Particle Size Analysis Of Powdered Aspirin Using The Saturn DigiSizer 5200

Particle size distribution analysis is frequently used to characterize pharmaceutical powders. Efficacy and dosage sizes are often correlated to median or mean particle diameters. Pharmaceutical production is often monitored using rapid particle size analysis typical of laser light scattering. The Saturn DigiSizer can be used to quickly provide high resolution particle size distribution analyses. Commercially available powdered aspirin samples are used to illustrate how particle size analysis may be used to monitor product quality.

Samples of powdered aspirin were purchased at a number of local pharmacies over a period of weeks to obtain different lots of powder to look at the differences between production lots. Several packets within a given package were analyzed to look for differences within the lot. Two packages of a single lot of a second aspirin brand were purchased to investigate differences in particle size distribution between brands, and between packages from the same lot. Again, multiple packets were analyzed from both packages.

All samples were added dry to the Liquid Sample Handling Unit of the Saturn DigiSizer, and were dispersed in odorless mineral spirits with two minutes of ultrasonic treatment using the probe built into the DigiSizer. A small amount of Micromeritics SediSperse A-11 was used to help disperse the powder. All samples were analyzed consecutively from 3 to 8 times each. The average of the individual tests was used in the following comparisons. The SPC features of the DigiSizer software were used to generate the control charts provided.