Enzyme-linked Immunoassay

In 1971, Engvall and Perlmann published an article on enzyme-linked immunoassay (ELISA) for the determination of IgG. This laboratory test measures the concentration of an analyte, which is usually an antibody or antigen in a specific solution. ELISA binds soluble antigens or antibodies to a solid-phase carrier, and uses antigen-antibody specific binding for qualitative and quantitative detection of immune responses, which distinguishes it from other similar types of tests.

The Workflow of ELISA

The basic procedure of ELISA starts with the coating step. In this step, the polystyrene plate is covered with a solution containing antibodies or antigens. Then pour the liquid and wash the plate. Next is the blocking step. In this step, a protein-based solution that is not related to the first solution covers the unbound sites on the plate. Remove the liquid again and wash the plate. In the detection step, the enzyme-conjugated antigen or antibody binds to the target antigen or antibody. The plate is drained and washed again. Finally, the substrate is placed in the plate and the signal given by the reaction between the enzyme and the substrate is measured.

The Types of ELISA

There are four different types of ELISA:

• Direct ELISA. This method is the fastest, with fewer steps, and it is also less error-prone.
• Indirect ELISA. This method is highly sensitive and less costly due to the need for fewer labeled antibodies.
• Sandwich ELISA. With this method, more steps are involved, but the result is highly specific.
• Competitive ELISA. The method is generally used when only one antibody is available or the analyte is small.

Applications of ELISA

Creative Biogene provides a variety of ELISA kits that can detect hundreds of different proteins and molecules, including cytokines, growth factors, disease markers, drugs, and small molecules. ELISA kits are widely used in clinical diagnosis and have practical value in various diseases such as cancer, blood diseases, autoimmune diseases and infectious diseases, et al.

Advantages of ELISA

The ELISA test kit is a fast, convenient and accurate research tool for the detection and quantification of targets in cultures and samples. We offer a variety of assays, including traditional sandwich ELISA kits, competitive ELISA kits, and cell-based ELISA kits for many targets. Each kit is subjected to strict quality control and stability testing to ensure the accuracy, sensitivity, specificity and repeatability of the test.

Creative Biogene has a professional team of experts who developed quality ELISA test kits. Our products are competitive in the market due to their reasonable price and high quality, which can help you solve the diagnosis problem quickly. We look forward to working with you for your cooperation.

Please contact us for more details.

References

1. Engvall E and Peter P. (1971)."Enzyme-linked immunosorbent assay (ELISA) quantitative assay of immunoglobulin G." Immunochemistry. 8.9: 871-874.
2. Iha K, et al. (2019). "Ultrasensitive ELISA developed for diagnosis." Diagnostics. 9.3: 78.