Determination of Figures of Merit for Near-Infrared, Raman and Powder X-ray Diffraction by Net Analyte Signal Analysis for a Compacted Amorphous Dispersion with Spiked Crystallinity

Abstract

With the growing interest in solubility enhancement of drugs via solid dispersion formulations, it is becoming more crucial to find appropriate analytical methods for detection of amorphous destabilization (i.e., crystallization). The objective of this work was to compare the performance of reflectance and transmittance near-infrared spectroscopy and Raman spectroscopy methods with powder X-ray diffraction. Specifically, the methods were compared on their ability to detect low concentrations (0–2 % w/w) of crystalline indomethacin-consolidated dispersions. Partial least squares regression and net analyte signal analyses were performed for the computation of figures of merit. Based on the calibration error statistics, all methods were suitable for the quantitative determination indomethacin content above 0.5 % (w/w) or 1 % (w/w) of drug content. However, the sensitivity, selectivity, limit of detection, and data collection time found for the near-infrared reflectance measurements provides the greatest promise for future online stability monitoring of consolidated dispersions.