In the Pharmaceutical industry, Granulation can be defined as the act or process in which primary powder particles are adhered to form larger, multi-particle entities.
Typically during the production of tablets and capsules, granules are made as an intermediate product and have a usual size range between 0.2 to 0.5 mm, while larger granules are used as a dosage form.
Granulation particularly starts after initial dry mixing of the required powdered ingredients so that there is a consistent distribution of each ingredient through the mix.
But!!!! Why Particularly Only Me?
There are various reasons for choosing the granulation method out of the various tablets manufacturing process.
- To avoid segregation of the components of the powder mix:
Please, don’t blend me with them!!!
Segregation also called de-mixing is done because of the differences in the size of the components of the mix. The smaller particles are usually at the base of a container while the large particles are above it.
To have a perfect granulation, all the constituents of the mix should be in exact proportion in every granule and then de-mixing of the ingredients will not occur. It is even vital to control the particle size distribution of the granules as the individual components might not segregate themselves and if by chance there is a wide size distribution, the granules may get segregated by themselves.
- In order to improve the flow properties of the powder mix:
Oh my god, I’m so uneven!!!
Numerous powders for reasons such as small size, irregular shape and surface characters are cohesive and thus do not flow well. Poor flow results in a huge weight variation in the final product due to uneven fill of tablet dies, etc.
As a result, the granules become larger and more diametric created from such a cohesive system.
- Occupies very less place
O.M.G! I’m so flexible!!!
Granules are usually take up less volume per unit weight and are denser than the powder mix. Therefore, they’re more convenient for storage and shipment purpose.
For heaven sake, I’ve even got types!!!
There are even some different kinds of granulation in the pharmaceutical industry. They are as follows:
- Wet Granulation
- Dry Granulation
- Steam Granulation
- Foam Granulation
- Wet Granulation:
Therefore, I’m so renowned!!!
Wet Granulation is the most renowned method for tablet production as it can be applied to about any dosage of any drug. The wet granulation of powders enhances the flow and compatibility of the compression mix and because of this it is very popular.
Some of its advantages include:
- It allows mechanical handling of powders without any loss of quality of blend.
- It increases & improves the consistency of powder density and hydrophobic surfaces are made hydrophilic.
- It lessens the level of dust and cross-contamination and the air entrapment is reduced.
- It improves cohesion during and after compaction and permits for the addition of a liquid phase to powders.
- Dry Granulation:
Ha, I’m so reasonable
Dry Granulation in the Pharmaceutical industry is used for forming granules without the usage of a liquid solution because the product granulated can be sensitive to moisture and heat. Forming granules without moisture needs compacting and densifying the powders.
Some of the advantages of this kind of granulation include:
- It is a very simple and low-cost method, and is the reason of it being renowned.
- It assists in increasing the size of granules within powders, making it much easier to shape them into tablets or capsules. It even leads to dense and stable formulations for the use in filling capsules.
- Steam Granulation:
Oh la la, It’s so Steamy!!!
Granulation is the modification of wet granulation where steam is used as a binder instead of water.
Some of its advantages include:
- It has higher distribution uniformity and diffusion rate into powders
- It is the most favored thermal balance during drying step and the steam granules are even more spherical.
- They’ve large surface area. Therefore, there is increased dissolution rate of the drug from granules.
- The processing time is shorter which means there are more number of tablets produced per batch.
- Foam Granulation:
Yee Aqua Aqua!!!
The liquid binders in this type of granulation are added as aqueous foam.
Some of its advantages include:
- This requires less water when compared to the wet granulate.
- The rate of addition of foam is greater when compared to the rate of addition of sprayed liquids.
