The document discusses 11 different techniques to determine granulation end point in pharmaceutical manufacturing processes. Visual observation is the conventional but subjective method, while techniques like power consumption, impeller torque, conductivity, and acoustic emission aim to provide more objective and reproducible measurements of changes in granule properties online. Additional offline methods like rheometry, effusivity, and spectroscopy also characterize granulation but can be more expensive.

1. Different Techniques to
determine Granulation end point
1. Visual observation
- Conventional method
- Skill based
- May vary from person to person
- May vary for same person form time to
time
- Subjective (Reproducibility)

2. 3. Impeller Torque
- Online
- Changes in torque on the blades measured
- More sensitive than power consumption
technique
- Subjective
2. Power consumption
- Inexpensive and online
-Change in current load is measured.
- Change in current load is due to change in
cohesive force or amount of resistance impeller
experience to keep certain rotational force
- Subjective

3. 4. Conductivity
- Measures uniformity of liquid distribution in
damp mass
- Change in Packing density of particles
- Not extensively used
5. Probe vibration
- Measures increase in granule size
- Increase in granule size increases the
acceleration of agglomerates

4. 6. Boots Diosna probe
- Measures densification and increase in size
of granules
- Densification changes the momentum of
granules moving
- Not used due to invasive nature
7. Capacitance sensor
- Measures Moisture distribution and granule
formation
- Subjective

5. 8. Torque rheometer
- Offline technique
- Measures rheological properties of the
granulation
9. Acoustic Emission
- Online technique
- Measures ultrasonic sound (Acoustic emission)
generated by movement of particles
- Non invasive
- Reproducible
- Accurate

6. 10. Effusivity
- Measures effusivity of different particle
under mixing. (Effusivity is combination of
Thermal conductivity, Density and heat
capacity)
- Sensitive
- Offline
11. Other methods
- Spectroscopic methods like NIR, Raman
spectroscopy methods etc.
- Expensive

7. 10. Effusivity
- Measures effusivity of different particle
under mixing. (Effusivity is combination of
Thermal conductivity, Density and heat
capacity)
- Sensitive
- Offline
11. Other methods
- Spectroscopic methods like NIR, Raman
spectroscopy methods etc.
- Expensive