High-Molecular-Weight Hypromellose from Three Different Suppliers: Effects of Compression Speed, Tableting Equipment, and Moisture on the Compaction

Dwell time on tableting: dwell time according to force versus geometric dwell time

Dwell time is an important parameter responsible for the material deformation and the mechanical and biopharmaceutical properties of the tablet. Thus, it is widely used for scale-up purposes. The geometric dwell time (GDT) can be assumed based on the shape of the punch head and the diameter and speed of the turret. This research is aimed to compare compaction simulator-recorded dwell time according to force (DTF) and the GDT calculated for the simulated rotary tablet press using the microcrystalline cellulose and calcium phosphate mixtures (CEOLUS™ UF-711 and DI-CAFOS® A60) in different proportions. Tablets were prepared, and DTF was analyzed with a compaction simulator (STYL'One Nano and Alix software) upon simulating a small rotary press at 70 rpm and a compression pressure of 10-50 kN (100-500 MPa). While GDT comprised of 14.4 ms, DTF was compression force and formulation dependent. The differences between the DTF values of the formulations decreased as the compression force increased, which was most pronounced at compression forces of 10 and 15 kN.

Mannitol-coated hydroxypropyl methylcellulose as an alternative directly compressible controlled release excipient

One of the most common forms of controlled release technology for oral drug delivery comprises an active ingredient dispersed in a hydrophilic matrix forming polymer such as hydroxypropyl methylcellulose (HPMC), which is tableted via direct compression. However, HPMC may pose problems in direct compression due to its poor flowability. Hence, mannitol syrup was spray-coated over fluidized HPMC particles to produce co-processed HPMC-mannitol at ratios of 20:80, 50:50, and 70:30. Particles of pure HPMC, co-processed HPMC-mannitol, and their respective physical mixtures were evaluated for powder flowability, compression profiles, and controlled release performance. It was found that co-processed HPMC-mannitol consisted of particles with improved flow compared to pure HPMC particles. Sufficiently strong tablets of >2 MPa could be produced at moderate to high compression forces of 150-200 MPa. The dissolution profile could be tuned to obtain desired release profiles by altering HPMC-mannitol ratios. Co-processed HPMC-mannitol offers an interesting addition to the formulator's toolbox in the design of controlled release formulations for direct compression.

Leveraging a multivariate approach towards enhanced development of direct compression extended release tablets

Extended release formulations play a crucial role in the pharmaceutical industry by maintaining steady plasma levels, reducing side effects, and improving therapeutic efficiency and compliance. One commonly used method to develop extended release formulations is direct compression, which offers several advantages, such as simplicity, time savings, and cost-effectiveness. However, successful direct compression-based extended release formulations require careful assessment and an understanding of the excipients' attributes. The scope of this work is the characterization of the compaction behavior of some matrix-forming agents and diluents for the development of extended release tablets. Fifteen excipients commonly used in extended release formulations were evaluated for physical, compaction and tablet properties. Powder properties (e.g., particle size, flow properties, bulk density) were evaluated and linked to the tablet's mechanical properties in a fully integrated approach, and data were analyzed by constructing a principal component analysis (PCA). Significant variability was observed among the various excipients. The present work successfully demonstrates the applicability of PCA as an effective tool for comparative analysis, pattern and clustering recognition and correlations between excipients and their properties, facilitating the development and manufacturing of direct compressible extended release formulations.

Comparative Evaluation of the Powder and Tableting Properties of Regular and Direct Compression Hypromellose from Different Vendors

Hypromellose, a widely used polymer in the pharmaceutical industry, is available in several grades, depending on the percentage of substitution of the methoxyl and hydroxypropyl groups and molecular weight, and in various functional forms (e.g., suitable for direct compression tableting). These differences can affect their physicomechanical properties, and so this study aims to characterise the particle size and mechanical properties of HPMC K100M polymer grades from four different vendors. Eight polymers (CR and DC grades) were analysed using scanning electron microscopy (SEM) and light microscopy automated image analysis particle characterisation to examine the powder's particle morphology and particle size distribution. Bulk density, tapped density, and true density of the materials were also analysed. Flow was determined using a shear cell tester. Flat-faced polymer compacts were made at five different compression forces and the mechanical properties of the compacts were evaluated to give an indication of the powder's capacity to form a tablet with desirable strength under specific pressures. The results indicated that the CR grades of the polymers displayed a smaller particle size and better mechanical properties compared to the DC grade HPMC K100M polymers. The DC grades, however, had better flow properties than their CR counterparts. The results also suggested some similarities and differences between some of the polymers from the different vendors despite the similarity in substitution level, reminding the user that care and consideration should be given when substitution is required.