Punch geometry and formulation considerations in reducing tablet friability and their effect on in vitro dissolution

Area of Science:

• Pharmaceutical Sciences
• Materials Science

Background:

• Tablet friability is a critical quality attribute affecting drug product performance and handling.
• Formulation excipients and manufacturing processes, such as tablet compression, influence tablet mechanical properties.

Purpose of the Study:

• To investigate the impact of formulation variations and tablet compression parameters on tablet friability.
• To identify strategies for reducing tablet friability without compromising drug dissolution.

Main Methods:

• Tablets were formulated with varying excipients (lactose, microcrystalline cellulose, magnesium stearate, stearic acid).
• Tablet friability and crushing strength were measured under controlled granulation moisture content.
• Tablets were compressed using punches with different tip curvatures (standard, deep, extra deep concave).
• Drug dissolution rates and tablet-to-tablet dissolution variability were assessed.

Main Results:

• Tablets containing lactose were more friable than those with microcrystalline cellulose.
• Replacing magnesium stearate with stearic acid reduced tablet friability.
• Extra deep concave punches resulted in lower tablet friability compared to standard or deep concave punches.
• Punch tip curvature was identified as a critical factor in reducing friability, but extra deep concave punches increased dissolution variability.

Conclusions:

• Formulation composition and tablet compression geometry significantly influence tablet friability.
• Stearic acid and specific punch designs offer viable methods to decrease tablet friability.
• Careful selection of punch geometry is necessary to balance friability reduction and dissolution consistency.