Wet granulation process is a unit operation used widely in the food, detergent and pharmaceutical industries where the moisture is a critical factor since it affects the growing of granules. The size is important because it affects the granule flowability, drug delivery, and tablet hardness.

Near Infrared (NIR) is being evaluated as an in-line technique for monitoring the moisture of pharmaceutical powders during the wet granulation process; this technology provides a non-invasive and non-destructive analytical method that would be suitable for pharmaceutical process analytical technology (PAT).

In previous research, the off-line measures of wet granulation process using NIR indicated high precision and thus it is expected that in-line measures give similar results. Full in-line and off-line NIR spectra of pharmaceutical powders at different levels of binder were measured, and a multivariate calibration model will be used to determine moisture in the wet granulation process.

Keywords: Wet granulation; Moisture measurement; Near infrared; PAT; calibration model