Near-infrared spectroscopy moisture content determination

Savage, M., Torres, J., Franks, L., Mase-car, B., Hotta, J. Determination of adequate moisture content for efficient dry-heat viral inactivation in lyophilized factor VIII by loss on drying and by near infrared spectroscopy. Biologicals 26, No. 2,119-124,1998... 

Near-Infrared Spectroscopy. Near-infrared (NIR) spectroscopy is a technique that has been around for some time but, like NMR spectroscopy, has only recently been improved and developed for on-line applications. Near-infrared analysis (NIRA) is a nondestructive technique that is versatile in the sense that it allows many constituents to be analyzed simultaneously 112, 113). The NIR spectrum of a sample depends upon the anharmonic bond vibrations of the constituent molecules. This condition means that the temperature, moisture content, bonding changes, and concentrations of various components in the sample can be determined simultaneously. In addition, scattering by particles such as sand and clay in the sample also allows (in principle) the determination of particle size distributions by NIRA. Such analyses can be used to determine the size of droplets in oil-water emulsions. 

M. Manley, L. Van Zyl, B. G. Osborne. Using Fourier transform near infrared spectroscopy in determining kernel hardness, protein and moisture content of whole wheat flour. J Near Infrared Spectrosc 10 71—76, 2002. 

The optimal moisture content of the dried granulation needs to be determined. High moisture content can result in (1) tablet picking or sticking to tablet punch surfaces and (2) poor chemical stability as a result of hydrolysis. An overdried granulation could result in poor hardness and friability. Moisture content analysis can he performed using the conventional loss-on-drying techniques or such state-of-the-art techniques as near infrared (NIR) spectroscopy. 

Lin and Hsu [1.85] described the determination of residual moisture in protein pharmaceuticals in sealed glass vials by near-infrared (NIR) spectroscopy. Five proteins were studied recombinant humanized monoclonal antibody (rhuMAb) E25, rhuM-Ab HER2, rhuMAb CDlla, TNKase and rt-PA. Higher moisture contents (RM) were obtained by adding appropriate amounts of MilliQ water to the wall of the vial in a... 

Several applications can be found in literature regarding the use of NIR for the paediction of the main physical and rheological parameters of pasta and bread. De Temmerman et al. in 2007 proposed near-infrared (NIR) reflectance spectroscopy for in-line determination of moisture concentrations in semolina pasta immediately after the extrusion process. Several pasta samples with different moisture concentrations were extruded while the reflectance spectra between 308 and 1704 ran were measured. An adequate prediction model was developed based on the Partial Least Squares (PLS) method using leave-one-out cross-validation. Good results were obtained with R2 = 0,956 and very low level of RMSECV. This creates opportunities for measuring the moisture content with a low-cost sensor. 

W. R. Windham, S. E. Kays, F. E. Barton, n. Effect of cereal product residual moisture content on total dietary fiber determined by near-infrared reflectance spectroscopy, J. Agric. Food Chem. 45 140-144, 1997. 

R. L. Wehling, M. M. Pierce. Determination of moisture content in Cheddar cheese by near infrared reflectance spectroscopy. J Assoc Off Anal Chem 71 571-574,1988. 

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