Determination of API content in a pilot-scale blending by near-infrared spectroscopy as a first step method to process line implementation.

Near infrared (NIR) spectroscopy was used for estimation of powder blend homogeneity and manufacturing control of a medicinal product powder mixture containing active pharmaceutical ingredient (API). Aiming at initiating a Process Analytical Technology (PAT) activity, the first step was a stationary mode at-line evaluation. In this, the content of pharmaceutical active compound in the powder mixtures intended to the direct tabletting was estimated based on recorded NIR spectra. Five formulations containing different quantities of API were prepared and analyzed also by a reference method--UV-Vis spectroscopy. A chemometric model was developed for calculation of the API amount in the mixtures. The Principal Component Regression (PCR) and Partial Least Squares (PLS) algorithms were used to obtain a model useful in further implementation for the PAT recommendations, into in-line blending control.