Serum or Plasma Substance Concentration by Immunoassay (Tetramethylbenzidine-based)

What This Test Measures

This test uses an immunoassay technique with tetramethylbenzidine (TMB) to detect and quantify a specific substance in your blood. Immunoassays are highly sensitive and can identify proteins, hormones, or other molecules that may be linked to health conditions. The TMB method enhances detection sensitivity by producing a measurable color change when the target substance binds to antibodies.

How the Test Works

The test involves drawing blood, which is then processed into serum or plasma. The sample is mixed with antibodies specific to the target substance. If the substance is present, it binds to the antibodies, triggering a chemical reaction that produces a detectable signal (color change in TMB-based assays). The strength of the signal corresponds to the concentration of the substance in your blood.

Common Uses

This type of test may be used to screen for, diagnose, or monitor conditions such as infections, autoimmune diseases, or certain cancers. It can also help assess hormone levels, enzyme activity, or other biomarkers relevant to your health.

Possible Preparations

No special preparation is typically required for this test. You may be asked to fast for 8–12 hours before the blood draw if the test involves fasting-related substances, but this is not always the case. Follow your healthcare provider’s instructions if you have any specific instructions for your test.