Stress-Dependent Particle Interactions of Magnesium Aluminometasilicates as Their Performance Factor in Powder Flow and Compaction Applications

Abstract

In the pharmaceutical industry, silicates are commonly used excipients with different application possibilities. They are especially utilized as glidants in low concentrations, but they can be used in high concentrations as porous carriers and coating materials in oral solid drug delivery systems. The desirable formulations of such systems must exhibit good powder flow but also good compactibility, which brings opposing requirements on inter-particle interactions. Since magnesium aluminometasilicates (MAS) are known for their interesting flow behavior reported as “negative cohesivity” yet they can be used as binders for tablet compression, the objective of this experimental study was to investigate their particle interactions within a broad range of mechanical stress from several kPa to hundreds of MPa. Magnesium aluminometasilicate (Neusilin® US2 and Neusilin® S2)-microcrystalline cellulose (Avicel® PH102) physical powder mixtures with varying silicate concentrations were prepared and examined during their exposure to different pressures using powder rheology and compaction analysis. The results revealed that MAS particles retain their repulsive character and small contact surface area under normal conditions. If threshold pressure is applied, the destruction of MAS particles and formation of new surfaces leading to particle interactions are observed. The ability of MAS particles to form interactions intensifies with increasing pressure and their amount in a mixture. This “function switching” makes MAS suitable for use as multifunctional excipients since they can act as a glidant or a binder depending on the applied pressure.

Amalgamation of Solid Dispersion and Melt Adsorption Techniques For Augmentation of Oral Bioavailability of Novel Anticoagulant Rivaroxaban

“…It has been described that Neusilin US2 is porous in nature with numerous inter and intra particle apertures exists on its surface that can contribute enormous surface area and eventually helps in greater adsorption (47). Further, the SEM images in Figure 4 also demonstrated total adsorption of PEG 4000 and RXN on the surface of Neusilin US2.…”

Enhancement of Pioglitazone Hydrochloride Solubility Through Liquisolid Compact Formulation Using Novel Carrier Neusilin US2

“…Liquisolid compacts are pills or tablets that release immediately or continuously after being swallowed, along with the addition of any necessary adjuvants for tablets or encapsulating them [2]. With a neutral pH, Neusilin® US2 is a synthetic, amorphous magnesium aluminum oximetasilicate that can be utilized for both wet granulation and direct compression of solid dosage forms [3]. Only if a maximum liquid load on the carrier material is not exceeded can one obtain an acceptable flowing and compressible liquid-solid system depending on the excipient ratio (R) of the powder substrate.…”

Silica and Silica-Based Materials for Biotechnology, Polymer Composites, and Environmental Protection

“…These materials can also be used in the pharmaceutical industry as glidants in low concentrations, as well as in high concentrations as porous carriers and coating materials in oral solid drug-delivery systems. A study performed by Kominova et al [ 6 ] demonstrated the characterization of commercially available magnesium aluminometasilicates (MAS) modified by microcrystalline cellulose as a potential glidant and/or binder. It was reported that the MAS concentration and pressure applied have a significant effect on MAS behavior.…”