Page 54 - Practical Technology 2025
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Clinical Pharmacy-Pharm D Level Three 2 Semester 2024/2025 Pharmaceutical Technology (PT 607)
Lab (6): Tablets Hardness and Friability Tests
I) Tablet hardness:
Tablet hardness or sometimes termed as (Tablets Crushing Strength) is defined as the force
required to break a tablet in a diametral compression test.
A tablet requires a certain amount of strength or hardness to withstand mechanical shocks of
handling in its manufacturing, packaging, and shipping.
The hardness is an important test as it influences disintegration of tablet and subsequently,
the drug dissolution rate.
Apparatus: Erweka hardness tester
• The tablet is placed between two anvils.
• Pressure is applied to the anvils, and the crushing strength that causes
the tablet to break is recorded.
Factors Affect Tablet Hardness:
1. Hardness is a function of applied pressure. As additional pressure is applied to make a
tablet, the hardness values increase, this relationship holds up the maximum value
beyond which increases in pressure cause the tablet to laminate or cap, thus destroying
the integrity of the tablet.
2. Tablets which contain ingredients with moisture are generally harder several hours after
compression than they are immediately compressed.
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