Page 62 - Pharmaceutics III_ 02-06-01304_Fall 2025_ Pharm D_Electronic book

Defect Description Cause Remedy
Adjust drying air temp
Cracking Breaks on film Rapid drying Reduce solids content
Lower drying temp
Bridging Film covers embossed Excess viscosity Increase atomization
letters

Blistering Film detaches in blisters Entrapped solvent vapor

Orange Rough surface Spray droplets dry before
peel spreading

Granulation Techniques (Detailed):
Wet Granulation:

• Binder solutions: starch paste, PVP, gelatin, HPMC.
• Granulating solvents: water, ethanol, isopropanol.
• Drying methods: tray drying, fluid-bed drying, microwave drying.
• Moisture endpoint: 1–2 %.
Dry Granulation:
• Roller compactor parameters: roll pressure, gap, speed.
• Slugging pressure: 3–10 tons/in².
Direct Compression:
• Compressibility index (Carr’s Index < 20 %) indicates suitability.
• Flow properties evaluated by angle of repose (< 30°).

Evaluation of Granules:
1. Bulk density: W/V (g/mL).
2. Tapped density: after tapping 100 times.
3. Compressibility index = [(Tapped – Bulk)/Tapped]×100.
4. Hausner ratio = Tapped/Bulk density.
o ≤ 1.25 → good flow.
5. Angle of repose: tan θ = h/r; < 30° = excellent flow.

Tablet Process Optimization:
• Compression force, dwell time, turret speed monitored.

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