Resultant color step indicator

• US 3,957,436 A
• Filed: 04/29/1974
• Issued: 05/18/1976
• Est. Priority Date: 04/29/1974
• Status: Expired due to Term

• Current Assignee: Kallestad Diagnostics Incorporated (Bio-Rad Laboratories Incorporated)
• Original Assignee: Kallestad Laboratories, Inc. (Government of France)
• Inventors: Murray, Dennis M.
• Primary Examiner(s): Scovronek, Joseph
• Application Number:
  US05/464,986
• Time in Patent Office: 750 Days
• Field of Search: 23/230 R, 23/230 B, 23/230 A, 23/230.3, 208/12, 44/59 (U.S. only), 116/114 R (U.S. only), 116/114 AM, 73/432 R (U.S. only)
• US Class Current: 436/513
• CPC Class Codes: G01N 33/52 Use of compounds or compositions for colorimetric, spectrophotometric or fluorometric investigation, e.g. use of reagent paper and including single- and multilayer analytical elements immunological elements G01N33/54386; involving labelled immunochemicals G01N33/58; for haemoglobin or occult blood G01N33/72
• CPC Class Codes: G01N 33/53 Immunoassay; Biospecific binding assay; Materials therefor
• CPC Class Codes: Y10S 436/804 Radioisotope, e.g. radioimmunoassay
• CPC Class Codes: Y10S 436/805 Optical property
• CPC Class Codes: Y10S 436/817 Steroids or hormones
• CPC Class Codes: Y10S 436/826 Additives, e.g. buffers, diluents, preservatives

Abstract

A resultant color step indicator for use in various diagnostic or analytic test procedures particularly useful in those involving qualitative and quantitative analysis, such as radioimmunoassay, where a number of steps must be accomplished consecutively in order to get a proper final measurement. The various reagents which must be consecutively added are colored with an inert coloring. The coloring does not enter into the chemical reaction that yields the test results. It serves only to combine or intermix with the other coloring to indicate which steps have been completed. As the test is run, each step in the procedure which involves the addition of a different colored reagent results in a color change in the test specimen and the resultant color of the test specimen indicates which steps in the procedure have been accomplished.

Claims

1. In a chemical process wherein a plurality of substances are to be mixed with a test substance in a sequence of discrete steps, the improvement comprising:

color coding 2 or more of the plurality of substances, each with a different inert color; and

sequentially mixing each of the plurality of substances with the test substance and any substances mixed with the test substance in previous steps, so that the addition of each color coded substance is effective to change the cumulative color of the previously mixed substances in an identifiable manner whereby the resultant color of the mixture after each addition of a color coded substance is a conclusive indication that the step of adding the color coded substance has been completed.

2. The chemical process of claim 1 wherein the plurality of substances to be added are in liquid form and wherein the substances are color coded with inert pigments which are in solution with the substances.

3. The chemical process of claim 1 wherein the plurality of substances to be added are reagents which are to be sequentially added to a liquid test solution and further comprising the step of color coding each of the reagents prior to their addition to the solution with different inert colors so that the sequential adding of each of the reagents to the solution causes the resultant color of the solution to change after each addition, thereby indicating the addition of each such reagent.

4. The chemical process of claim 3 wherein the process is an analytic test procedure wherein a plurality of reagents are sequentially added to the solution and wherein each reagent is color coded, each with a different inert pigment.

5. The chemical process of claim 1 wherein the process is radioimmunoassay wherein some of the plurality of substances to be added are liquid reagents which are consecutively added during the process to form a solution and wherein two or more of the reagents are color coded.

6. The chemical process of claim 5 wherein the process is HGH radioimmunoassay and wherein three reagents are sequentially added to the solution each of which is color coded with a different color.

7. The chemical process of claim 6 wherein the first of the three reagents to be added to the solution is colored blue, the second of the reagents to be added is colored yellow and the third of the reagents is colored red.

8. The chemical process of claim 5 wherein the process is IgE radioimmunoassay and wherein three reagents are sequentially added to the solution each of which is color coded with a different color.

9. The chemical process of claim 8 wherein the first of the three reagents to be added to the solution is colored yellow, the second of the reagents to be added is colored blue and the third of the reagents is colored red.

10. The chemical process of claim 1 wherein the improvement further comprises color coding all of the plurality of substances, each with a different inert color, whereby the resultant color of the mixture after each addition is a conclusive indication that each step in the process has been completed.