Immunoassay

From WikiMD's Wellness Encyclopedia

(Redirected from Immunoreactivity)

Introduction[edit | edit source]

Immunoassay is a biochemical test that measures the presence or concentration of a substance using the highly specific binding reaction between an antigen and an antibody. This test is a cornerstone in diagnostic laboratories for its sensitivity and specificity in detecting and quantifying biomolecules, including hormones, proteins, and pathogens.

Overview of Immunoassays[edit | edit source]

  • Function: Immunoassays are used to diagnose diseases, monitor therapy, and in research to understand disease mechanisms.
  • Principle: The test hinges on the natural immune response, where antibodies bind to specific antigens.
Illustration of an Immunoassay Procedure

Types of Immunoassays[edit | edit source]

  • Radioimmunoassay (RIA): Uses radioactive isotopes to detect antigens.
  • Enzyme-Linked Immunosorbent Assay (ELISA): Utilizes an enzyme linked to an antibody or antigen as a marker for detection.
  • Fluorescent Immunoassay: Involves antibodies labeled with a fluorescent dye.
  • Chemiluminescent Immunoassay: Uses a luminescent compound to produce light as a signal.

Applications in Medicine[edit | edit source]

  • Immunoassays play a critical role in various medical applications:
 * Diagnosing infectious diseases like HIV and hepatitis.
 * Hormone level testing, such as thyroid hormones and insulin.
 * Allergy testing through the detection of specific antibodies.
 * Drug level monitoring in the blood, essential for therapeutic drug management.
 * Identifying tumor markers, such as PSA for prostate cancer or CA-125 for ovarian cancer.

Advantages and Limitations[edit | edit source]

  • Advantages: High specificity and sensitivity, suitable for a wide range of substances, and relatively quick results.
  • Limitations: Cross-reactivity leading to false positives, requirement of standardization, and the need for skilled personnel and specialized equipment in some cases.

Technological Developments[edit | edit source]

  • Recent advancements in immunoassay technology include automation, miniaturization, and the development of point-of-care tests.

Immunoassays in Research[edit | edit source]

  • Beyond clinical diagnostics, immunoassays are invaluable in biomedical research for studying biomarkers, immune responses, and drug development.

Quality Control and Standardization[edit | edit source]

  • Ensuring the accuracy and reliability of immunoassay results is critical. Quality control measures and standardization protocols are essential components of laboratory practices.

References[edit | edit source]


External Links[edit | edit source]

See Also[edit | edit source]

Immunoassay Resources

Contributors: Prab R. Tumpati, MD