Stress-Dependent Particle Interactions of Magnesium Aluminometasilicates as Their Performance Factor in Powder Flow...

Area of Science:

• Pharmaceutical Sciences
• Materials Science
• Chemical Engineering

Background:

• Silicates are versatile pharmaceutical excipients used as glidants, porous carriers, and coating materials in oral solid drug delivery.
• Optimal formulations require a balance between good powder flow and compactibility, presenting challenges in managing inter-particle interactions.
• Magnesium aluminometasilicates (MAS) exhibit unique 'negative cohesivity' flow properties and potential as tablet binders.

Purpose of the Study:

• To investigate the particle interactions of magnesium aluminometasilicates (MAS) under a wide range of mechanical stress (kPa to MPa).
• To evaluate the multifunctional potential of MAS as pharmaceutical excipients.

Main Methods:

• Preparation of physical powder mixtures of MAS (Neusilin® US2, Neusilin® S2) and microcrystalline cellulose (Avicel® PH102) at varying MAS concentrations.
• Examination of powder rheology and compaction behavior under different pressure exposures.
• Analysis of particle interactions across a broad mechanical stress spectrum.

Main Results:

• Under normal conditions, MAS particles exhibit repulsive character and minimal contact surface area.
• Application of threshold pressure induces MAS particle destruction, leading to new surface formation and particle interactions.
• The intensity of MAS particle interactions increases with applied pressure and concentration in the mixture.

Conclusions:

• Magnesium aluminometasilicates demonstrate a pressure-dependent 'function switching' behavior, transitioning from glidant to binder.
• This adaptability makes MAS suitable as multifunctional excipients in oral solid dosage forms.
• Understanding these pressure-induced interactions is key to optimizing pharmaceutical formulations.