Baylor University

Other

Dennis H Rabbe

Kenneth W Busch

Marianna A Busch

Carlos Calleja-Amador

A method for determining sugar concentration using spectropolarimetry and multivariate regression modeling A set of fixed polarizers are used in association with a spectrometer, which enables the measurement of optical rotation as absorbance values over a range of wavelengths. The adverse effects of color within the samples is corrected by measuring a background level of absorbance that is not due to optical rotation and using this as a baseline. A regression model is then developed for predicting sugar concentration in unknown samples. This method is effective even if the sample is colored.

Spectroscopic determination of sucrose

A new method and strategy for the quantitative determination of enantiomeric purity that combines polarimetry, spectroscopy, and chemometric modeling. Spectral data is collected after a light beam is passed through a first polarimeter, a sample of a chiral compound, and a second polarimeter oriented at a 45 degree angle relative to the first polarimeter. The spectral data for samples of known enantiomeric composition is subjected to a type of multivariate regression modeling known as partial least squares ('PLS-1') regression. The PLS-1 regression produces a mathematical model that can be used to predict the enantiomeric composition of a set of samples of unknown enantiomeric purity.

Spectroscopic determination of enantiomeric purity

A dispersive, diffraction grating, NIR spectrometer that automatically calibrates the wavelength scale of the instrument without the need for external wavelength calibration materials is shown. The device shows: 1) a low power He&#x2014;Ne laser at right angles to the source beam of the spectrometer; 2) a folding mirror to redirect the collimated laser beam so that it is parallel to the source beam; 3) the tendency of diffraction gratings to produce overlapping spectra of higher orders; 4) a 'polka dot' beam splitter to redirect the majority of the laser beam toward the reference detector; 5) PbS detectors and 6) a software routine written in Lab VIEW that automatically corrects the wavelength scale of the instrument from the positions of the 632.8 nm laser line in the spectrum.

Dispersive near-infrared spectrometer with automatic wavelength calibration

The present invention is a dispersive, diffraction grating, NIR spectrometer that automatically calibrates the wavelength scale of the instrument without the need for external wavelength calibration materials. The invention results from the novel combination of: 1) a low power He&mdash;Ne laser at right angles to the source beam of the spectrometer; 2) a folding mirror to redirect the collimated laser beam so that it is parallel to the source beam; 3) the tendency of diffraction gratings to produce overlapping spectra of higher orders; 4) a &ldquo;polka dot&rdquo; beam splitter to redirect the majority of the laser beam toward the reference detector; 5) PbS detectors and 6) a software routine written in Lab VIEW that automatically corrects the wavelength scale of the instrument from the positions of the 632.8 nm laser line in the spectrum.

Growing community of inventors

Crawford, TX, United States of America

Dennis H Rabbe