US4245043A
Expired / Lapsed
US
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Negative control media device and method for microbiologic biochemical tests
Assignee: 3M Co
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Filing: 1979-06-29
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Granted: 1981-01-13
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Expires: 1999-06-29
Abstract
Abstract A microorganism identification test container comprises a tray member provided with a plurality of integrally formed open wells. A number of the wells are microorganism identification test wells having biochemical test media which in hydrated form permits growth of microorganisms with the generation of a volatile color-forming compound. Another number of wells are negative control wells corresponding to each of the test wells provided and including an inhibitor which in aqueous solution prevents color formation in the negative control wells from the volatile color-forming compound generated in the test wells. The wells are preferably disposed in a number of generally parallel rows or lines wherein one line or row contains a series of biochemical test media and an adjacent line or row contains the corresponding negative control medium for each test. Biochemical test media used in the identification of microorganisms either contain an indicator or generate an indicator upon inoculation with microorganism, that responds to specific microorganism activity with a detectable change in color. Comparison between the negative control wells and the test wells, after inoculation and incubation of the microorganism, indicates the presence of a particular microorganism. Since many of the biochemical test media employ indicators that produce only subtle visually detectable changes in response to microorganism activity, the appearance of the negative control must remain essentially unchanged or subtle changes in the biochemical test wells will be difficult to perceive.
Inventors
- 👤 Maryls E. Lund
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 07:34
CPC Classifications
C; C12; C12Q; C12Q1/00; C12Q1/02; C12Q1/18; C12Q1/20; B; B01; B01L; B01L3/00; B01L3/50; B01L3/508; B01L3/5085; C12M; C12M23/00; C12M23/02; C12M23/12; C12M41/00; C12M41/30; C12M41/36; B01L2200/00; B01L2200/16; B01L2300/00; B01L2300/08; B01L2300/0809; B01L2300/0829
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
123 words
A device for use in the identification of microorganisms, comprising a unitary tray member having a plurality of integrally formed test wells, at least some of said wells serving as identification test wells for microorganisms and containing biochemical test media which in hydrated form permits growth of said microorganisms with the generation of a volatile color-forming compound, and corresponding negative control wells in close proximity to each of said test wells, said negative control wells containing negative control media including an inhibitor which in aqueous solution prevents color formation otherwise occuring therein from said volatile color forming compound, and wherein both said biochemical test media prior to inoculation with said microorganisms and said negative control media have the same color in hydrated form.
Claim 2
Independent Claim
123 words
A device for use in the identification of microorganisms, comprising a unitary tray member having a plurality of integrally formed test wells, at least some of said wells serving as identification test wells for microorganisms and containing biochemical test media which in hydrated form permits growth of said microorganisms with the generation of a volatile color-forming compound, and corresponding negative control wells in close proximity to each of said test wells, said negative control wells containing negative control media including an inhibitor which in aqueous solution prevents color formation otherwise occuring therein from said volatile color forming compound, and wherein both said biochemical test media prior to inoculation with said microorganisms and said negative control media have the same color in hydrated form.
Claim 3
Dependent Claim
12 words
The device according to claim 1 wherein said inhibitor is a buffer.
Claim 4
Dependent Claim
35 words
A device according to claim 2 wherein said microorganism identification test wells contain said biochemical test media selected from the group consisting of phosphodiesterase medium, Voges-Proskauer medium, o-nitrophenyl-β-D-galactopyranoside medium, tryptophan deaminase medium and indol medium.
Claim 5
Dependent Claim
25 words
The device according to claim 3 wherein said buffer is selected from the group consisting of KH 2 PO 4 , and NaOH plus glycine.
Claim 6
Dependent Claim
32 words
The device according to claim 4 wherein at least one of said negative control wells contains phosphodiesterase negative control medium which comprises peptone buffered to a pH of about 4.8 to 5.3.
Claim 7
Dependent Claim
34 words
The device according to claim 4 wherein at least one of said negative control wells contain o-nitrophenyl-β-D-galactopyranoside negative control medium which comprises o-nitrophenyl-β-D-galactopyranoside and peptone buffered at a pH of about 4.8 to 5.3.
Claim 8
Dependent Claim
39 words
The device according to claim 4 wherein at least one of said negative control wells contains Voges-Proskauer negative control medium which comprises methyl red Voges Proskauer medium and creatine monohydate buffered to a pH of about 5.6 to 6.0.
Claim 9
Dependent Claim
35 words
The device according to claim 4 wherein at least one of said negative control wells contains tryptophan deaminase negative control medium which comprises tryptone, L-tryptophan, and NaCl to a pH of about 4.3 to 5.2.
Claim 10
Dependent Claim
34 words
The device according to claim 4 wherein at least one of said negative control wells contains indol negative control medium which comprises tryptone and NaCl buffered to a pH of about 9.8 to 10.2.
Claim 11
Dependent Claim
54 words
A device according to claim 1 wherein each of said microorganism identification test wells contains a different biochemical test media, the color of which after inoculation with said microorganisms can be compared with the color of said media in said corresponding negative control wells to provide indicia for the accurate identification of said microorganisms.
Claim 12
Dependent Claim
24 words
A device according to claim 1 wherein said biochemical test media and said negative control media are present in said wells in dried form.
Claim 13
Dependent Claim
35 words
A device according to claim 1 wherein at least some of said wells serve as antibiotic test wells containing a predetermined concentration of an antibiotic, and antibiotic control wells, said control wells containing no antibiotic.
Claim 14
Dependent Claim
23 words
A device according to claim 12 wherein said biochemical test media, said negative control media and said antibiotic are present in dried form.
Claim 15
Dependent Claim
18 words
A device according to claim 12 wherein said wells are disposed in a number of generally parallel rows.
Claim 16
Dependent Claim
93 words
The device of claim 14 wherein: (a) said antiobiotic test wells are disposed in several vertical rows, each of said vertical rows containing a different antibiotic with a different concentration of said antibiotic present in each of said test wells of said row; and (b) said microorganism identification test wells and said negative control wells are disposed in pairs as horizontal lines of wells running perpendicular to said vertical rows of antibiotic test wells with each horizontal line of negative control wells lying adjacent to a horizontal line of said microorganism identification wells.
Claim 17
Dependent Claim
102 words
The device of claim 15 wherein: (a) said vertical rows of antibiotic test wells number sixteen, each vertical row having seven antibiotic test wells, constituting seven horizontal lines of wells; and (b) said pairs of horizontal lines of test wells and negative control wells number two with one of said pair of horizontal lines of rows running perpendicular and above said vertical antibiotic test rows and the other of said pairs running perpendicular and below said vertical antibiotic test rows; with said horizontal lines of rows of microorganism test wells and negative control wells constituting sixteen wells in each of said lines.
Claim 18
Independent Claim
191 words
A method for the identification of microorganisms comprising: (a) providing a unitary tray member having a plurality of integrally formed test wells, at least some said wells serving as microorganism identification test wells containing, in dried form, biochemical test media which in hydrated form permits growth of said microorganisms with the generation of a volatile color-forming compound and corresponding negative control wells in close proximity to each of said test wells, said negative control wells containing, in dried form, negative control media including a buffer which in aqueous solution prevents color formation therein from said volatile color forming compound, and wherein both said biochemical test media prior to inoculation with said microorganisms and said negative control media have the same color when in hydrated form; (b) reconstituting the contents of said identification test wells and said negative control wells with water; (c) inoculating said identification test wells with said microorganism; (d) incubating said tray member; and (e) comparing said identification test wells with said negative control wells to determine whether there has been a detectable change in said biochemical test media in said identification test wells, indicating activity of said microorganism.
Claim 19
Independent Claim
191 words
A method for the identification of microorganisms comprising: (a) providing a unitary tray member having a plurality of integrally formed test wells, at least some said wells serving as microorganism identification test wells containing, in dried form, biochemical test media which in hydrated form permits growth of said microorganisms with the generation of a volatile color-forming compound and corresponding negative control wells in close proximity to each of said test wells, said negative control wells containing, in dried form, negative control media including a buffer which in aqueous solution prevents color formation therein from said volatile color forming compound, and wherein both said biochemical test media prior to inoculation with said microorganisms and said negative control media have the same color when in hydrated form; (b) reconstituting the contents of said identification test wells and said negative control wells with water; (c) inoculating said identification test wells with said microorganism; (d) incubating said tray member; and (e) comparing said identification test wells with said negative control wells to determine whether there has been a detectable change in said biochemical test media in said identification test wells, indicating activity of said microorganism.
Claim 20
Dependent Claim
42 words
A method for the identification of microorganisms according to claim 17 wherein an indicator capable of producing a color change in said biochemical test media, in response to microorganism growth, is added to said biochemical test media after inoculation with said microorganism.
Claim 21
Dependent Claim
106 words
The method of claim 17 including: (a) providing some of said wells to serve as antibiotic test wells, containing in dried form, a predetermined concentration of an antibiotic, and antibiotic control wells containing no antibiotic; (b) reconstituting the contents of said antibiotic test wells and said antibiotic control wells with a nutrient broth; (c) inoculating said antibiotic test wells and said antibiotic control wells with said microorganism; (d) incubating said antibiotic test wells and said antibiotic control wells; (e) visually comparing said antibiotic test wells with said antibiotic control wells; and (f) determining the minimum concentration of antibiotic necessary to inhibit the growth of said microorganism.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-01-13 | 1984-07-14 | 1985-01-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-13 | 1988-07-14 | 1989-01-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-13 | 1992-07-14 | 1993-01-13 | $7700.00 | Window Closed / Lapsed |