Claims
- 1. An assay for confirming the presence of a ligand in a biological sample, the sample having been tested previously utilizing a binding substance specific for the ligand and found positive for the ligand, the assay comprising:
- a) contacting the sample with microparticles which have been coated with a binding substance specific for the ligand for a time and under conditions sufficient for the ligand to bind to said microparticles
- b) removing said microparticles which have been coated with a binding substance specific for the ligand from said sample thereby forming a supernatant sample; and
- c) retesting said supernatant sample for presence of the ligand to determine if ligand has been removed with the removal of the microparticles, wherein a negative result upon retesting confirms the previous positive assay result.
- 2. The assay of claim 1 wherein the ligand is antibody to hepatitis B core antigen.
- 3. The assay of claim 1 wherein said microparticles are removed by centrifugation.
- 4. The assay of claim 1 wherein the binding substance on the microparticles is different than the binding substance used in the previous test.
- 5. The assay of claim 1 wherein the biological sample is assayed with control microparticles along with the microparticles which have been coated with a binding substance specific for the ligand.
- 6. An assay for confirming the presence of antibodies to hepatitis B core antigen in a biological sample, the sample having been previously tested and found positive for anti-HBc antibody utilizing a binding substance specific for anti-HBc antibody, the assay comprising:
- a) contacting the sample with microparticles which have been coated with hepatitis B core antigen for a time and under conditions sufficient for anti-HBc antibody to bind to said microparticles;
- b) removing said microparticles which have been coated with hepatitis B core antigen from said sample thereby forming a supernatant sample; and
- c) retesting said supernatant sample for presence of anti-HBc antibody to determine if anti-HBc antibody has been removed with the removal of the microparticles, wherein a negative result upon retesting confirms the previous positive assay result.
- 7. The neutralizing assay of claim 6 wherein the microparticles are removed by centrifugation.
- 8. The assay of claim 6 wherein the hepatitis B core antigen on the microparticles is different than the binding substance for anti-HBc in the previous test.
Parent Case Info
This is a continuation of U.S. application Ser. No. 314,669, filed Feb. 21, 1989, now abandoned, which is a continuation of U.S. application Ser. No. 006,419, filed Jan. 21, 1987, now abandoned.
US Referenced Citations (5)
Continuations (2)
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Number |
Date |
Country |
Parent |
314669 |
Feb 1989 |
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Parent |
6419 |
Jan 1987 |
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