EP0597584A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method and apparatus for detecting biological activities in a specimen
Assignee: Becton Dickinson and Co
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Filing: 1993-10-04
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Granted: —
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Expires: 2013-10-04
Abstract
Abstract The present invention disclosure describes a pressure/vacuum method and instrument for detecting biological activities in blood culture vials, that is non-invasive, does not require chemical sensors, does not require high-brightness short-wavelength light sources, is safe against eventual extreme high pressure values, and is head-space-temperature compensated. A culture medium and blood specimen (34) are introduced into a sealable glass vial (48). The normally incompressible fluid suspension is made compressible through the use of a partially inflated gas bag (38) submerged within the medium. The changes in fluid position that result from bacterial growth related pressure changes within the vial head space are measured to detect biological activities.
Inventors
- 👤 Klaus W. Berndt
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 11:20
CPC Classifications
C; C12; C12Q; C12Q1/00; C12Q1/02; C12Q1/04; C12M; C12M41/00; C12M41/30; C12M41/36; C12M41/40; C12M41/46; G; G01; G01N; G01N7/00; G01N7/14; G01N7/18; G01N7/20; Y; Y10; Y10S; Y10S435/00; Y10S435/807; Y10S435/808
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
65 words
An instrument for detecting microorganisms in fluid samples, comprising: at least one sealable container with fluid medium and a gaseous head space above a fluid-gas interface, with said container adapted to sustain the growth of microorganisms; at least one compressible means submerged in said medium; measuring means to determine the amount of fluid movement resulting from microorganism growth related pressure changes within said head space.
Claim 2
Dependent Claim
20 words
An instrument as recited in claim 1, wherein said measuring means is used to determine the change in fluid level.
Claim 3
Dependent Claim
19 words
An instrument as recited in claim 1, wherein said compressible means comprises at least one partially filled gas bag.
Claim 4
Dependent Claim
48 words
An instrument as recited in claim 3, wherein said container comprises a glass tube with a lower flange and an upper flange, said lower flange being sealed with a first septum which has said gas bag secured thereto and said upper flange being sealed with a second septum.
Claim 5
Dependent Claim
25 words
An instrument as recited in claim 1, wherein the density of said compressible means is substantially equal to the density of said gaseous head space.
Claim 6
Dependent Claim
80 words
An instrument as recited in claim 2, wherein said measuring means comprises an optical level monitoring system which includes a light source and a photodetector with an area for receiving light produced by said light source, with said container, said light source and said photodetector arranged so that if the level of said medium changes, the percentage of said light from said light source imaged onto said area of said photodetector also changes, affecting an output signal from said photodetector.
Claim 7
Dependent Claim
36 words
An instrument as recited in claim 6, wherein a float is disposed at said fluid-gas interface, with said light source and said photodetector positioned so that said light from said light source intersects a float edge.
Claim 8
Dependent Claim
53 words
An instrument as recited in claim 6, wherein said light source includes a plurality of horizontally oriented filaments spaced from on another, an instrument control device being used to selectively activate said filaments until one of said filaments results in said output signal of said photodetector being approximately half of its maximum value.
Claim 9
Dependent Claim
49 words
An instrument as recited in claim 6, wherein said photodetector comprises two vertical segments, each of said segments covered with a transmission mask and having a plurality of grating-like elements, said elements of one of said segments being displaced relative to said elements of the other of said segments.
Claim 10
Dependent Claim
40 words
An instrument as recited in claim 9, wherein said elements are uniformly spaced, and said elements of said one of said segments are displaced relative to said elements of said other of said structures by one-half of a grating constant.
References Cited (Backward Citations)
US2736190A
Cited
CH380414A
Cited
DE2362158B1
Cited
US4270381A
Cited
US5051360A
Cited
FR2672995A1
Cited
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