Near-infrared spectrophotometr

Bouveresse, E. Massart, D.L. Modified algorithm for standardization of near-infrared spectrophotometric instruments. Anal. Chem. 1995, 67, 1381-1389. 

Takeuchi,T., Tsuge.S., Sugimura, Y. Near-infrared spectrophotometric analysis of ethylene-propylene copolymers. Anal. Chem. 41, 184-186 (1969). 

O. Y. Rodionova and A. L. Pomerantsev, Near Infrared Spectrophotometric Comparison of Authentic and Susp>ect Pharmaceuticals, Trends Anal. Chem., 29, 795 (2010). 

Strait, L.A. and Hrenoff, M.K., Near-infrared spectrophotometric study of hydrogen bonding in primary aliphatic amines, Spectrosc. Lett., 8, 165-174, 1975. 

Zappala, A.R and Post, A., Rapid near-infrared spectrophotometric determination of Meprobamate in pharmaceutical preparations, J. Pharm. ScL, 66(2), 292-293, 1977. 

Takeuchi, T.S.T. and Y. Sngimura, Near-infrared Spectrophotometric Analysis of Ethylene-Propylene Copolymers. Ana/. Chem., 1969.41 184-186. 

Infrared Spectrophotometry. The isotope effect on the vibrational spectmm of D2O makes infrared spectrophotometry the method of choice for deuterium analysis. It is as rapid as mass spectrometry, does not suffer from memory effects, and requites less expensive laboratory equipment. Measurement at either the O—H fundamental vibration at 2.94 p.m (O—H) or 3.82 p.m (O—D) can be used. This method is equally appticable to low concentrations of D2O in H2O, or the reverse (86,87). Absorption in the near infrared can also be used (88,89) and this procedure is particularly useful (see Infrared and raman spectroscopy Spectroscopy). The D/H ratio in the nonexchangeable positions in organic compounds can be determined by a combination of exchange and spectrophotometric methods (90). 

Fig. 4. H-dependence of the visible absorption spectrum of bovine Co(II) carbonic anhydrase. The broken curve represents the basic spectral form, from ref. (58) (near infrared) and at pH 11.6 (visible). The solid curves were obtained in imidazole-sulfate buffers, ionic strength 0.1, pH 7.80, 7.00, 6.55, 6.10, respectively. The spectrum of lowest intensity was obtained by extrapolation and represents the acidic spectral form. Insert Spectrophotometric titration at 640 nm. The curve was calculated for the titration of a single group with pKa = 6.6...

Other spectrophotometric techniques have been reported for the analysis of spironolactone. Near infrared diffuse reflectance first-derivative spectroscopy was used for determination of spironolactone in pharmaceutical dosage forms [30]. Readings were taken at 15 nm intervals, and then 81 absorbance readings were imput into a computer for principal component analysis. 

Watson, C.A., Near infrared reflectance spectrophotometric analysis of agricultural... 

Nowadays, spectrophotometry is regarded as an instrumental technique, based on the measurement of the absorption of electromagnetic radiation in the ultraviolet (UV, 200-380 nm), visible (VIS, 380-780 nm), and near infrared region. Inorganic analysis uses UV-VIS spectrophotometry. The UV region is used mostly in the analysis of organic compounds. Irrespective of their usefulness in quantitative analysis, spectrophotometric methods have also been utilized in fundamental studies. They are applied, for example, in the determination of the composition of chemical compounds, dissociation constants of acids and bases, or stability constants of complex compounds. 

A. Picarelli, M. Greco, F. Di Giovambattista, A. Ramazzotti, C. Cedrone, E. Coarzziari, and A. Torsoli. Quantitative determination of faecal fat, nitrogen and water by means of a spectrophotometric technique near infrared reflectance analysis (NIRA). Assessment of its accuracy and reproducibility compared with chemical methods. Clin. Chim. Acta 234 147 (1995). 

Spectrophotometric investigation of the UV, visible, and near-infrared regions made possible the determination of the electronic spectra of each individual species and, thus, provided information about the solvation of the copper(II)-chloro complexes in DMF. The matrix rank treatment of more than 1000 spectrophotometric data demonstrates the presence of a minimum of four absorbing species the free copper ion and three chloro complexes. 

This section provides correlation charts and operational information for the design and interpretation of ultraviolet-visible spectrophotometric (UV-Vis) measurements. While UV-Vis is perhaps not as information-rich as infrared or nuclear magnetic resonance, it nonetheless has value in structure determination and sample identification. Moreover, it is extremely valuable in quantitative work. Typical UV-Vis instruments cover not only the UV and visible spectrum, but the near-infrared as well. Although there is overlap among the ranges, the approximate breakdown is ... 

N. Okazaki, K. Fukuda, Y. Kizaki, S. Kobayashi. Estimation of true polishing ratio of rice by near infrared reflectance spectrophotometric analysis. J Brew Soc Japan 86(4) 299-303, 1991. (in Japanese)... 

The process is usually monitored spectrophotometrically. Although other wavelengths such as 415 and 645 nm can be used in the ABTS-based assay, the near-infrared region at 734 nm is preferred due to less interference from plant pigments and sample turbidity [16]. Nevertheless, lower detection limits are achieved by monitoring the ABTS... 

The optical properties of pigments in the near infrared were studied by Taylor Di Bernardo reported anomalous spectrophotometric behavior of copper phthalocyanine—benzidine yellow mixtures. Brode and Wyman presented the absorption spectra of ten thio-indigo dyes in benzene and chloroform and discussed the effect of irradiation upon their cis-trans equilibria they also presented the spectra of nine of these dyes in H2SO4 in the range 210-800 m/i. 

G. Dejardin, J. Jarin, and M. Peyron, Apparatus for the Spectrophotometric Study of Weak Rays in the Near Infrared, Comp. rend. 238, 224-226, 1954. 

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