Freeze-dried cake structural and physical heterogeneity in relation to freeze-drying cycle parameters.

Freeze-drying is the preferred method to manufacture proteins in their solid state thus the understanding of the relationship between cycle parameters and cake properties remains of great interest. The present study aims to investigate the influence of the freezing conditions in the material properties at different layers throughout the dried structure, in the presence and absence of a protein. Placebo and protein formulations were dried applying different cooling rates: slow, fast and fast cooling with annealing.

Milling induced amorphisation and recrystallization of α-lactose monohydrate.

Preprocessing of pharmaceutical powders is a common procedure to condition the materials for a better manufacturing performance. However, such operations may induce undesired material properties modifications when conditioning particle size through milling, for example. Modification of both surface and bulk material structure will change the material properties, thus affecting the processability of the powder.

AFM Colloidal Probe Measurements Implicate Capillary Condensation in Punch-Particle Surface Interactions during Tableting.

Adhesion of the powders to the punches is a common issue during tableting. This phenomenon is known as sticking and affects the quality of the manufactured tablets. Defective tablets increase the cost of the manufacturing process.

Determination of Interfacial Amorphicity in Functional Powders.

The nature of the surfaces of particles of pharmaceutical ingredients, food powders, and polymers is a determining factor for their performance in for example tableting, powder handling, or mixing. Changes on the surface structure of the material will impact the flow properties, dissolution rate, and tabletability of the powder blend. For crystalline materials, surface amorphization is a phenomenon which is known to impact performance.

Tablet mechanics depend on nano and micro scale adhesion, lubrication and structure.

Tablets are the most convenient form for drug administration. However, despite the ease of manufacturing problems such as powder adhesion occur during the production process. This study presents surface and structural characterization of tablets formulated with commonly used excipients (microcrystalline cellulose (MCC), lactose, mannitol, magnesium (Mg) stearate) pressed under different compaction conditions.

Micro-minicircle Gene Therapy: Implications of Size on Fermentation, Complexation, Shearing Resistance, and Expression.

The minicircle (MC), composed of eukaryotic sequences only, is an interesting approach to increase the safety and efficiency of plasmid-based vectors for gene therapy. In this paper, we investigate micro-MC (miMC) vectors encoding small regulatory RNA. We use a construct encoding a splice-correcting U7 small nuclear RNA, which results in a vector of 650 base pairs (bp), as compared to a conventional 3600 bp plasmid carrying the same expression cassette.