Substituted carboxyfluoresceins

• US 4,476,229 A
• Filed: 11/08/1982
• Issued: 10/09/1984
• Est. Priority Date: 11/08/1982
• Status: Expired due to Term

• Current Assignee: Abbott Laboratories Incorporated
• Original Assignee: Abbott Laboratories Incorporated
• Inventors: Kirkemo, Curtis L., Fino, James R.
• Primary Examiner(s): Nucker, Christine M.
• Application Number:
  US06/440,067
• Time in Patent Office: 701 Days
• Field of Search: 436/500, 436/537, 436/546, 436/800, 549/223
• US Class Current: 436/500
• CPC Class Codes: C07D 311/82 Xanthenes
• CPC Class Codes: G01N 33/78 Thyroid gland hormones , e.g. T3, T4, TBH, TBG or their receptors
• CPC Class Codes: Y10S 436/80 Fluorescent dyes, e.g. rhodamine

Abstract

This disclosure relates to a method and reagents for determining ligands in biological fluids such as serum, plasma, spinal fluid, amnionic fluid and urine. This disclosure also relates to a novel class of tracer compounds employed as reagents in fluorescence polarization immunoassays.

Claims

1. A compound of the formula:

##STR15## wherein T is a ##STR16## wherein n is an integer of from 1 to 8; and

R is a ligand-analog having at least one common epitope with a ligand so as to be specifically recognizable by a common antibody;

and biologically acceptable salts thereof.

2. A compound according to claim 1 wherein R is a thyroxine analog.

3. A compound according to claim 2 wherein R is ##STR17##

4. A compound according to claim 3 wherein n is an integer of from 2 to 4.

5. A compound according to claim 4 wherein n is 3.

6. A method for determining ligands in a sample comprising intermixing with said sample a tracer of the formula:

##STR18## wherein T is a ##STR19## wherein n is an integer of from 1 to 8; and

, R is a ligand-analog having at least one common epitope with a ligand so as to be specifically recognizable by a common antibody;

and biologically acceptable salts thereof; and

an antibody capable of specifically recognizing said ligand and said tracer; and

then determining the amount of tracer bound to antibody by fluorescence polarization techniques as a measure of the amount of ligand in the sample.

7. A method according to claim 6 wherein R" has a molecular weight within a range of 50 to 4000.

8. A method according to claim 7 wherein R is a thyroxine analog.

9. A method according to claim 8 wherein R is ##STR20##

10. A method according to claim 6 or 9 wherein n is an integer of from 2 to 4.

11. A method according to claim 10 wherein n is 3.