Particle Size and Distribution
Particle size distribution, the measure of subdivision of a solid, can be directly correlated with uniformity of quality and performance. Primary particle size is a physicochemical property that may impact temporal chemical and physical effects such as stability and aggregation. In addition, particle size influences the motion of the powder or suspension that may be required during processing or as an endpoint of the dosage form performance.
Descriptions of particle size are based on assumptions about the dimension being measured. Moreover, since particles in a finely divided solid exist in a range of sizes, assumptions are made about their distribution and mathematical functions that best approximate the materials under scrutiny. It is important to acknowledge the assumptions and their limitations in accurately describing a particle size distribution. Comparing the definition adopted with the process or performance characteristic desired maximizes the likelihood of setting relevant product specifications.
- 1.Mullin J. Crystallization. 3rd ed. Oxford, UK: Butterworth-Heinemann; 1993.Google Scholar
- 3.Sieving AT. Particle size measurement. New York: Chapman and Hall; 1990. p. 192.Google Scholar
- 4.Allen T. Particle size, shape and distribution. Particle size measurement. New York: Chapman and Hall; 1990. p. 124–91.Google Scholar
- 5.Russ J. The image processing handbook. 4th ed. Boca Raton: CRC Press; 2002.Google Scholar
- 6.Adamson A, Gast A. Physical chemistry of surfaces. New York: Wiley; 1997.Google Scholar
- 9.Sinko P. Martin’s physical pharmacy and pharmaceutical sciences. 7th ed. Philadelphia: Wolters and Kluwer; 2017.Google Scholar
- 10.Schimpf M, Caldwell K, Giddings J. Field-flow fractionation. New York: Wiley; 2000.Google Scholar
- 11.Lodge JP, Chan T. Cascade impactor sampling and data analysis. Akron: American Industrial Hygiene Association; 1986.Google Scholar
- 12.Tougas T, Mitchell J, Lyapustina S, editors. Good cascade impactor practices, AIM and EDA for orally inhaled products. New York: Springer; 2013.Google Scholar
- 17.Stockham J. What is particle size: the relationship among statistical diameters. In: Stockham J, Fochtman E, editors. Particle size analysis. Ann Arbor: Ann Arbor Press; 1977.Google Scholar