Validating AIM-Based Instrumentation and Associated Measurement Techniques - Good Cascade Impactor Practices, AIM and EDA for Orally Inhaled Products - page 310

Fig. 10.31 Size-related metrics from FSI with silicone-oil-coated collection surfaces with equiva-
lent NGI-generated metrics ( From [ 38 ]— courtesy of D. Russell-Graham )
Fig. 10.32 DoE for dry
powder blending parameters
investigated by FSI ( From
[ 38 ]— courtesy of
D. Russell-Graham )
fine lactose content and blend speed. Five DPI formulations were prepared: A, B, C,
and D mark the four extremes of the experimental range defined by high (15%) and
low (10%) fine lactose content and high (550 rpm) and low (430 rpm) blend speed,
while E lies in the center of the defined space (Fig. 10.32 ). Theoretically, FPM <5.0μm
would be expected to increase with increasing fine lactose content and increasing
blend speed, excipient content being the dominating effect, giving a ranking for the
formulations of A, B, E, C, and D, with A expected to deliver superior performance.
The FSI results correctly identified the influence of excipient fine content
(Table 10.12 ) but failed to indicate any statistical difference between formulations