A novel in-line NIR spectroscopy application for the monitoring of tablet film coating in an industrial scale process

► Heart-shaped tablets were coated with a thin HPMC film up to approx. 28 μm on the tablet face. ► In different PCA models the dominating factors and their spectral effects of each coating step could be identified. ► The distinct separation of HPMC coating growth and tablet moisture in different PCs was elaborated. ► PLS models were developed for the determination of tablet moisture, tablet weight gain and coating growth. ► At-line NIR Chemical Imaging in combination with PLSDA verified the coating growth information.