Serum or plasma concentration of a substance measured by immunoassay (e.g., protein or hormone)

What This Test Measures

An immunoassay detects and quantifies a particular substance in your blood, such as certain proteins, hormones, or other biomarkers. This method relies on antibodies or other binding molecules to identify and measure the target substance accurately. The test may be used to screen for or monitor conditions related to these substances.

Common Uses

This type of test is commonly used in screening for conditions like hormone imbalances, infections, or metabolic disorders. It may also be part of routine monitoring for chronic conditions, such as diabetes or thyroid disorders, depending on the specific analyte being measured.

How the Test Works

Blood is drawn and processed to separate serum or plasma. The sample is then analyzed using an immunoassay technique, which involves mixing the sample with specific antibodies or probes that bind to the target substance. The binding reaction is detected and measured to determine the concentration of the substance in your blood.

Preparation and Sample Collection

No special preparation is usually needed for this test. You may be asked to fast for a few hours before the blood draw if the test involves certain substances that are affected by food. A healthcare provider will collect a blood sample, typically from a vein in your arm, and send it to the lab for analysis.