Recent technological advancements at RayBiotech have broadened the options for multiplex protein detection even further. The RayBio® Competition-based Antibody Array (“E-Series”) is a novel array based on the competitive immunoassay principle used in our EIA kits. In this platform, a cocktail of biotin-labeled peptides is mixed with the sample and incubated with the array; the peptides and target proteins then competitively bind to an array of capture antibodies on a solid support. Like the sandwich-based arrays (C-Series, G-Series, and Quantibody), the competition-based array can be either quantitative or semi-quantitative. If quantitative data is desired, a cocktail of peptides (derived from the target protein sequences) serves as the standard mix for derivation of calibration curves.
The E-Series array has several important advantages. First, it enables the detection of proteins or small peptides for which no antibody pair exists, or for which antibody pairs cannot be developed. Like the EIA kits, this array requires only 1 antibody per target for signal output. Thus, the E-Series can detect targets not included in our sandwich-based array antibody pool.
Second, due to the high sequence homology of the peptide antigens, the E-Series antibodies have broad-species reactivity. The E-Series arrays are validated for rat, mouse, and human samples and have expected reactivity with many other mammalian species.
Third, this technology has enabled the very first quantitative antibody array that is available on both membrane and glass slide.
This novel array technology is patent-pending and available exclusively at RayBiotech.
10 different anti-adipokine antibodies are spotted onto membranes in an array format. A cocktail of 10 biotin-labeled adipokine peptides is spiked into the samples, and the labeled and unlabeled targets competitively bind to their corresponding antibodies. After a wash step, streptavidin-horseradish peroxidase (SA-HRP) is incubated with the arrays, which interacts only with the biotin-labeled adipokines bound to the antibody. The chemiluminescent array signals are directly proportional to the amount of biotinylated peptide-SA-HRP complex and inversely proportional to the amount of adipokines in the samples.