Top Granulation Interview Questions and Answers for Pharma Jobs

Getting a job in the pharma industry is extremely competitive. To stand out from other candidates, you need to be fully prepared for the interview, especially if you are interviewing for a production role like in the granulation department In this article, I will provide the top granulation interview questions and answers to help you ace your next pharma interview

The granulation process is a critical step in pharmaceutical manufacturing. It improves the flow and compression properties of powders to make them suitable for tablet and capsule production. Granulation interview questions test your core knowledge of the granulation process, equipment, critical process parameters, and more. Being well-versed in these areas is key to landing your dream pharma job.

Let’s dive into the top granulation interview questions and answers

Q1. What is granulation and why is it important?

Granulation refers to the process of forming granules by agglomerating fine powder particles using a binder solution or dry compaction forces,

It is a critical step in pharmaceutical manufacturing for the following reasons:

• Improves powder flow properties
• Increases compressibility of the powder
• Improves blend uniformity, especially for potent drugs
• Reduces tableting defects like capping and sticking
• Alters particle size distribution to be more uniform

Q2. What are the different types of granulation processes?

The main types of granulation processes are:

• Wet granulation – using a liquid binder
• Dry granulation – using compaction/slugging
• Hot melt granulation – using a molten binder
• Spray drying – dissolving/suspending drug in a solvent and spray drying
• Extrusion/spheronization – extruding moist mass through a die

Q3. How do you determine the end point of granulation?

Common ways to determine optimal end point include:

• Visual observation – granules should be uniform in size/color
• Hand squeeze test – granules should form aggregates that break into 2-3 pieces
• Power consumption of the mixer motor
• Impeller torque
• Granule size distribution analysis

The end point ensures suitable granule properties for the next manufacturing steps.

Q4. Explain the working principle of a Rapid Mixer Granulator (RMG).

A RMG works on the principle of agitation and tumbling. The impeller uniformly mixes the binder solution and powder. The chopper helps break any oversized aggregates.

Q5. What are the critical process parameters during granulation?

Critical process parameters include:

• Binder preparation time and mixing speed
• Amount of binder solution
• Dry/wet mixing time
• Impeller and chopper speed
• Ampere load

Controlling these are crucial to achieve the desired granule properties.

Q6. What are the critical granule attributes and how are they tested?

Critical quality attributes are:

• Particle size distribution – tested by sieve analysis
• Flow properties – angle of repose, Carr’s index
• Moisture content – loss on drying test
• Bulk/tapped density – bulk density apparatus
• Blend uniformity – content uniformity testing

Meeting specifications for these attributes ensures suitability for downstream processing.

Q7. Name some common equipment used in wet granulation.

• High shear wet granulator
• Fluid bed dryer
• Vibro sifter
• Multi mill, hammer mill, comil (size reduction)
• Rapid mixer granulator (binding/agglomeration)
• Extruder and spheronizer (size enlargement)

Familiarity with these equipments is expected in granulation interview questions.

Q8. What are the typical sieve standards used for granulation?

Typical sieve sizes (US mesh) are:

• 10, 20, 40, 60, 80, 100, 200

Corresponding sieve aperture sizes range from 2000 μm to 74 μm. Knowledge of mesh sizes is important for analyzing granule size distribution.

Q9. What is the working principle of a vibro sifter?

Vibro sifters use gyratory vibrations to segregate particles based on size. Oscillations are generated by a specially designed gyro motor. This facilitates screening of particles into different size fractions.

Q10. How can you minimize static charge generation in a vibro sifter?

Methods to minimize static charge generation include:

• Using anti-static screens
• Earthing the assembly by attaching a C-clamp on silicone screens
• Proper exhaust ventilation

Control of static is critical for operator safety and to avoid segregation issues.

Q11. What are the critical process parameters during fluid bed drying?

Critical process parameters for fluid bed drying include:

• Inlet/outlet air temperature
• Airflow rate
• Dew point
• Drying time

Controlling these parameters is vital to achieve the target moisture content and desired granule properties.

Q12. What are the main parts of a fluid bed dryer?

Key components of a fluid bed dryer are:

• Plenum chamber
• Product container
• Expansion chamber
• Exhaust blower
• Finger bag assembly with bag shaker
• Air handling units for heating/dehumidifying
• Spraying system (for top spray)
• Process sensors – pressure, temperature, humidity

Thorough knowledge of fluid bed parts is expected in the interview.

Q13. What are the typical sieve sizes used for lubrication blends?

Common sieve sizes are:

• 16, 30, 44, 60, 85, 120, 200

These are selected based on the desired tablet properties and performance. Proper sieving improves blend uniformity.

Q14. How do you determine the end point of the lubrication blend?

The lubrication end point is typically determined based on:

• Specified blending time
• Analysis of blend uniformity – should meet acceptance criteria
• No further improvement in blend uniformity with increased blending time

This ensures adequate distribution of the lubricant for successful tablet manufacturing.

Q15. What are the critical quality attributes for the lubricated blend?

Critical lubricated blend attributes are:

• Blend uniformity – assay, content uniformity
• Particle size distribution
• Powder flow properties
• Moisture content

Meeting specifications for these is necessary for proper capsule filling or tablet compression.

Q16. What are the different types of lubricants used in tablet manufacturing?

Commonly used lubricants include:

• Magnesium stearate
• Stearic acid
• Sodium stearyl fumarate
• Calcium stearate
• Hydrogenated vegetable oil
• Polyethylene glycol

Being familiar with different lubricant options shows your well-rounded knowledge.

Q17. How do you calibrate the moisture balance for testing?

Calibration is done using standard reference material like anhydrous sodium tartrate:

• Measure 2g sample in moisture analyzer pan
• Run test and check %moisture is 15-16%

This verifies proper functioning of the moisture balance.

Q18. What are the hazards associated with the granulation process?

Some potential hazards are:

• Dust explosion risk from fine powders
• Noise hazards from equipment like mills and sifters
• Ergonomic injuries from repetitive tasks, lifting
• Static charge generation during sieving

Having knowledge of hazards shows you take safety seriously.

Q19. How can you make the granulation process more efficient?

Some ways to improve efficiency:

• Optimize binder solution preparation
• Use appropriate sized equipment
• Automate material handling steps
• Schedule preventive maintenance of equipment
• Continuously monitor critical process parameters
• Leverage data analytics for process optimization

This demonstrates you have a mindset for continuous improvement.

Q20. Why is blend uniformity testing important?

Blend uniformity ensures:

• Uniform distribution of drug/excipients
• Consistent dose in each tablet
• Improved product quality and reproducibility

Testing blend uniformity is a critical in-process control to ensure final product quality.