Introduction to ELISA Technology

Enzyme-Linked Immunosorbent Assay (ELISA) is a widely used analytical technique in molecular biology and immunology for the quantitative measurement of specific proteins in various biological samples. These samples can include serum, plasma, cell culture supernatants, urine, and tissue lysates. AREX Biosciences is committed to providing high-quality ELISA kits that facilitate the detection and quantification of target proteins with exceptional specificity and sensitivity. Our innovative solutions cater to the needs of researchers and clinicians, making them invaluable in both research and clinical applications.

Overview of ELISA Methodology

The ELISA process involves several key steps to accurately measure target proteins. Initially, a specific capture antibody is immobilized on a 96-well plate. Following this, standards and samples are added to the wells, where the target protein binds to the immobilized antibody. The wells are then washed to remove unbound substances, followed by the addition of a biotinylated detection antibody that specifically recognizes the target protein. After another washing step, HRP-conjugated streptavidin is added to facilitate detection.

Development of Signal

After the addition of HRP-conjugated streptavidin, the wells undergo a final wash before a TMB substrate solution is introduced. The substrate reacts with the HRP enzyme to produce a color that is directly proportional to the amount of target protein bound to the wells. This color development is a critical aspect of the assay, allowing researchers to visualize and quantify the target protein effectively. AREX ensures that all components in its ELISA kits are optimized for reliable performance, contributing to accurate results in protein analysis.

Types of ELISA

There are four main types of ELISA: direct, indirect, sandwich, and competitive, each with distinct advantages and disadvantages.

• Direct ELISA: In this type, an antigen is immobilized on the plate, and a conjugated detection antibody binds directly to it. This method is fast and simple but less specific due to the use of only one antibody.
• Indirect ELISA: This variation includes an additional amplification detection step, where an unconjugated primary antibody is added first, followed by a conjugated secondary antibody. This approach allows for amplification of the signal but may introduce potential cross-reactivity.
• Sandwich ELISA: The most common type, this method employs two antibodies to "sandwich" the antigen. It offers the highest specificity and sensitivity but involves a longer protocol and may be more challenging to develop. AREX’s sandwich ELISA kits are designed to maximize performance, providing researchers with a reliable tool for their analyses.