US3847482A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for detecting a change in turbidity of a solution
Assignee: Bio Data Corp
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Filing: 1972-07-10
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Granted: 1974-11-12
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Expires: 1992-07-10
Abstract
Abstract A method and apparatus for detecting a change or a predetermined amount of change in the turbidity of a solution is disclosed. An important application of the method and apparatus of the present invention is in a rapid screening for the presence of Hemoglobin S in the blood. The blood may be combined with a reagent which causes any Hemoglobin S to become more insoluable producing turbidity in the resultant blood-reagent solution. The bloodreagent solution is mounted between the light source and a transducer. The output of the transducer is fed to a means for integrating the variations in the output signal of the transducer over a predetermined time interval. At the end of the predetermined time interval, an indication is given as to whether or not the integrated signal has exceeded a predetermined value. This indication may represent a predetermined change in the turbidity of the solution and also indicate whether blood being tested contains Hemoglobin S.
Inventors
- 👤 M Sokol
- 👤 F Kent
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:06
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/25; G01N21/27; G01N21/272; G01N21/47; G01N21/49; G01N21/51
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
194 words
Apparatus for testing blood for the presence of Hemoglobin S, comprising: means for receiving a substantially transparent container for holding a predetermined quantity of blood combined with a reagent which produces turbidity in the blood-reagent solution; a light source; transducer means, said transducer means producing an output signal responsive to light impingent thereon, said transparent container receiving means being mounted between said light source and said transducer means; means for passing only variations in the output signal of said transducer means to produce an optical density variation signal; means for integrating said optical density variation signal to produce a level signal; threshold detector means for detecting when said level signal exceeds a predetermined value and producing an output signal; timing means for generating a timing signal a predetermined time after initiation of the test; gating means for gating the output signal of said threshold detector in response to said timing signal; and indicating means responsive to the output of said gating means for indicating whether or not said threshold detector means detected a level signal of said predetermined value corresponding to the absence or probable presence of Hemoglobin S in the blood being tested.
Claim 2
Dependent Claim
194 words
Apparatus for testing blood for the presence of Hemoglobin S, comprising: means for receiving a substantially transparent container for holding a predetermined quantity of blood combined with a reagent which produces turbidity in the blood-reagent solution; a light source; transducer means, said transducer means producing an output signal responsive to light impingent thereon, said transparent container receiving means being mounted between said light source and said transducer means; means for passing only variations in the output signal of said transducer means to produce an optical density variation signal; means for integrating said optical density variation signal to produce a level signal; threshold detector means for detecting when said level signal exceeds a predetermined value and producing an output signal; timing means for generating a timing signal a predetermined time after initiation of the test; gating means for gating the output signal of said threshold detector in response to said timing signal; and indicating means responsive to the output of said gating means for indicating whether or not said threshold detector means detected a level signal of said predetermined value corresponding to the absence or probable presence of Hemoglobin S in the blood being tested.
Claim 3
Dependent Claim
14 words
Apparatus in accordance with claim 1 wherein said receiving means is removable for cleaning.
Claim 4
Dependent Claim
32 words
Apparatus in accordance with claim 1 wherein said substantially transparent container is a test tube having an inner diameter of approximately 5.8 to 6 millimeters and a length of approximately 70 millimeters.
Claim 5
Dependent Claim
38 words
Apparatus in accordance with claim 1 wherein said reagent is a solution including a high ionic concentration buffer solution, a reducing agent and an erythrocytic hemolyzing agent in which Hemoglobin S in its reduced form is substantially insoluble.
Claim 6
Dependent Claim
14 words
Apparatus in accordance with claim 1 wherein said transducer means includes a photoelectric cell.
Claim 7
Dependent Claim
32 words
Apparatus in accordance with claim 1 wherein said means for passing only variations in the output signal of said transducer means includes an amplifier having a capacitor in series with its input.
Claim 8
Dependent Claim
25 words
Apparatus in accordance with claim 1 wherein said integrating means includes a capacitor and a variable resistor for adjusting the integrating rate of said capacitor.
Claim 9
Dependent Claim
16 words
Apparatus in accordance with claim 1 wherein said threshold detector means comprises a Schmitt trigger circuit.
Claim 10
Dependent Claim
34 words
Apparatus in accordance with claim 1 wherein said timing means includes a microswitch for initiating operation of said timing means, said microswitch being operated by the insertion of the container into said receiving means.
Claim 11
Dependent Claim
27 words
Apparatus in accordance with claim 1 wherein said timing means generates a timing signal upon said threshold detector means detecting said level signal of said predetermined value.
Claim 12
Dependent Claim
62 words
Apparatus in accordance with claim 1 wherein said gating means includes a bistable circuit, said bistable circuit having a first and a second output and being set in response to the output signal of said threshold detector means, and a pair of AND gates, each of said AND gates receiving as inputs an output from said bistable circuit and the timing signal.
Claim 13
Dependent Claim
17 words
Apparatus in accordance with claim 1 wherein said indicator means includes a first and a second lamp.
Claim 14
Dependent Claim
17 words
Apparatus in accordance with claim 12 wherein said indicator means includes means for producing an audible signal.
References Cited (Backward Citations)
US3492095A
Cited
US3725204A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-11-11 | 1978-05-13 | 1978-11-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-11 | 1982-05-13 | 1982-11-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-11 | 1986-05-13 | 1986-11-12 | $7700.00 | Window Closed / Lapsed |