Chemoinformetrical evaluation of granule and tablet properties of pharmaceutical preparations by near-infrared spectroscopy

The purpose of this research was to apply near infrared spectrometry (NIR) with chemometrics to predict the change of pharmaceutical properties of antipyrine granules during granulation by regulation of the added water amount.MethodsThe various kinds of granules (mean particle size, 70–750 μm) were obtained from the powder mixture (1 g of antipyrine, 6 g of hydroxypropylcellulose, 140 g of lactose and 60 g of potato starch) by regulation of the added water amount (11–19 wt/wt.%) in a high-speed mixer. The granules were characterized as the mean particle size, angle of repose, compressibility, and tablet porosity and tablet hardness as parameters of pharmaceutical properties. To predict the pharmaceutical properties, NIR spectra of the granules were measured, and analyzed by principal component regression analysis (PCR). The mean particle size of the granules increased from 81 to 650 μm in diameter with an increase in the amount of water, and it is possible to make larger spherical granules with narrow particle size distribution using a high-speed mixer. The pharmaceutical properties, such as angle of repose, compressibility and porosity of the tablets decreased with an increase of added water, but the tablet hardness increased. The calibration models to evaluate particle size, angle of repose and tablet porosity and hardness were established by using PCR based on NIR spectra of granules, respectively. The correlation efficient constants of calibration curves for prediction of mean particle size, angle of repose, tablet porosity and tablet hardness were to be 0.9109, 0.8912, 0.7437 and 0.8064, respectively. It is possible that the pharmaceutical properties of the granule, such as mean particle size, angle of repose, tablet porosity and tablet hardness could be predicted by NIR-chemometric method.