ASSAY PRINCIPLES
The r-Metolachlor Tube Kit uses a monoclonal antibody that bind both r-metolachlor and a metolachlor-enzyme conjugate. r-Metolachlor in the sample competes with metolachlor-enzyme conjugate for a limited number of antibody binding sites. Antibodies, which bind r-metolachlor, are immobilized to the inside of the test tubes. In the assay procedure you will:

•   Add a sample or calibrator to a test tube, followed by metolachlor-enzyme conjugate. The conjugate competes with any metolachlor in the sample for the same antibody binding sites.
•   Wash away any unbound molecules, after you incubate this mixture for 20 minutes.
•   Add clear substrate solution to each tube. In the presence of bound metolachlor-enzyme conjugate, the substrate is converted to a blue compound. One enzyme molecule can convert many substrate molecules.

Since the same number of antibody binding sites are available in every tube, and each tube receives the same number of metolachlor-enzyme conjugate molecules, a sample containing a low concentration of r-metolachlor allows the antibody to bind many metolachlor-enzyme conjugate molecules. The result is a dark blue solution.

Conversely, a high concentration of metolachlor allows fewer metolachlor-enzyme conjugate molecules to be bound by the antibodies, resulting in a lighter blue solution.

NOTE: Color is inversely proportional to metolachlor concentration.
Darker color = Lower concentration
Lighter color = Higher concentration