13. September 2018
Orodispersible films (ODFs) provide high application comfort due to rapid disintegration in the oral cavity. They increasingly found the approval of pharmaceutical research and development and were added to the European Pharmacopeia in 2012. The European Pharmacopeia explicitly demands disintegration testing for ODFs, but does not refer to a suitable method. The aim of this study was to collect and evaluate existing disintegration methods regarding their suitability to investigate different ODF...
16. September 2017
Abstract We aimed to understand the factors controlling mechanical particle coating using polymethacrylate. The relationship between coating performance and the characteristics of polymethacrylate powders was investigated. First, theophylline crystals were treated using a mechanical powder processor to obtain theophylline spheres (<100 μm). Second, five polymethacrylate latexes were powdered by spray freeze drying to produce colloidal agglomerates. Finally, mechanical particle coating was...
20. April 2017
Abstract The purpose of this study is to demonstrate that the flow function (FFc) of pharmaceutical powders, as measured by rotational shear cell, is predominantly governed by cohesion, but not friction coefficients. Driven by an earlier report showing an inverse correlation between FFc and the cohesion divided by the corresponding pre-consolidation stress [Wang et al. 2016. Powder Tech. 294:105-112], we performed analysis on a large dataset containing 1130 measurements from a ring shear...
11. April 2017
Abstract Ribavirin (C8H12N4O5; anti-viral agent) was crystallized as two unique, phase-pure polymorphs (R-I and R-II). Calorimetrically determined isobaric heat capacities and heat of transition data were utilized to determine the solid-state transition temperature (Ttr), confirming enantiotropism, while R-I was determined to be kinetically stable at ambient temperature. Unprocessed samples of the low Tm polymorph, R-II, did not convert into R-I when held isothermally well above Ttr for 7 days....
03. April 2017
Abstract Capping or lamination is an unsolved common problem in tablet manufacturing. Knowledge gaps remain despite an enormous amount of effort made in the past to better understand the tablet capping/lamination phenomenon. Using acetaminophen – containing formulations, we examined the potential use of a compaction simulator as a material-sparing tool to predict capping occurrence under commercial tableting conditions. Systematical analyses of the in-die compaction data led to insight on the...
15. March 2017
Abstract The formulation of lipophilic and hydrophobic compounds is a challenge for the pharmaceutical industry and it requires the development of complex formulations. Our first aim was to investigate hot-melt extrudate microstructures by means of multifractal analysis using scanning electron microscopy imaging. Since the microstructure can affect solid dosage form performance such as mechanical properties, a second objective was to study the influence of the type of adsorbent and of the...
12. March 2017
Abstract Novel excipients are entering the market to enhance the bioavailability of drug particles by having a high porosity and thus providing a rapid liquid uptake and disintegration to accelerate subsequent drug dissolution. One example of such a novel excipient is functionalised calcium carbonate (FCC), which enables the manufacture of compacts with a bimodal pore size distribution consisting of larger inter-particle and fine intra-particle pores. Five sets of FCC tablets with a target...
08. November 2016
Abstract The objective was to investigate poly vinyl acetate (Kollicoat® SR 30 D) and ammonio methacrylate copolymer (Eudragit® RL 30 D) blends as coatings to increase the mechanical robustness of hydroxypropyl methylcellulose (HPMC) matrix tablets. Poly vinyl acetate (Kollicoat® SR 30 D – KSR) was selected for its flexibility and ammonio methacrylate copolymer (Eudragit® RL 30 D – ERL) because of its high permeability. Films based on KSR:ERL blends were prepared by casting or spraying...
27. October 2016
Abstract Multiple unit pellet system(s), MUPS, is one of the most commonly used means for achieving modified drug release through oral administration. MUPS is usually delivered as capsules that contain drug bearing beads coated with a release modulating functional layer. While the routine manufacture of tablets of MUPS by direct compression is highly desired, it is faced with the problem of poor tableting properties or altered drug release behavior due to the rupture of the functional coating...
01. October 2016
Abstract Flashing at tablet edges, an inevitable phenomenon when tableting a plastically deforming material under a high pressure, can introduce significant errors to tablet density and porosity determinations due to overestimated tablet thickness when tablet were measured out-of-die. Errors in tablet density determination also lead to errors in true density obtained by the Sun method, which is suitable for water-containing solids. Errors in true density and tablet porosity propagate to...