Near-infrared spectroscopy calibration model

Mtlller UA, Mertes B, Fischbacher C, Jagemann K-U, Danzer K (1997) Non-invasive blood glucose monitoring by means of near infrared spectroscopy methods for Improving the reliability of the calibration models. Int J Artific Organs 20 285... 

Parsimonious Calibration Models for Near-Infrared Spectroscopy using Wavelets and Scaling Functions. 

M. Alcala, J. Leon, J. Ropero, M. Blanco and R.J. Romanach, Analysis of low content drug tablets by transmission near infrared spectroscopy selection of calibration ranges according to multivariate detection and quantitation limits of PLS models, J. Pharm. Sci, 97(12), 5318-5327 (2007). 

The analytical utility of near-infrared spectroscopy can be illustrated by establishing and characterizing calibration models for the measurement of glucose in a set of aqueous solutions composed of glucose, lactate, urea, ascorbate, alanine, and triacetin. In this experiment, 80 different samples were prepared with randomized concentrations of each component ranging from 1 to 35 mM.6 Solute concentrations were randomized to minimize covariance between the different solute concentrations. All solutions were prepared in a pH 6.8 phosphate buffer solution. 

An attractive feature of near-infrared spectroscopy is the ability to extract information from multiple analytes from a single spectrum. The same spectra used above to measure glucose in this mixture of six components can be used to generate independent calibration models for the other matrix constituents. 

Near-infrared spectroscopy was used to quantitatively determine the phase composition of a compound capable of existing in two polymorphic forms even though the NIR spectra were fairly similar.79 Using a five-wavelength calibration model, nearly 100% recovery was obtained in a series of spiked calibration samples, with relative standard deviation values ranging from 0.1% to 0.9%. The authors concluded that the use of NIR spectroscopy... 

Near-infrared spectroscopy has been used to quantitate sulfathiazole Form-I and Form-Ill in binary physical mixtures in which one form was the dominant component.81 The spectra of each form exhibited sufficient differences that unique wavelengths of absorbance were easily attributable to each form. Excellent linearity in calculated versus actual compositions were obtained over the concentration range of 0-5% for either Form-I in Form-Ill, or for Form-Ill in Form-I. After considering appropriate calibration models, a limit of quantitation of approximately 0.3% was ultimately deduced. 

M. Boiret, L. Meunier, and Y.-M. Ginot, Tablet Potency of Tianeptine in Coated Tablets by Near infrared Spectroscopy Model Optimisation, Calibration Transfer and Confidence intervals, /. Pharm. Biomed. Anal., 54, 510 (2011). 

Transfer of Multivariate Calibration Models Based on Near-Infrared Spectroscopy... 

Smith, M.R., et al.. Optimisation of partial least squares regression calibration models in near-infrared spectroscopy A novel algorithm for wavelength selection. Analyst (Cambridge, United Kingdom), 128 1312-1319 (2003). 

Macho S, Rius A, Callao MR Larrechi MS. Monitoring ethylene content in heterophasic copolymers hy near-infrared spectroscopy standardisation of the calibration model. Anal Chim Acta 2001 445 213-220. 

Li, W. and Worosila, G. D. Quantitation of active pharmaceutical ingredients and excipients in powder blends using designed multivariate calibration models by near-infrared spectroscopy. Int. J. Pharm. 295 213-219, 2005. 

Maruo K, Oota T, Tsurugi M, Nakagawa T, Arimoto H, Hayakawa M, Tamura M, Ozaki Y, Yamada Y. Noninvasive near-infrared blood glucose monitoring using a calibration model built by a numerical simulation method trial application to patients in an intensive care unit. Applied Spectroscopy 2006, 60, 1423-1431. 

Near-infrared (NIR) spectroscopy is becoming an important technique for pharmaceutical analysis. This spectroscopy is simple and easy because no sample preparation is required and samples are not destroyed. In the pharmaceutical industry, NIR spectroscopy has been used to determine several pharmaceutical properties, and a growing literature exists in this area. A variety of chemoinfometric and statistical techniques have been used to extract pharmaceutical information from raw spectroscopic data. Calibration models generated by multiple linear regression (MLR) analysis, principal component analysis, and partial least squares regression analysis have been used to evaluate various parameters. 

Models are constructed in analytics to describe the relationship between responses and factors. This is, for example, important for optimization of analytical methods on the basis of response surface methods (cf. Section 4.2). Models are also needed for cahbration of analytical methods. There, calibration of a single analyte in dependence on one or several wavelengths might be of interest. If, in the first example, the straight-line model would be adequate, for the second task of multiwavelength spectroscopy, multivariate approaches are needed. Calibrations in the case of unselective analytical methods must also be performed. These methods are termed simultaneous multicomponent analysis. In near-infrared (NIR) spectroscopy, the contents of water and protein in whole grain wheat are determined that way. 

Follow-up work described by Van Eckeveld et al. (2) expanded the analytical techniques used during screening to also include the sonic speed, viscosity and near-infrared (NIR) spectroscopy. Several multivariate models were constructed based on a dedicated set of 29 lab-prepared calibration samples, covering MEA concentrations of 0 to 36 wt% and CO2 concentrations of 0.0 to 0.5 mol CO2 per mol MEA at temperatures of 40 and 55 °C. The models differed in the eombination of analytioal techniques... 

Beyer, J. and Steffens, K., Calibration models for determination of water content in pharmaceutical excipients using near-infiared spectroscopy (nirs), Pharm. Ind. (Germany), 65(2), 186-192, 1975. Sinsheimer, J.E. and Poswalk, N.M., Pharmaceutical applications of the near-infrared determination of water, J. Pharm. ScL, 57(11), 2007-2010, 1968. 

The purpose of this chapter is to provide a quick reference/overview to near-infrared (NIR) spectroscopy calibrationists on the important aspects of quantitative or qualitative calibration techniques as illustrated by the flow chart in Figure 7.1. The main task of the computer in NIR spectroscopy, aside from driving the instrument or collecting data, is to interpret the spectra using a variety of multivariate mathematical techniques. These techniques are used to produce a mathematical calibration model. Figure 7.2 illustrates the various sample sets used for testing calibration models and the conditions where recalibration is indicated. The purpose of the calibration model is... 

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