US4298347A
Expired / Lapsed
US
⏱️ 0.0 years remaining
13 CO2 Breath test
Assignee: Tracer Technologies Inc
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Filing: 1980-02-25
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Granted: 1981-11-03
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Expires: 2000-02-25
Abstract
Abstract A method for the analysis of exhaled carbon dioxide for clinical diagnostic application which contains a mixture of 13CO2 and 12CO2 is disclosed. The method includes the use of a solution which absorbs the carbon dioxide from the exhaled air, reacts with the carbon dioxide to form a ketone and uses the height of the unique infrared spectral peaks in the carbonyl frequency range to quantitate the 13CO2 and the 12CO2 components of the exhaled air.
Inventors
- 👤 Fraser M. Walsh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:47
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/08; A61B5/0813; G; G01; G01N; G01N33/00; G01N33/48; G01N33/483; G01N33/497; G01N33/50; G01N33/84; Y; Y10; Y10T; Y10T436/00; Y10T436/20; Y10T436/204998
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
86 words
A method for the analysis of mass-labeled carbon dioxide in exhaled air containing a mixture of 12 CO 2 and 13 CO 2 comprising: contacting a sample of the exhaled air with a solution of an organometallic compound that reacts with CO 2 to form 13 C and 12 C labeled carbonyl compounds having unique and well separated infrared spectral peaks for the 12 C and 13 C products and determining the relative amounts of the 13 C and 12 C carbonyl compound by infrared spectroscopy.
Claim 2
Independent Claim
86 words
A method for the analysis of mass-labeled carbon dioxide in exhaled air containing a mixture of 12 CO 2 and 13 CO 2 comprising: contacting a sample of the exhaled air with a solution of an organometallic compound that reacts with CO 2 to form 13 C and 12 C labeled carbonyl compounds having unique and well separated infrared spectral peaks for the 12 C and 13 C products and determining the relative amounts of the 13 C and 12 C carbonyl compound by infrared spectroscopy.
Claim 3
Dependent Claim
28 words
The method of claim 1 wherein said organometallic compound is selected from the group consisting of phenyl lithium and phenyl magnesium halides and said carbonyl compound is benzophenone.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-11-02 | 1985-05-04 | 1985-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-02 | 1989-05-04 | 1989-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-02 | 1993-05-04 | 1993-11-03 | $7700.00 | Window Closed / Lapsed |