title: Investigating dissolution performance critical areas on coated tablets: a case study using terahertz pulsed imaging.
abstract: During the process development of coated tablets, knowledge on the formation and the location of film coating 'weak spots' is a key factor to the success of the process and the resulting product batch. It is understood that the performance of the product batch may be greatly limited, and often compromised, by weak spots on the tablet film coat. This study uses circular, biconvex tablets to investigate the ability of terahertz pulsed imaging (TPI) to identify the affected areas on the tablet film coat that are critical for dissolution performance. From the TPI analysis we determined that the tablet central band exhibited the thinnest film coating, lowest coating density and highest surface roughness and thus was the performance limiting area of the film coating. Dissolution tests confirmed that the film coating on the tablet central band was indeed dissolution rate determining, with a faster mean dissolution time (MDT) of 7.4 h in comparison to 10.4 h for the convex top/bottom surface. TPI, as a nondestructive analytical technique, showed potential to be employed as a process analytical tool to probe film coating weak spots during film coating development and to assess the effect on the subsequent dissolution performance.
authors: School of Pharmacy, University of Otago, PO Box 56, Dunedin, New Zealand. lchh2@cam.ac.uk
authors: Louise
authors: L
authors: Ho
authors: Ronny
authors: R
authors: Müller
authors: Cornelia
authors: C
authors: Krüger
authors: Keith C
authors: KC
authors: Gordon
authors: Peter
authors: P
authors: Kleinebudde
authors: Michael
authors: M
authors: Pepper
authors: Thomas
authors: T
authors: Rades
authors: Yaochun
authors: Y
authors: Shen
authors: Philip F
authors: PF
authors: Taday
authors: J Axel
authors: JA
authors: Zeitler
mesh_terms: D003692:Delayed-Action Preparations; D008855:Microscopy, Electron, Scanning; D012995:Solubility; D013499:Surface Properties; D013608:Tablets, Enteric-Coated / Q000032:analysis / Q000737:chemistry* / Q000592:standards; D055069:Terahertz Imaging / Q000295:instrumentation / Q000379:methods*; D014867:Water / Q000737:chemistry
chemical_list: D003692:Delayed-Action Preparations; D013608:Tablets, Enteric-Coated; D014867:Water