US3657541A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for assaying radioactivity of a radionuclide
Assignee: EIDP Inc
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Filing: 1969-08-04
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Granted: 1972-04-18
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Expires: 1989-08-04
Abstract
Abstract This invention relates to the generation and testing of radionuclides, and more particularly, to the generation and testing of radionuclides for use in nuclear medicine.
Inventors
- 👤 Marshall E Deutsch
- 👤 Louis W Mead
- 👤 Zoltan Nagy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 00:02
CPC Classifications
G; G21; G21F; G21F5/00; G01; G01T; G01T1/00; G01T1/16; G01T1/167; G21H; G21H5/00; G21G; G21G1/00; G21G1/0005
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
292 words
The method of assaying the radioactivity of a radionuclide in a liquid which comprises the steps of 1. loading a capillary tube with a precise and predetermined quantity of said liquid and 2. positioning the capillary tube thus loaded at a prescribed distance of separation with respect to a radioactivity counting medium in a radioactivity measurement instrument, which is sensitive to the radiation emanating from said radionuclide and which has a well, said step of loading said capillary tube including a. dipping the end of said capillary tube into a sample of said liquid thereby to load said capillary tube with a precise and reproducible predetermined reduced quantity of said liquid, the step of positioning said capillary tube including: b. placing said capillary tube loaded with said liquid in a compartment section of an assay tube, said compartment section with said loaded capillary tube contained therein being secured to one end of a spacer section of said assay tube with said loaded capillary tube supported therein on a supporting surface, c. inserting said opposite end of said spacer section into said well of said measurement instrument until said spacer section engages a cooperating surface of said measurement instrument to limit the movement of the assay tube in the well to a reproducible position in which said capillary tube is reproducibly spaced said prescribed distance from said counting medium, d. taking a measure of the radioactivity of said liquid in said capillary tube by said counting medium while said assay tube is held in said position in said well, said spacer section being proportioned to hold said loaded capillary tube at said prescribed distance from said counting medium, whereby the indication of said instrument is a measure of the radioactivity of said liQuid.
Claim 2
Independent Claim
292 words
The method of assaying the radioactivity of a radionuclide in a liquid which comprises the steps of 1. loading a capillary tube with a precise and predetermined quantity of said liquid and 2. positioning the capillary tube thus loaded at a prescribed distance of separation with respect to a radioactivity counting medium in a radioactivity measurement instrument, which is sensitive to the radiation emanating from said radionuclide and which has a well, said step of loading said capillary tube including a. dipping the end of said capillary tube into a sample of said liquid thereby to load said capillary tube with a precise and reproducible predetermined reduced quantity of said liquid, the step of positioning said capillary tube including: b. placing said capillary tube loaded with said liquid in a compartment section of an assay tube, said compartment section with said loaded capillary tube contained therein being secured to one end of a spacer section of said assay tube with said loaded capillary tube supported therein on a supporting surface, c. inserting said opposite end of said spacer section into said well of said measurement instrument until said spacer section engages a cooperating surface of said measurement instrument to limit the movement of the assay tube in the well to a reproducible position in which said capillary tube is reproducibly spaced said prescribed distance from said counting medium, d. taking a measure of the radioactivity of said liquid in said capillary tube by said counting medium while said assay tube is held in said position in said well, said spacer section being proportioned to hold said loaded capillary tube at said prescribed distance from said counting medium, whereby the indication of said instrument is a measure of the radioactivity of said liQuid.
Claim 3
Dependent Claim
259 words
positioning the capillary tube thus loaded at a prescribed distance of separation with respect to a radioactivity counting medium in a radioactivity measurement instrument, which is sensitive to the radiation emanating from said radionuclide and which has a well, said step of loading said capillary tube including a. dipping the end of said capillary tube into a sample of said liquid thereby to load said capillary tube with a precise and reproducible predetermined reduced quantity of said liquid, the step of positioning said capillary tube including: b. placing said capillary tube loaded with said liquid in a compartment section of an assay tube, said compartment section with said loaded capillary tube contained therein being secured to one end of a spacer section of said assay tube with said loaded capillary tube supported therein on a supporting surface, c. inserting said opposite end of said spacer section into said well of said measurement instrument until said spacer section engages a cooperating surface of said measurement instrument to limit the movement of the assay tube in the well to a reproducible position in which said capillary tube is reproducibly spaced said prescribed distance from said counting medium, d. taking a measure of the radioactivity of said liquid in said capillary tube by said counting medium while said assay tube is held in said position in said well, said spacer section being proportioned to hold said loaded capillary tube at said prescribed distance from said counting medium, whereby the indication of said instrument is a measure of the radioactivity of said liQuid.
Claim 4
Dependent Claim
259 words
positioning the capillary tube thus loaded at a prescribed distance of separation with respect to a radioactivity counting medium in a radioactivity measurement instrument, which is sensitive to the radiation emanating from said radionuclide and which has a well, said step of loading said capillary tube including a. dipping the end of said capillary tube into a sample of said liquid thereby to load said capillary tube with a precise and reproducible predetermined reduced quantity of said liquid, the step of positioning said capillary tube including: b. placing said capillary tube loaded with said liquid in a compartment section of an assay tube, said compartment section with said loaded capillary tube contained therein being secured to one end of a spacer section of said assay tube with said loaded capillary tube supported therein on a supporting surface, c. inserting said opposite end of said spacer section into said well of said measurement instrument until said spacer section engages a cooperating surface of said measurement instrument to limit the movement of the assay tube in the well to a reproducible position in which said capillary tube is reproducibly spaced said prescribed distance from said counting medium, d. taking a measure of the radioactivity of said liquid in said capillary tube by said counting medium while said assay tube is held in said position in said well, said spacer section being proportioned to hold said loaded capillary tube at said prescribed distance from said counting medium, whereby the indication of said instrument is a measure of the radioactivity of said liQuid.
Claim 5
Dependent Claim
92 words
The method as defined in claim 1 further including the step of obtaining a calibration measure of said instrument using a calibration sample of a reference radionuclide substance in a capillary tube positioned at said prescribed distance of separation with respect to said counting medium, said calibration sample being proportioned in volume and activity to provide a normalized measure of radioactivity, whereby the radioactivity of said liquid is determinable directly by the ratio of the indication of said instrument for said liquid with the indication of said instrument for said reference substance.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-18 | 1975-10-18 | 1976-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-18 | 1979-10-18 | 1980-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-18 | 1983-10-18 | 1984-04-18 | $7700.00 | Window Closed / Lapsed |