CA1125050A
Expired / Lapsed
CA
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Apparatus and method for detecting platelets in a whole blood
Assignee: Ortho Clinical Diagnostics Inc
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Filing: 1979-09-04
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Granted: 1982-06-08
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Expires: 1999-09-04
Abstract
Abstract Abstract Apparatus and Method For Detecting Platelets In Whole Blood A diluted whole blood sample is hydrodynamically focused to a given point. A light beam is transversely focused on the same point and the principles of dark field microscopy are utilized, detecting scattered light and thereby discriminating platelets from red blood cells based on cell volume and refractivity.
Inventors
- 👤 William P. Hansen, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
CA
Data Source
google_patents
Last Synchronized
2026-11-02 11:54
CPC Classifications
G; G01; G01N; G01N15/00; G01N15/02; G01N15/0205
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
49 words
A method of analyzing blood cells of a sample comprising: a) providing all cells to be analyzed in a single sample stream analysis; b) illuminating respective blood cells in said sample; and c) discriminating platelets from red blood cells based on the parameters of cell volume and cell refractivity.
Claim 2
Independent Claim
49 words
A method of analyzing blood cells of a sample comprising: a) providing all cells to be analyzed in a single sample stream analysis; b) illuminating respective blood cells in said sample; and c) discriminating platelets from red blood cells based on the parameters of cell volume and cell refractivity.
Claim 3
Dependent Claim
61 words
The method of claim 1 wherein said illuminating step comprises: a) passing the cells, one at a time, past a predetermined focal point; b) providing a regulated source of visible light; c) focusing light from said source substantially normally to cell flow to illuminate substantially single cells at said point, said focused light beam having a predetermined cross-section at said point.
Claim 4
Dependent Claim
48 words
A method as described in claim 1 wherein said illuminating step comprises focusing light normally to a sensing zone through which cells of said sample pass, in sequence, generally normally to incident light, said zone being elongated generally normally both to incident light and to the sample stream.
Claim 5
Independent Claim
54 words
The method of claims 1 or 3 wherein said discri-minating step comprises: a) detecting substantially low angle, forward scattered light from cells; b) blocking substantially all the light from said cells; c) discriminating whether a red cell or a platelet scattered the detected light, based on the amplitude and duration of light so detected.
Claim 6
Dependent Claim
35 words
The method of claim 4 wherein said blocking step comprises placing a physical block across the light path emergent from said cells, said block being placed in the focal plane eventuating from said illuminating step.
Claim 7
Dependent Claim
24 words
The method of claim 5 wherein said detecting step comprises detecting light emergent from said focal point and not blocked in said placing step.
Claim 8
Dependent Claim
55 words
A method as provided in claim 1 which further comprises: a) providing focused illumination of individual cells in the sample; b) discriminating light scattered by platelets from light scattered by red cells by applying scattered light to a dark field optics system whereby platelets are discriminated from red blood cells in a whole blood sample.
Claim 9
Dependent Claim
103 words
Apparatus for discrimination of platelets from red blood cells in a whole blood sample comprising: a) means for providing a hydrodynamically focused fluid stream of said sample, to a focus region dimensionally accommodating all classes of cell under investigation; b) means for illuminating said focus region, transversely to the cell flow path; c) means for detecting light scattered from cells at said focus region, exclusively of light transmitted through said focus region; and d) means for developing a signal corresponding to detected scattered light, said signal defining respective peaks corresponding to the physical dimensions and refrac-tivity characteristics of respective cells in said samples.
Claim 10
Dependent Claim
103 words
Apparatus for discrimination of platelets from red blood cells in a whole blood sample comprising: a) means for providing a hydrodynamically focused fluid stream of said sample, to a focus region dimensionally accommodating all classes of cell under investigation; b) means for illuminating said focus region, transversely to the cell flow path; c) means for detecting light scattered from cells at said focus region, exclusively of light transmitted through said focus region; and d) means for developing a signal corresponding to detected scattered light, said signal defining respective peaks corresponding to the physical dimensions and refrac-tivity characteristics of respective cells in said samples.
Claim 11
Dependent Claim
76 words
Apparatus as described in claim 8 wherein said means for illuminating comprises a source of light, and means for focusing said light, along an axis, onto said focus region, the focused beam at said region having pre-determined cross-sectional dimensions designated a and b: and wherein said means for detecting includes a contrived obstacle, on said axis, for providing a blockage of light emergent from said region and which was transmitted through said region a x b.
References Cited (Backward Citations)
No citation records indexed.
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