Immunoassay Utilizing Trapping Conjugate

摘要

Test devices are provided for determining the presence of a first ligand in a sample. In some embodiments depletion conjugates are used to deplete the ligands different from but related to the first ligands from the sample. In some embodiments, interim binding agents are used to enhance the test signal.

主权项

1. A test device for determining the presence of a first ligand in a liquid sample, comprising:
a) a first sorbent strip having a first location for receiving a solution and defining a first migration path; b) a marker conjugate adapted to move along said first migration path and bind to said first ligand; c) a second sorbent strip distinct from said first sorbent strip and having a second location for receiving the liquid sample and defining a second migration path; d) depletion molecules located on or in said second migration path wherein said depletion molecules include an immobilized ligand-binding element adapted to bind to second ligands that are different from but related to said first ligand; and e) a test site located on or in one at least one of said first sorbent strip and said second sorbent strip, said test site having an immobilized first ligand binding mechanism for said first ligand, and said first and second sorbent strips touching each other at the test site location, wherein said second location is removed from said test site such that sample applied to said second location requires time to migrate to said test site and does not immediately wet said test site.