Page 69 - Pharmaceutics III_ 02-06-01304_Fall 2025_ Pharm D_Electronic book
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3. Tapped density (ρt): W/Vt after tapping.
4. Carr’s index: [(ρt–ρb)/ρt]×100; <15 = good.
5. Hausner ratio: ρt/ρb; <1.25 = good flow.
Flow Improvement Techniques:
• Granulation.
• Use of glidants (talc, colloidal silica).
• Particle size control.
• Moisture adjustment.
Disintegration Mechanisms (Detailed):
1. Swelling:
o Disintegrant swells upon hydration, rupturing tablet.
o Example: sodium starch glycolate.
2. Wicking (capillary action):
o Water drawn into pores, reduces particle cohesion.
o Example: crospovidone.
3. Gas generation:
o Effervescent systems release CO₂.
4. Enzymatic action:
o Rarely used (starch degradation by amylase).
Factors Affecting Disintegration:
• Amount and type of binder (excess retards disintegration).
• Lubricant concentration (hydrophobic films).
• Compression force (hard tablets disintegrate slowly).
• Moisture content.
Dissolution Testing (Advanced):
Purpose: to assess bioavailability correlation (IVIVC).
Apparatus:
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