US3907646A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Measurement of gas production of microorganisms
Assignee: National Aeronautics and Space Administration
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Filing: 1974-07-24
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Granted: 1975-09-23
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Expires: 1994-07-24
Abstract
Abstract A simple apparatus and method is disclosed for measuring gas production by microorganisms using a pressure transducer to sense pressure buildup by members of the Enterobacteriaceae group of bacteria. The test system consists of a 5.0 psid pressure transducer and a pressure equalizer valve attached to the metal cap of a 20 X 150 mm test tube with gas pressure being recorded on a strip-chart recorder.
Inventors
- 👤 Judd R Wilkins
- 👤 Albin O Pearson
- 👤 Stacey M Mills
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 01:33
CPC Classifications
C; C12; C12Q; C12Q1/00; C12Q1/02; C12Q1/04; G; G01; G01N; G01N7/00; G01N7/14; C12Q2304/00; C12Q2304/40; Y; Y10; Y10S; Y10S435/00; Y10S435/802; Y10S435/807; Y10S435/8215; Y10S435/822; Y10S435/848; Y10S435/849
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
97 words
A METHOD OF QUANTIFYING THE NUMBER OF GAS-PRODUCING MICROORGANISMS IN A LIQUID SAMPLE COMPRISING DILUTING A SPECIFIC QUANTITY OF A LIQUID SAMPLE BELIEVED TO CONTAIN GAS-PRODUCING MICROORGANISMS IN A BROTH KNOWN TO PERMIT GROWTH OF GAS-PRODUCING MICROORGANISMS, INCUBATING THE DILUTED SAMPLE UNDER TEMPERATURE AND PRESSURE CONDITIONS KNOWN TO STIMULATE GAS-PRODUCING MICROORGANISM GROWTH, FOR A SPECIFIC PERIOD OF TIME, MEASURING THE GAS PRESSURE PRODUCED BY THE INCUBATED SAMPLE OVER AN ESTENDED PERIOD OF TIME IN TERMS OF AN ELECTRICAL SIGNAL, RECORDING A PLOT OF THE ELECTRICAL SIGNAL PRODUCED BY THE GAS PRESSURE OVER AN EXTENDED PERIOD OF TIME,
Claim 2
Independent Claim
97 words
A METHOD OF QUANTIFYING THE NUMBER OF GAS-PRODUCING MICROORGANISMS IN A LIQUID SAMPLE COMPRISING DILUTING A SPECIFIC QUANTITY OF A LIQUID SAMPLE BELIEVED TO CONTAIN GAS-PRODUCING MICROORGANISMS IN A BROTH KNOWN TO PERMIT GROWTH OF GAS-PRODUCING MICROORGANISMS, INCUBATING THE DILUTED SAMPLE UNDER TEMPERATURE AND PRESSURE CONDITIONS KNOWN TO STIMULATE GAS-PRODUCING MICROORGANISM GROWTH, FOR A SPECIFIC PERIOD OF TIME, MEASURING THE GAS PRESSURE PRODUCED BY THE INCUBATED SAMPLE OVER AN ESTENDED PERIOD OF TIME IN TERMS OF AN ELECTRICAL SIGNAL, RECORDING A PLOT OF THE ELECTRICAL SIGNAL PRODUCED BY THE GAS PRESSURE OVER AN EXTENDED PERIOD OF TIME,
Claim 3
Dependent Claim
17 words
The method of claim 1 wherein the gas-producing mircoorganisms are from the group consisting of the Enterobacteriaceae.
Claim 4
Dependent Claim
17 words
The method of claim 1 including the step of agitating the liquid sample during the incubation period.
Claim 5
Dependent Claim
47 words
The method of claim 1 wherein the broth known to permit growth of gas-producing microorganisms is selected from the group consisting of Lauryl tryptose broth, Eijkman lactose medium, Pheral red broth base with 0.5% lactose, phenyl red broth base with 1% glucose and Brilliant green bile broth.
Claim 6
Dependent Claim
19 words
The method of claim 1 wherein the incubation step is conducted at 35*C. for a period of 24 hours.
Claim 7
Independent Claim
108 words
A method of rapidly detecting the presence of gas-producing microorganisms in a suspect sample comprising the steps of: adding the suspect sample to a closed container having a specific quAntity of a broth known to stimulate microorganism growth, incubating the closed container under controlled time and temperature conditions known to promote microorganism growth, constantly measuring any increase in gas pressure within the closed container during incubation, converting the gas pressure measurements into a continuous electrical signal; and recording a plot of the electrical signal in terms of gas pressure produced with the recorded plot being indicative of the presence and quantity of microorganism within the sample being tested.
Claim 8
Independent Claim
108 words
A method of rapidly detecting the presence of gas-producing microorganisms in a suspect sample comprising the steps of: adding the suspect sample to a closed container having a specific quAntity of a broth known to stimulate microorganism growth, incubating the closed container under controlled time and temperature conditions known to promote microorganism growth, constantly measuring any increase in gas pressure within the closed container during incubation, converting the gas pressure measurements into a continuous electrical signal; and recording a plot of the electrical signal in terms of gas pressure produced with the recorded plot being indicative of the presence and quantity of microorganism within the sample being tested.
References Cited (Backward Citations)
US3743581A
Cited
US3743581B1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-22 | 1979-03-24 | 1979-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-22 | 1983-03-24 | 1983-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-22 | 1987-03-24 | 1987-09-23 | $7700.00 | Window Closed / Lapsed |