Near-Infrared Spectroscopy to Determine Residual Moisture in Freeze-Dried Products: Model Generation by Statistical Design of Experiments

Process Analytical Technology Tools for Monitoring Pharmaceutical Unit Operations: A Control Strategy for Continuous Process Verification

“…Raman spectroscopy is a type of vibration spectroscopy. Various Raman laser sources offer a range of wavelengths (generally 785 nm), from the UV-VIS to near-infrared regions; the most common are visible light lasers [ 158 ]. In general, vibrations occur in chemical bonds that are not rigid, and materials can be characterized based on their molecular-vibration frequencies.…”

“…Raman spectroscopy is used to determine the molecule in the sample, and their intensity enables the calculation of the drug content of a particular sample. One of the main reasons for using PAT is to build and qualitatively analyze the specificity library of the raw material spectrum, including impurities in the sample [ 158 ]. Raman spectroscopy is ideally suited for PAT systems because it has the flexibility to operate on-line or in-line.…”

“…In the drying process, there is a need to achieve CPV by monitoring the drying temperature, drying rate, and chamber pressure, which are process parameters that affect CQAs in real-time. A PAT is primarily used during the freeze-drying process based on product temperature, chamber pressure, and sublimation flux estimates, which affect critical quality characteristics [ 158 ]. However, this can lead to process failure because it is challenging to grasp various process variations, including failure, due to unexpected changes in the set value of variables or the fluid mechanics of the chamber.…”

Near-infrared analysis of nanofibrillated cellulose aerogel manufacturing

“…NIR spectroscopy has been applied already in 1989 by Kamat et al in freeze-drying to determine the residual water content of freeze-dried sucrose solutions (Kamat et al, 1989). Recently, NIR spectroscopy has been used to monitor formulation changes in a multicomponent drug formulation during freeze-drying (Rosas et al, 2014), to predict residual water content of freeze-dried monoclonal antibody formulations (Clavaud et al, 2020), and to monitor the freeze-drying of ibuprofen for injection formulations (Preskar et al, 2021). We have previously applied a multipoint NIR system to monitor in-line the residual water contents of sucrose-water solutions during freeze-drying (Kauppinen et al, 2013).…”

Evaluation of the Robustness of A Novel NIR-based Technique to Measure the Residual Moisture In Freeze-dried Products

“…40 By following this approach, in case the model has been properly formulated, it can be used for a wider set of products. Another step in the direction of the minimization of the experimental activities for adjusting a NIRS model to a new product was done by Clavaud et al 41 and by Grohganz et al (2010). 42 The former included in the calibration a large range of product formulations and process parameters, according to a statistical design of experiments.…”