Benchtop and different miniaturized near-infrared spectrometers application study: Calibration transfer and 2D-COS...

The demand for miniaturized near-infrared (NIR) spectrometers has surged due to their potential for in-situ analysis. However, their predictive accuracy has not yet matched that of traditional benchtop instruments. This study evaluates the effectiveness of rapid quantitative moisture analysis in hydroxypropyl methylcellulose (HPMC) using a benchtop spectrometer, Antaris II from Thermo Fisher Scientific Inc., and five miniaturized spectrometers (MicroNIR 1700 from Viavi Solutions, OTO-SW2540 from OtOPhotonics, IAS DLP 1700 from Dallas, NIRONE Sensor 2.2 from Helsinki, and NIRS M1800 from Alian Optoelectronics). This study employed an Improved Principal Component Analysis (IPCA) transfer method to standardize spectra from the diverse miniaturized NIR spectrometers, facilitating calibration transfer across different spectroscopic technologies. The benchtop (Antaris II) delivered the most superior results, indicating that miniaturized spectrometers must refine their methodologies to approach the predictive performance of benchtop counterparts. Further, this work conducted a two-dimensional correlation spectroscopy (2D-COS) analysis on the spectra from various spectrometers. This analysis bolstered the partial least squares regression (PLSR) model, highlighting discrepancies between miniaturized and benchtop spectrometers and deepening understanding of the factors influencing the PLSR models. The IPCA leverages the benchtop model to enhance the precision and reliability of miniaturized NIR spectrometers. This innovative and versatile research approach aims to further optimize the performance of miniaturized NIR spectrometers for specific applications, representing a significant step forward in their development.