Novel platens to measure the hardness of a pentagonal shaped tablet.

Tablet hardness, a measure of the breaking force of a tablet, is based on numerous factors. These include the shape of the tablet and the mode of the application of force. For instance, when a pentagonal-shaped tablet was tested with a traditional hardness tester with flat platens, there was a large variation in hardness measurements. This was due to the propensity of vertices of the tablet to crush, referred to as an "improper break". This article describes a novel approach to measure the hardness of pentagonal-shaped tablets using modified platens. The modified platens have more uniform loading than flat platens. This is because they reduce loading on the vertex of the pentagon and apply forces on tablet edges to generate reproducible tablet fracture. The robustness of modified platens was assessed using a series of studies, which included feasibility and Gauge Repeatability & Reproducibility (R&R) studies. A key finding was that improper breaks, generated frequently with a traditional hardness tester using flat platens, were eliminated. The Gauge R&R study revealed that the tablets tested with novel platens generated consistent values in hardness measurements, independent of batch, hardness level, and day of testing, operator and tablet dosage strength.

Mechanistic insights into the scale-up of the roller compaction process: a practical and dimensionless approach.

Although the roller compaction process appears simple, efforts to quantitatively model the process have proven challenging because of complex material behavior in the feeding and compaction zones. To date, implementation of roller compaction models to experimental work has been limited because these models typically require large experimental data sets or obscure input parameters that are difficult to obtain experimentally. In this work, an alternative approach has been established, expanding upon a widely used roller compaction model, Johanson's model, to enable its incorporation into a daily workflow. The proposed method requires only standard, routinely measured parameters as inputs. An excellent correlation between simulated and experimental results has been achieved for placebo and active blends up to 22% (w/w) drug load. Furthermore, a dimensionless relationship between key process parameters and final compact properties was elucidated. This dimensionless parameter, referred to as the modified Bingham number (Bm *), highlights the importance of balancing yield and viscous stresses during roller compaction to achieve optimal output properties. By maintaining a constant ratio of yield-to-viscous stresses, as indicated by a constant Bm *, consistent products were attained between two scales of operation. Bm * was shown to provide guidance toward determining the design space for formulation development, as well as to facilitate scale-up development.