Measurement of the particle size of tablet excipients with the aid of video recording.

Abstract

A method for the determination of the particle size of tablet excipients involving the use of video recording of microscopic examination of powders is described. The projected area of the particle profile was measured, and Feret's diameter and shape factors such as the elongation ratio, bulkiness factor, and surface factor were determined. Starch particles are the smallest among the excipients studied. Primojel particles are two to three times larger (Feret's diameter) and have up to 10 times greater projected areas. Particles of Avicel PH101, Ac-Di-Sol, Nymcel ZSD16 and ZSB10, and Polyplasdone XL have an irregular surface which results in large differences between the projected area diameter and the perimeter diameter. Particles of Nymcel and Ac-Di-Sol have the highest elongation ratio because of their cylindrical shape. Both Primojel and Starch have a low surface factor because of their spherical shape. This video-recording method is a simple system to observe, record, store, and retrieve particle-size data from microscopic examination of tablet excipients.