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AAPS PharmSciTech. 2006 December; 7(4): E125–E132.
Published online 2014 March 30. doi:  10.1208/pt0704102
PMCID: PMC2750339

Scale-up of a pan-coating process


The purpose of this work was to develop a practical scale-up model for a solvent-based pan-coating process. Practical scale-up rules to determine the key parameters (pan load, pan speed, spray rate, air flow) required to control the process are proposed. The proposed scale-up rules are based on a macroscopic evaluation of the coating process. Implementation of these rules does not require complex experimentation or prediction of model parameters. The proposed scale-up rules were tested by conducting coating scale-up and scale-down experiments on 24-inch and 52-inch Vector Hi-coaters. The data demonstrate that using these rules led to similar cumulative drug release profiles (f2[dbl greater-than sign]50; and P Analysis of Variance [PANOVA][dbl greater-than sign]0.05 for cumulative percentage of drug released after 12 hours [Cum 12] from tablets made at 24- and 52-inch scales. Membrane characteristics such as opacity and roughness were also similar across the 2 scales. The effects of the key process variables on coat weight uniformity and membrane characteristics were also studied. Pan speed was found to be the most significant factor related to coating uniformity. Spray droplet size was found to affect the membrane roughness significantly, whereas opacity was affected by the drying capacity.

Keywords: Pan coating, scale-up, scale-down, similarity, solvent coating, drug release, opacity

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.
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