Monitoring lubricant addition in pharmaceutical tablet manufacturing through passive vibration measurements in a V-blender

In tablet manufacturing, a lubricant is added in a tumbling mixer prior to compression to ensure that the tablet is ejected smoothly without sticking or breakage. Control and monitoring of this process is critical as process parameters can negatively affect final tablet properties. Inline monitoring methods including passive vibration measurements could be implemented to improve process efficiency. This method is non-invasive, non-destructive, and has a reduced cost compared to other monitoring techniques. Using an accelerometer affixed to the lid of a V-blender, magnesium stearate was added to glass beads and granule formulations and monitored to determine the effect of lubricant concentration, particle size, and particle size distribution on vibration measurements. Mixing end-points were identified and changes in mixing profiles were reflected in signal amplitude and variation. This research indicates that passive vibration measurements have the potential to be used as a real-time inline monitoring method for lubricant addition. [Display omitted] •Measured vibrations from particle collisions provide information about the particle.•Lubricant forms a layer around the particles thereby altering energy dissipation upon impact.•Particle surface morphology alter the development of the lubricant layer.•The mixing end-point of lubricant dispersal can be identified through measured vibrations.•Mixing profiles were affected by particle size and size distribution, surface morphology and amount of lubricant.