The scale-up of pharmaceutical tablet film coating is examined within the context of maintaining the tablet elegance observed at the pilot scale. Tablet elegance was defined by several physical characteristics: surface finish, tablet damage, and color uniformity. Successful bridging from 24" (pilot) to 64" (commercial) diameter pans required a novel scaling rationale based upon a constant spray flux, bed temperature, and tablet coating mass variance. This new method incorporates tablet variables and was demonstrated across an eight fold range of core tablet mass. In contrast, scale-up based on literature recommendations of controlling process parameters - outlet temperature or relative humidity, spray/air ratio, and peripheral drum speed was relatively unsuccessful.

References:

Turton, R., Cheng, X. X. (2005). "The scale-up of spray coating processes for granular solids and tablets." Powder Technology, 150, 78-85

Levin, M, ed. (2002). "Pharmaceutical Process Scale-up." Drugs and the Pharmaceutical Sciences, vol. 118, Marcel Dekker, Inc.