Evidence-based nanoscopic and molecular framework for excipient functionality in compressed orally disintegrating tablets

Effect of magnesium stearate solid lipid nanoparticles as a lubricant on the properties of tablets by direct compression

This study discusses the lubricant properties of magnesium stearate solid lipid nanoparticles (MgSt-SLN) and their effect on the tabletability, mechanical properties, disintegration, and acetaminophen-model dissolution time of microcrystalline cellulose (MCC) tablets prepared by direct compression. The behavior of MgSt-SLN was compared to reference material (RM) to identify advantages and drawbacks. The nanoprecipitation/ion exchange method was employed to prepare the MgSt-SLN. Particle size, zeta potential, specific surface area, morphology, and true density were measured to characterize the nanosystem. The MgSt-SLN particle sizes obtained were 240 ± 5 nm with a specific surface area of 12.2 m2/g. The MCC tablets with MgSt-SLN presented a reduction greater than 20 % in their ejection force, good tabletability, higher tensile strength, lower disintegration delay, and marked differences in acetaminophen dissolution when compared to the RM. The reduced particle size of the magnesium stearate seems to offer a promising technological advantage as an efficient lubricant process that does not affect the properties of tablets.

Processability of mesoporous materials in fused deposition modeling for drug delivery of a model thermolabile drug

The incorporation of drug-loaded mesoporous materials in dosage forms prepared with fused deposition modeling (FDM) has shown the potential to solve challenges relating to additive manufacturing techniques, such as the stability of poorly-soluble drugs in the amorphous state. However, the addition of these non-melting mesoporous materials significantly affects the mechanical properties of the filament used in FDM, which in turn affects the printability of the feedstock material. Therefore, in this study a full-factorial experimental design was utilized to investigate different processing parameters of the hot melt extrusion process, their effect on various mechanical properties and the potential correlation with the filaments' printability. The thermolabile, poorly-soluble drug ibuprofen was utilized as a model drug to assess the potential of two mesoporous materials, Mesoporous Magnesium Carbonate (MMC) and a silica-based material (MCM-41), to thermally protect the loaded drug. Factorial and principal components analysis displayed a correlation between non-printable MCM-41 filaments and their mechanical properties where printable filaments had a maximum stress >7.5 MPa and a Young's modulus >83 MPa. For MMC samples there was no clear correlation, which was in large part attributed to the filaments' inconsistencies and imperfections. Finally, both mesoporous materials displayed a thermal protective feature, as the decomposition due to the thermal degradation of a significant portion of the thermolabile drug was shifted to higher temperatures post-loading. This highlights the potential capability of such a system to be implemented for thermosensitive drugs in FDM applications.

3D-Printed Mesoporous Carrier System for Delivery of Poorly Soluble Drugs

Fused deposition modelling (FDM) is the most extensively employed 3D-printing technique used in pharmaceutical applications, and offers fast and facile formulation development of personalized dosage forms. In the present study, mesoporous materials were incorporated into a thermoplastic filament produced via hot-melt extrusion and used to produce oral dosage forms via FDM. Mesoporous materials are known to be highly effective for the amorphization and stabilization of poorly soluble drugs, and were therefore studied in order to determine their ability to enhance the drug-release properties in 3D-printed tablets. Celecoxib was selected as the model poorly soluble drug, and was loaded into mesoporous silica (MCM-41) or mesoporous magnesium carbonate. In vitro drug release tests showed that the printed tablets produced up to 3.6 and 1.5 times higher drug concentrations, and up to 4.4 and 1.9 times higher release percentages, compared to the crystalline drug or the corresponding plain drug-loaded mesoporous materials, respectively. This novel approach utilizing drug-loaded mesoporous materials in a printed tablet via FDM shows great promise in achieving personalized oral dosage forms for poorly soluble drugs.

In situ nanoscale visualization of solvent effects on molecular crystal surfaces

Atomic force microscopy and molecular dynamics simulations probed the crystallinity and hydrophobicity of a paracetamol crystal surface in water–ethanol mixtures. We observe the formation of a dynamic heterogenous disordered surface (DHDS) layer.

Microparticle surface layering through dry coating: impact of moisture content and process parameters on the properties of orally disintegrating tablets

Objectives

The aim of this study was to investigate the influence of process parameters during dry coating on particle and dosage form properties upon varying the surface adsorbed moisture of microcrystalline cellulose (MCC), a model filler/binder for orally disintegrating tablets (ODTs).

Methods

The moisture content of MCC was optimised using the spray water method and analysed using thermogravimetric analysis. Microproperty/macroproperty assessment was investigated using atomic force microscopy, nano-indentation, scanning electron microscopy, tablet hardness and disintegration testing.

Key findings

The results showed that MCC demonstrated its best flowability at a moisture content of 11.2% w/w when compared to control, comprising of 3.9% w/w moisture. The use of the composite powder coating process (without air) resulted in up to 80% increase in tablet hardness, when compared to the control. The study also demonstrated that surface adsorbed moisture can be displaced upon addition of excipients during dry processing circumventing the need for particle drying before tabletting.

Conclusions

It was concluded that MCC with a moisture content of 11% w/w provides a good balance between powder flowability and favourable ODT characteristics.