Deformation behavior of crystallized mannitol during compression using a rotary tablet press simulator.

Area of Science:

• Pharmaceutical Sciences
• Materials Science
• Chemical Engineering

Background:

• Mannitol is a key pharmaceutical excipient for oral tablets.
• Understanding mannitol's mechanical properties is crucial for optimizing tablet formulations.
• Mannitol exists as native crystals or textured particles for tableting.

Purpose of the Study:

• To investigate the deformation mechanism of native mannitol crystals.
• To evaluate the influence of particle size on mannitol's mechanical behavior during compression.

Main Methods:

• Pharmaco-technical and compression studies were conducted on mannitol with mean diameters of 160 µm, 50 µm, and 25 µm.
• HECKEL and WALKER mathematical models were applied to analyze deformation.
• Lactose and microcrystalline cellulose served as brittle and plastic references.
• Particle-size analysis and Scanning Electron Microscopy (SEM) were used to assess fragmentation.

Main Results:

• Crystalline mannitol exhibited a deformation mechanism similar to brittle materials, based on Yield Pressure (Py) and WALKER coefficient (W) values.
• Mannitol particles, particularly those of 160 µm, demonstrated significant fragmentation under high pressures.
• SEM confirmed particle fragmentation after high-pressure compression tests.

Conclusions:

• Native crystalline mannitol behaves as a brittle material in tableting processes.
• Particle size significantly impacts mannitol's susceptibility to fragmentation, with larger particles being more vulnerable.
• These findings are essential for formulators to control mannitol's mechanical behavior in tablet production.