lab report 2

lab report 2 - 1 Various Methods of Identifying Specific...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Various Methods of Identifying Specific Antibodies and Antigens Introduction ELISA (Enzyme-linked immunosobent assay) tests, both direct and indirect, can be used clinically to detect antibodies or antigens. ELISA tests are the most widely used immunoassays in labs today due to the use of enzyme labels, which have high stability, reproducibility, safety, ease of detection, and has a low cost. ELISA tests work by adding a substrate to a specific enzyme. When the enzyme reacts with the substrate, a certain color is produced, which can be measured by a spectrophotometer. The higer the absorbance rate measure on the spectrophotometer, the higher the level of antibodies and antigens in solution. A direct ELISA test uses enzyme labeled antibodies to identify an antigen. The direct test starts off by adsorbing a known antibody to the wells in a microtiter plate. A sample is taken from the patient and added to the wells. If a specific antigen is present, it will bind to the antibody in the plate. Next, a second antibody specific for the antigen bound to the original antibody is added to the solution, and it will bind to the antigen forming a sandwich. Lastly an enzyme substrate is added and there is a visible color change, which determines the antigens present. An indirect test is testing for a specific antibody in a patients’ serum. In this technique, a known antigen is attached to the wells of the plate. Next, dilutions of the suspected antibody are added to the mix, the solution is washed, and then an enzyme-labeled antibody is added. The antibody is present if there is a visible color change. Another way of determining which antibodies and antigens are present in a serum is to examine a patient’s blood. The different blood types A, B, AB, and O all have 1
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
different antibodies and surface antigens. For instance, type A has A-surface antigens and anti-B antibodies in the plasma. Type B is the exact opposite.
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 6

lab report 2 - 1 Various Methods of Identifying Specific...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online