ASSESSING THE PARTICLE-SIZE OF A BROADLY DISPERSED POWDER BY COMPLEMENTARY TECHNIQUES

The experimental determination of reliable particle size distribution curves and statistical parameters of broad distributions is known to b e a difficult task. This problem is addressed here in an attempt to ch aracterize the granularity of three distinct batches of a pharmaceutic al powder (fenofibrate from Fournier Laboratories). The methodology co nsists in comparing the results, expressed in terms of surface based m ean diameter, as obtained by three complementary techniques, namely op tical microscopy image analysis, laser light low angle diffraction and surface area measurement by krypton physisorption. These techniques a re applied in parallel to the material of interest and to a certified reference material, a nearly spherical and narrowly distributed glass powder. (C) 1998 Elsevier Science B.V. All rights reserved.