US4467032A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Identification and enumeration of microbial cells
Assignee: Warner Lambert Co LLC
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Filing: 1982-04-26
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Granted: 1984-08-21
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Expires: 2002-04-26
Abstract
Abstract A process and apparatus is disclosed for rapid and accurate identifying and enumerating of microorganisms. A sample believed to contain a certain microorganism is combined with an inhibiting reagent having a known specificity for the microorganism. The combined sample and inhibiting reagent is placed in an alternating current electrical field having a frequency sufficiently high to cause alignment of microbial cells in the sample. A polarized beam of laser light is then passed through the sample and the extent of birefringence is measured. The measured birefringence is compared with that of a control sample known to contain the microorganism under investigation to determine the microorganism in the sample.
Inventors
- 👤 George E. Lowke
- 👤 Robert J. Meltzer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:20
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/25; G01N21/31; G01N21/33; C; C12; C12M; C12M41/00; C12M41/30; C12M41/36; G01N21/21; G01N21/23
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
158 words
A method for identifying and enumerating microbial cells in a sample of unknown material comprising: A. isolating a quantity of said sample of unknown material; B. combining said sample with at least one inhibiting reagent having a known specificity for said microbial cells; C. placing said combined sample in an alternating current electrical field, said electrical field having a frequency sufficiently high to cause any of said microbial cells present in said sample, to move into alignment therewith; D. passing a polarized beam of laser light through said combined sample and measuring the extent of birefringence thereof; and E. comparing the birefringence of said combined sample with the birefringence of a control sample, known to contain the microbial cell under investigation, in combination with said inhibiting reagent; F. wherein said control sample is prepared and measured in accordance with Steps A-D herein, and the presence of said microbial cell in the unknown sample is determined from said comparison.
Claim 2
Independent Claim
158 words
A method for identifying and enumerating microbial cells in a sample of unknown material comprising: A. isolating a quantity of said sample of unknown material; B. combining said sample with at least one inhibiting reagent having a known specificity for said microbial cells; C. placing said combined sample in an alternating current electrical field, said electrical field having a frequency sufficiently high to cause any of said microbial cells present in said sample, to move into alignment therewith; D. passing a polarized beam of laser light through said combined sample and measuring the extent of birefringence thereof; and E. comparing the birefringence of said combined sample with the birefringence of a control sample, known to contain the microbial cell under investigation, in combination with said inhibiting reagent; F. wherein said control sample is prepared and measured in accordance with Steps A-D herein, and the presence of said microbial cell in the unknown sample is determined from said comparison.
Claim 3
Dependent Claim
23 words
The method of claim 1 wherein said sample material is disposed in a non-toxic, electrically inert liquid, prior to participation in Step B.
Claim 4
Independent Claim
25 words
The method of claims 1 or 2 wherein said sample material is eliminated of extraneous matter to reduce the retained charge and eliminate electrical interference.
Claim 5
Dependent Claim
13 words
The method of claim 3 wherein said sample material is treated by centrifugation.
Claim 6
Dependent Claim
13 words
The method of claim 3 wherein said sample material is treated by filtration.
Claim 7
Dependent Claim
27 words
The method of claim 1 wherein said inhibiting reagents comprise materials not in clinical use, that exert an effect on the cell wall of said microbial cells.
Claim 8
Dependent Claim
28 words
The method of claim 6 wherein said inhibiting reagents are selected from the group consisting of antimicrobial compounds; plant lectins; non-toxic, inert dyes; vitamin compounds; and mixtures thereof.
Claim 9
Independent Claim
26 words
The method of claims 1, 6 or 7 wherein a plurality of said samples are prepared, and each sample is combined with a different inhibiting reagent.
Claim 10
Dependent Claim
17 words
The method of claim 1 wherein said electrical field has a frequency of at least 60 Hz.
Claim 11
Dependent Claim
20 words
The method of claim 1 wherein said electrical field ranges in frequency from about 60 Hz to about 700 Hz.
Claim 12
Dependent Claim
39 words
The method of claim 1 wherein during Step D said electrical field is withdrawn, and said laser beam is maintained for a period of time sufficient to permit said cells to move out of alignment with said electrical field.
Claim 13
Dependent Claim
22 words
The method of claim 1 wherein said beam is one millimeter in width, and has a line of travel of 100 millimeters.
Claim 14
Dependent Claim
16 words
The method of claim 1 wherein the Steps thereof are performed in a continuous, atomated manner.
References Cited (Backward Citations)
US4101383A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-08-21 | 1988-02-20 | 1988-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-08-21 | 1992-02-20 | 1992-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-08-21 | 1996-02-20 | 1996-08-21 | $7700.00 | Window Closed / Lapsed |