Direct Elisa Test

By Ashley | April 8, 2010

ELISA is also referred to as the Enzyme linked immunosorbent assay. It is also known as the EIA or the enzyme immunoassay. It is the biochemical technique which is primarily used in immunology to help in detection of the presence of any antibodies or also to detect an antigen present in a given sample. The ELISA has been utilized in medicine as a diagnostic tool and also used in plant pathology. It is also used in various industries as the quality control check. Thus very simply in the ELISA a certain unknown quantity of eh antigen is first put on to a surface. Then a particular antibody is slashed over the surface to allow it to bind itself to that antigen. This particular antibody is then linked to the enzyme. The final step of this process involves a substance being added to the enzyme which will help to convert it to a detectable signal.

ELISA can be tested in the qualitative or the quantitative way. The qualitative results can simply result in a positive or the negative for the sample. The difference that is between the positive and the negative is arrived at by the particular analyst. This could also be statistical. In most cases, two or maybe three times the standard deviation would quite often be used to help to distinguish between the positive and the negative samples. While dealing with the quantitative ELISA, it is the main optical density and the fluorescent unit t that is changed into the standard curve that is basically the serial dilution which is used as a target.

Direct Enzyme-Linked Immunosorbent Assay or the ELISA is the method to detect and measure the antigen concentration the sample contains. Using the capture monoclonal antibody, one can detect the main presence of the specific antigen in the sample is . The sample which has the actual target antigen is then used to coat the microwell plates. , Binding of the antibody that is labeled is then quantified by the colorimetric, the chemiluminescent, or the fluorescent end-point. The direct ELISA is largely applied for the research or experimentation on how to detect and also quantify the large molecules with the multiple antigenic sites. This is normally a protein within the sample. It is also used to help test the recognition and the binding that lies between the antigen and the antibody. This is where the polyclonals are normally used. It is also used to make the ELISA when a pair of the monoclonal antibody is unavailable immediately.