By Brian C. Anderson
Granulation has been employed within the pharmaceutical industry for decades. An essential manufacturing process which is used to form aggregated granules from a powder, it enhances the properties of a drug through material densification and is widely used as an intermediate process within solid dosage manufacturing.
Typically performed once powders containing the active pharmaceutical ingredient (API) and any excipients have been mixed together to a defined ratio, granulation affords many advantages. By modifying the uniformity of API distribution, it decreases segregation of ingredients to generate a consistent product. It can also improve compressibility and flow properties of powders while reducing dust to minimize losses and handling hazards.
Various granulation techniques have been developed. Dry methods involve the use of applied pressure to compact powdered material, while wet granulation requires the introduction of a specialized binder to cause aggregate formation. Melt granulation relies on a meltable binding agent that amalgamates with the powder upon heating.
Understanding and being able to control granulation is essential to the production of high quality pharmaceuticals. Affording superior process reproducibility and better process control than many other granulation techniques, fluid bed granulation and melt granulation can be tightly regulated to produce uniform material with a specified particle size.