Pelletization Flashcards
What are the characteristics of pellets?
- Particle size; porosity, volume, density
- Define diameter
- Spherical shape; flow
What are the roles of pellets?
- MR
- Intermediate for dosage forms - tabs, caps, suspensions
- Dosage form unit
- Separation pf incompatible drugs
What are the methods to produce pellets?
- Layering from liquids - heterogeneous
- Layering from powders - heter
- Melt granulation pelletization - homo
- Wet granulation pelletization - homo
Explain layering from liquid
Start with a core, then add liquid binder and wait for it to harden from pellets - can add multiple layers.
Explain layering from powder
Same as liquid - the liquid binder is added to core and the fine powder is added until they cover the core and are evenly distributed - a layer is formed and the process is repeated until many layers formed.
What are the core materials?
Sugars: sucrose, maize starch, excipients, drug crystals, microcrystalline cellulose spheres
Explain wet granulation pelletization
Wet granulation is the powder + liquid binder + energy, mixed into a wet mass and then you put them into the pellet shape - NO CORE
What is melt granulation pelletization?
Drug powder + powder binder are mixed. The mixing and head causes binder powder to melt and make mass. The pellets are discharged and cooled.
Describe extrusion and spheronisation
- Mix solid + liquid to make wet mass
- Shaping and densification
- Subdivison
- Shaping
- Pellet formed
- Drying
What are the parameters affecting quality of extrudates?
Plasticity
Length/ diameter
Self-lubricating
Rigidity
Rate of wet mass feeding
Fluidity
Formulation components
What is the shaping process during shperonisation?
Cylinders are inserted into apparatus and it is rotated quickly, hitting each other and the sides of the chamber, the cylinders will become more rounded and eventually become pellets.
1. Cylinders
2. Rounded ends
3. Dumb-bells
4. Spheres/ pellets
