Optics: measuring and testing – By dispersed light spectroscopy – With raman type light scattering
Reexamination Certificate
1999-06-29
2001-10-23
Evans, F. L. (Department: 2877)
Optics: measuring and testing
By dispersed light spectroscopy
With raman type light scattering
Reexamination Certificate
active
06307625
ABSTRACT:
TECHNICAL FIELD
This invention relates generally to measuring and testing by dispersed light spectroscopy with Raman type light scattering, and more particularly to Raman spectroscopy for the determination of carbon-halogen and fluorooorganic compounds.
BACKGROUND
Qualitative and quantitative analysis of fluoroorganic compounds is an important practical task. Fluoroorganic compounds are widely used in the pharmaceutical industry. About one-third of all newly patented drugs contain carbon-fluorine (C—F) bonds. Examples of fluorine-containing drugs are the anticancer drug Fluoracil (C
4
H
3
FN
2
O
2
, 5-fluorouracil), antidepressant drug Prozac® (C
17
H
18
F
3
NO, fluoroxetine) and painkiller Dalmane (C
21
H
23
CIFN
3
O, flurazepam). Perflubron (C
8
F
17
Br, bromoperfluorooctane) is an oxygencarrier in a formulation now undergoing clinical trials as a blood substitute. Many agricultural chemicals and pesticides also contain carbon-fluorine bonds.
Chemical analysis for drugs can be done by isolating the drug and then measuring concentrations of compounds. This approach can be expensive. Alternatively, known chemical compounds can be labeled with radioactive elements to form tracers. The radioactive compounds and their metabolites can be followed in the body or tissues by observing emitted radioactivity. However, making and disposing of radiolabeled compounds is also expensive. These expenses can be found in many drug development programs.
Accordingly, the inventors have determined that it would be useful to accurately and inexpensively identify fluoroorganic compounds. The present invention provides a method and apparatus for achieving this object.
SUMMARY OF THE INVENTION
The invention is directed to an apparatus and method for detecting the presence of compounds having carbon-halogen bonds using Raman spectroscopy. The method detects any carbon-halogen bond, and is particularly useful in detecting carbon-fluorine bonds.
In one aspect, the method uses pulsed laser Raman spectroscopy to detect carbon-halogen bonds, using an effect of inelastic scattering of light. A sample is irradiated from a noncontinuous periodic pulse light source, such as a metal-vapor laser. Raman scattered light emitted from the sample is then detected to determine if a characteristic Raman scattered light spectrum for a compound having a carbon-halogen is present in the sample.
In another aspect, the apparatus for Raman spectroscopy includes a noncontinuous periodic pulse metal vapor laser and a monochromator for visible and ultraviolet light. The apparatus also includes a detector for detecting the emitted Raman scattered light and a pulse recording system to eliminate primary fluorescence associated with the sample.
In yet another aspect, the invention is directed to a method for detecting a fluoroorganic compound that includes exposing a sample to an excitation light source and measuring a frequency of an acoustic mode of the compound. The method also includes measuring a frequency of an optical mode of the compound and detecting a shift in the optical and acoustic mode frequencies. The molecular length of the compound is approximated as a function of the shift in frequencies to determine the presence of the fluoroorganic compound.
The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.
REFERENCES:
patent: 3906241 (1975-09-01), Thompson
patent: 5444528 (1995-08-01), Puschell
patent: 5646425 (1997-07-01), Beach
Laloraya, K., et al., “Laser excited Raman spectrum of 1,1,1-trifluoro-2,2,2-tricloroethane.” J. Chem. Phys. vol. 61, No. 5, pp. 1918-1922 (Sep. 1, 1974).
Craig, N., et al., “Vibrational Assignments and Potential Constants for cis- and trans-1,2-Difluoroethylenes and Their Deuterated Modifications.” J. Chem. Phys., vol. 51, No. 3, pp. 1127-1142 (Aug. 1, 1969).
Mann, D., et al., “Vibrational Spectrum of Fluorotrichloroethylene.” J. Chem. Phys., vol. 23, No. 11, pp. 1989-1993 (Nov. 1955).
Mann, D., et al., “Infrared and Raman Spectra of Trans-Difluorodichloroethylene.” J. Chem. Phys., vol. 26, No. 4, pp. 773-779 (Apr. 1957).
Nielsen, J., et al., “Infrared and Raman Spectra of Fluorinated Ethylenes. VI. Fluorotrichloroethylene.” J. Chem. Phys., vol. 23, No. 11, pp. 1994-1996 (Nov. 1955).
Nielsen, J., et al., “Raman Spectrum of Gaseous 1-Fluoro-chloroethylene.” J. Chem. Phys., vol. 26, No. 6, pp. 1566-1567 (Jun. 1957).
Korppi-Tommola, J., et al., “The Gas Phase Raman Band Contours of 1,3,5-Trifluorobenzene and the Infrared and Raman Band Contours of 1,3,5-Trifluorobenzene-d31,2.” J. Mol. Spectro., vol. 87, pp. 382-392 (1981).
Da Costa, A., et al., “Raman Spectra and Structure of Perfluorodecanoic Acid and Perfluorodecanoates.” Rev. Port. Quim., vol. 26, pp. 154-162 (1984).
Blick, K., et al., “Vibrational spectrum and frequency assignments for 2,2-diaminohexafluoropropane.” Spectro. Acta., vol. 27A, pp. 777-782 (1971).
Shurvell, H., et al., “The infrared and Raman spectra of pentafluorobenzonitrile.” Spectro. acta., vol. 24A, pp. 1257-1266 (1968).
Crowder, G., et al., “Infrared and Raman spectra of methyl trifluoroacetate.” Spectro. acta., vol. 27A, pp. 1873-1877 (1971).
Berney, C., “Spectroscopy of CF2COZ compounds—IV Vibrational spectrum of trifluoroacetyl fluoride.” Spectro. Acta., vol. 27A, pp. 663-672 (1971).
Miller, F., et al., “The infrared and Raman spectra of hexafluoro-, hexachloro- and hexabromocyclopropane.” Spectro. Acta., vol. 23A, pp. 1609-1618 (1967).
Bailey, R., et al., “The vibrational spectra of perfluorotoluene.” Spectro. Acta., vol. 24A, pp. 1891-1898 (1968).
Murto, J., et al., “Fluoroalcohols—XX. Infrared and Raman spectra of hexafluoro-2-propanol and its deuterated analogues.” Spectro. Acta., vol. 29A, pp. 1121-1137 (1973).
Augdahl, E., et al., “The vibrational spectra of 1-halo-3,3,3-trifluoropropynes.” Spectro. Acta., vol. 29A, pp. 1329-1338 (1973).
Dawson, J., et al., Infrared spectra of tris(fluoroalkyl)-s-triazines. Spectro. Acta., vol. 23A, pp. 1211-1220 (1966).
Kinumaki, S., et al., “Low Frequency Bands and Barrier to Internal Rotation in Pentafluoroethane.” Bull. Chem. Soc. Japan, vol. 41, pp. 809-813 (1968).
Zimmerman, R., et al., “The Vapor-Phase Infrared and Raman Spectra of p-Difluorobenzene (h4) and (d4).” J. Mol. Spectro., vol. 110, pp. 312-325 (1985).
Nielsen, J., et al., “Infrared and Raman Spectra of Fluorinated Ethanes Part XVIII. 1,1,1,2-Tetrafluoroethane.” J. Mol. Spectro., vol. 17, pp. 341-347 (1965).
Lunelli, B., et al., “Out-of-Plane Vibrations of 1,2-Difluorobenzene and 1,2-Difluorobenzene-d4.” J. Mol. Spectro., vol. 104, pp. 203-207 (1984).
Lunelli, B., et al. “The Vibrational Spectrum of 1,2-Difluorobenzene and 1,2-Difluorobenzene-d4.” J. Mol. Spectro., vol. 64, pp. 1-14 (1977).
Zwarich, R., et al., “The Vibrational Spectra of 9-Fluorenone.” J. Mol. Spectro., vol. 51, pp. 38-49 (1974).
Kinumaki, S., et al., “Low Frequency Bands and Barrier to Internal Rotation in Pentafluoroethane,” Bulletin of the Chemical Society of Japan, vol. 41, pp. 809-813 (1968).
Tuazon, E.C., et al., “Vibrational Spectra of Gaseous 1,1,1-Trifluoro-2-butyne,” The Journal of Chemical Physics, vol. 53, No. 8, pp. 3178-3187 (Oct. 15, 1970).
Harris, W.C., et al, “Interpretation of the vibrational spectral of small ring systems II. Perfluorocyclobutane,” The Journal of Chemical Physics, vol. 60, No. 11, pp. 4175-4180 (Jun. 1, 1974).
El Bermani, M.F., et al., “Rotation Isomers of the 1-Fluoro-2-haloethanes,” The Journal of Chemical Physics, vol. 49, No. 1, pp. 340-346 (Jul. 1, 1968).
Koenig, J.L., et al., “Raman Scattering and Band Assignments in Polytetrafluoroethylene,” The Journal of Chemical Physics, vol. 50, No. 7, pp. 2823-2829 (Apr. 1, 1969).
Craig, N.C., et al., Vibrationalo Spectra and Assignments for cis- and trans-1,2-Difluorocyclopropane and Three Deuterium Substituted Modification of Each Isomer, The Journal of Physical Chemistry, vol. 79, No. 21, pp. 2270-2282 (1975).
Cra
Gorelik Vladimir Semenovich
Sharts Clay Marcus
Sharts Olga
Evans F. L.
Fish & Richardson P.C.
San Diego State University
Sharts Olga
LandOfFree
Method and apparatus for determination of carbon-halogen... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for determination of carbon-halogen..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for determination of carbon-halogen... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2561259