experimental approaches. The Flory-Huggins interaction parameter,χ, was obtained by calculating the solubility parameters for GENE-A and HPMC-AS over the temperature range of 25–100 °C to obtain the free energy of mixing at different drug loadings (0-100%) using the Materials Studio...
11. October 2016
Abstract One of the main obstacles to the successful treatment of tuberculosis is the poor and variable oral bioavailability of rifampicin (RIF), which is mainly due to its low hydrophilicity and dissolution rate. The aim of this work was to obtain a hydrophilic new material that allows a very fast dissolution rate of RIF and therefore is potentially useful in the development of oral solid dosage forms. The acid form of carboxymethylcellulose (CMC) was co-processed with RIF by solvent...
15. August 2016
Abstract The saturation solubility of PVP:PZQ physical mixtures (PMs) and solid dispersions (SDs) prepared from ethanol (E/E) or ethanol/water (E/W) by the solvent evaporation method at 1:1, 2:1 and 3:1 ratio (w/w) was determined. The presence of PVP improves the solubility of PZQ (0.31 ± 0.01 mg/mL). A maximum of 1.29 ± 0.03 mg/mL of PZQ in solution was achieved for the 3:1 SD (E/E). The amount of PZQ in solution depends on the amount of polymer and on the preparation method. Solid-state NMR...
20. June 2016
Abstract The possibility of producing amorphous isomalt and melibiose by spray drying was studied. The impact of process parameters on yield and solid-state stability was compared to sucrose and trehalose. All powders remained amorphous during 2–3 weeks. Processing was challenging due to powder stickiness. Low-temperature and low-humidity drying processes generally performed best. Most isomalt and sucrose powder was retrieved when using 60 °C inlet temperature, 800 L/h atomizing rate, 1.4...
22. January 2016
Excipients used in the solid drug formulations differ in their NMR relaxation and 13C cross-polarization (CP) kinetics parameters.Therefore, experimental parameters like contact time of crosspolarizationand repetition time have a major impact on the registeredsolid state NMR spectra and in consequence on the results of the NMRanalysis. In this work the CP kinetics and relaxation of the most common pharmaceutical excipients: anhydrous α-lactose, α-lactose monohydrate, mannitol, sucrose,...
17. December 2015
Understanding the impact of pharmaceutical processing, formulation excipients and their interactions on the solid-state transitions of pharmaceutical solids during use and in storage is critical in ensuring consistent product performance. This study reports the effect of polymer viscosity, diluent type, granulation and granulating fluid (water and isopropanol) on the pseudopolymorphic transition of theophylline anhydrous (THA) in controlled release formulations as well as the implications of...
22. September 2015
Praziquantel (PZQ), an anthelmintic drug used in developing countries for the treatment of schistosome infections, was processed using the fluid bed wet granulation technology to prepare fast dispersible granules, as an appropriate and flexible dosage form for pre-school-aged children. More