Evaluation of effect of the primary particle size on compactibility of spray-dried lactoses

Spray-dried lactose is one of the most used filler-binders in direct compaction of tablets. Spray-dried lactose is produced by spray-drying a suspension of α-lactose monohydrate crystals in a saturated aqueous solution of lactoses. The resulting product is composed of spherical particles, containing 80-85% crystals of α-lactose monohydrate (primary particles) and 15-20% amorphous lactose The compactibility of two commercial spray-dried lactoses, Pharmatose® DCL 11 (DCL11), prepared from α-lactose monohydrate with a median primary particle size of 34 µm and a new product, Pharmatose® DCL 14 (DCL14), prepared from 20 µm primary particles, were investigated

CLSM as Quantitative Method to Determine the Size of Drug Crystals in a Solid Dispersion

PURPOSE: To test whether confocal laser scanning microscopy (CLSM) can be used as an analytical tool to determine the drug crystal size in a powder mixture or a crystalline solid dispersion. METHODS: Crystals of the autofluorescent drug dipyridamole were incorporated in a matrix of crystalline mannitol by physical mixing or freeze-drying. Laser diffraction analysis and dissolution testing were used to validate the particle size that was found by CLSM. RESULTS: The particle size of the pure drug as determined by laser diffraction and CLSM were similar (D(50) of approximately 22 μm). CLSM showed that the dipyridamole crystals in the crystalline dispersion obtained by freeze-drying of less concentrated solutions were of sub-micron size (0.7 μm), whereas the crystals obtained by freeze-drying of more concentrated solutions were larger (1.3 μm). This trend in drug crystal size was in agreement with the dissolution behavior of the tablets prepared from these products. CONCLUSION: CLSM is a useful technique to determine the particle size in a powder mixture. Furthermore, CLSM can be used to determine the drug crystal size over a broad size distribution. A limitation of the method is that the drug should be autofluorescent

Performance of Tablet Splitters, Crushers, and Grinders in Relation to Personalised Medication with Tablets

Swallowing problems and the required dose adaptations needed to obtain optimal pharmacotherapy may be a hurdle in the use of tablets in daily clinical practice. Tablet splitting, crushing, or grinding is often applied to personalise medication, especially for the elderly and children. In this study, the performance of different types of (commercially available) devices was studied. Included were splitters, screwcap crushers, manual grinders, and electric grinders. Unscored tablets without active ingredient were prepared, with a diameter of 9 and 13 mm and a hardness of 100–220 N. Tablets were split into two parts and the difference in weight was measured. The time needed to pulverise the tablets (crush time) was recorded. The residue remaining in the device (loss) was measured. The powder was sieved to obtain a particle fraction >600 µm and <600 µm. The median particle size and particle size distribution of the later fraction were determined using laser diffraction analysis. Splitting tablets into two equal parts appeared to be difficult with the devices tested. Most screwcap grinders yielded a coarse powder containing larger chunks. Manual and especially electric grinders produced a finer powder, making it suitable for administration via an enteral feeding tube as well as for use in individualised preparations such as capsules. In conclusion, for domestic and incidental use, a screwcap crusher may provide sufficient size reduction, while for the more demanding regular use in hospitals and nursing residences, a manual or electric grinder is preferred

Tableting properties of an improved spray-dried lactose

Spray-dried lactose is one of the most widely used filler-binders for direct compaction. The compactibility is a function of both primary particle size and the presence of amorphous lactose. Commercially available spray-dried lactose contains 15-20% amorphous lactose and 80-85% alpha-lactose monohydrate. A better understanding of the relationship between particle structure, physical properties and mechanisms of consolidation and compaction enabled an improved spray-dried lactose to be developed. The agglomerates of the improved product contain smaller primary a-lactose monohydrate particles than those of regular products. The present study shows that the improved spray-dried lactose has better compaction properties than regular spray-dried lactose