Chemistry: analytical and immunological testing – Oxygen containing – Molecular oxygen
Patent
1986-09-11
1989-03-07
Richman, Barry S.
Chemistry: analytical and immunological testing
Oxygen containing
Molecular oxygen
128633, 128634, 128665, 128666, 2504591, 356 41, 436136, 436172, 436178, G01N 2176, G01N 3352, A61B 500
Patent
active
048106550
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
This invention relates generally to the measurement of oxygen concentration using the quenching of emission of a luminescent aromatic molecule embedded in a plastic medium.
BACKGROUND OF THE INVENTION
It is known that a luminescent aromatic molecule embedded in plastic is subject to quenching by oxygen present in the gas or liquid in contact with the plastic. This phenomenon was reported by Bergman (Nature 218:396, 1966), and a study of oxygen diffusion in plastic was reported by Shaw (Trans. Faraday Soc. 63:2181-2189, 1967). Stevens, in U.S. Pat. No. 3,612,866, ratios the luminescence intensities from luminescent materials dispersed in oxygenpermeable and oxygen-impermeable plastic films to determine oxygen concentration. Lubbers et al. in U.S. Pat. No. 4,003,707 proposed the possibility of positioning the emitting substance at the end of an optical fiber. Peterson et al. in U.S. Pat. No. 4,476,870 also employs the quenching of an emitting molecule in plastic at the end of an optical fiber. Both Lubbers and Peterson reference emission against scattered exciting light.
The quenching of the luminescence of an emitter at the end of an optical fiber has been used in temperature sensors. For temperature probes the emitters are generally solid phosphors rather than an aromatic molecule embedded in plastic, since access by molecules from the environment is not desirable. Various methods have been used to measure the amount of quenching: (i) Quick et al. in U.S. Pat. No. 4,223,226 ratios the intensity at one wavelength of the emission against another; (ii) Quick et al. also proposes determining the length of time it takes for the signal to fall from one level to another; (iii) Samulski in U.S. Pat. No. 4,245,507 (reissued as U.S. Pat. No. Re. 31,832) proposes to measure quenching by determining the phase of the emitted life. In a very recent patent for temperature sensing at the end of an optical fiber, Hirschfeld in U.S. Pat. No. 4,542,987 proposes, in addition to method (i), that (iv) emission lifetime be used to measure quenching and that (v) Raman scattered light can be used as a reference.
Eastwood and Gouterman (1970) noted generally with respect to Pd and Pt porphyrin complexes that their "relatively high [emission] yields and short triplet lifetimes . . . may make these systems useful as . . . biological probes for the presence of oxygen." More recently, Bacon and Demas in UK Patent Application No. 2,132,348A propose the use of, inter alia, porphyrin complexes of VO.sup.2+, CU.sup.2+, Pt .sup.2+, ZN.sup.2+ and Pd.sup.2+ or dimeric Rh, Pt, or Ir complexes of monitoring oxygen concentration by emission quenching of intensity or lifetime. Suitable ligands would reportedly be etioporphyrin, octaethylporphin, and porphin.
SUMMARY OF THE INVENTION
Methods and compositions are described for measuring oxygen concentration, particularly for monitoring oxygen in the blood with a fiber optic catheter. Oxygen concentration is determined by observing quenching of the emission from a luminescent (phosphorescent or fluorescent) molecule embedded in oxygen-permeable plastic. A test fluid of unknown oxygen concentration is contacted with a plastic film containing at least one luminescent substance. The film is subjected to irradiation over some period of time by light of a wavelength that is strongly absorbed by the luminescent substance, and a measure of the time dependence of luminescent emission intensity I(t) is obtained. Three modes of determining oxygen concentration from I(t) are described. (i) Subsequent to a brief (approximately 5 us) flash of light I(t.sub.i) is determined by use of a transient recorder and fit to Eq. (6). An average decay rate period of linear decay of luminescent emission is determined from the I(t) data, and that intensity versus time profile is referenced against similarly obtained profiles for reference fluids of known oxygen concentration, using slopes, intensity or time setpoints. (iii) The sample is irradiated for some time interval (generally under 50 us) u
REFERENCES:
patent: Re31832 (1985-02-01), Samulski
patent: 3429667 (1969-02-01), Hart et al.
patent: 3612866 (1971-10-01), Stevens
patent: 3725658 (1973-04-01), Stanley et al.
patent: 4003707 (1977-01-01), Lubbers et al.
patent: 4223226 (1980-09-01), Quick et al.
patent: 4245507 (1981-01-01), Samulski
patent: 4399099 (1963-08-01), Buckles
patent: 4476870 (1984-10-01), Peterson et al.
patent: 4542987 (1985-09-01), Hirschfeld
patent: 4652143 (1987-03-01), Wickersheim et al.
Spellane et al., Inorg. Chem., vol. 19, pp. 386-391, 1980.
Peterson et al., Rev. Sci. Instrum., vol. 51, No. 5, pp. 670-671, 1980, Class 436/172.
Brown, Rev. Sci. Instrum., vol. 34, No. 4, pp. 414-415, 1963, Class 250/459.1.
Stadelmann, Journal of Luminescence, vol. 3, No. 2, pp. 143-151, 1970, Class 250/459.1.
Chernyavskii et al., J. Appl. Spectrosc., vol. 13, No. 5, pp. 1471-1474, 1970, Class 250/459.1.
Aartsma et al., J. Am. Chem. Soc., vol. 104, No. 23, pp. 6278-6283, 1982.
Vogler et al., Inorganic Chimica Acta, vol. 46, pp. 101-105, 1980.
Eastwood et al., J. Mol. Spectroscopy, vol. 35, No. 3, pp. 359-375, 1970.
Callis et al., J. Mol. Spectroscopy, vol. 39, No. 3, pp. 410-420, 1971.
Gouterman et al., J. Am. Chem. Soc., vol. 97, pp. 3142-3149, 1975.
Callis et al., J. Phys. Chem., vol. 77, No. 2, pp. 154-157, 1972.
Gouterman, "Optical Spectra and Electronic Structure of Porphyrins and Related Rings", Chapter 1, pp. 1-165, in The Porphyrins, vol. III, D. Dolphin, Ed., Academic Press, N.Y., 1978.
Gouterman Martin P.
Green Edmond
Khalil Gamal-Eddin
Abbott Laboratories
Hill Jr. Robert J.
Richman Barry S.
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