IMMUNOASSAY

“Radio immunoassays" (RIA) are simple, reliable and reproducible laboratory techniques used extensively in clinical laboratories for the last three decades world wide. This Nobel prize winning technique is based on the antigen-antibody reaction, imparts the highest degree of specificity, and utility of radioisotopes offers astonishing degree of sensitivity. They are primarily utilised in diagnosis and management of thyroid disorders and infertility tests.

Chemiluminescence is the generation of electromagnetic radiation as light by the release of energy from a chemical reaction. While the light can, in principle, be emitted in the ultraviolet, visible or infrared region, those emitting visible light are the most common. The chemiluminiscent enzyme reaction generates light and involves use of natural substrates such as luciferin -adenosine triphosphate.The lack of inherent background and the ability to easily measure very low and very high light intensities with simple instrumentation provide a large potential dynamic range of measurement. The technique is used in thyroid disorders and many other hormonal test.

ELISA (Enzyme Linked Immunosorbent Assay)

ELISA has replaced a number of more cumbersome and time consuming "classical" serological techniques, and has also widened the scope of the detection methods for viruses and their related markers of infection. The test measures whether a specific antibody associated with an illness can be found in a patient's blood. A positive result indicates that the antibody is there and implies that the person has encountered a particular disease. Used to detect the infectious disease like Tuberculosis, TORCH, etc. and tumour markers like CA125,PSA,BHCG,etc.