ELISA (enzyme-linked immunosorbent assay) is a commonly used application for the detection of antigens in a microwell format. The assay may be performed using the direct, indirect, or sandwich method and requires the use of a substrate that produces soluble end products. The results can be qualitative or quantitative, where specific levels of product are read in a spectrophotometer or luminometer. In a properly optimized assay, the intensity of color, or light, generated is directly proportional to the amount of reactant present. KPL provides a variety of reagents designed for all levels of users, from the beginner to the experienced researcher.

ELISA Substrates

KPL offers a variety of standard and proprietary chromogenic and chemiluminescent ELISA substrates that can be used with alkaline phosphatase or horseradish peroxidase. Chromogenic substrates produce a colored end product, which can be detected and measured visually or with the use of a spectrophotometer. Chemiluminescent substrates produce light, which can be measured using a luminometer or permanently recorded through exposure to X-ray film. Chemiluminescent substrates provide higher sensitivity than chromogenic substrates.

Protein Detector ELISA Kits

Protein Detector ELISA kits provide a convenient starting point for the development of ELISA protocols. Each kit includes a comprehensive instruction manual for developing enzyme immunoassay procedures as well as pretested components including blocking, coating and wash solutions along with affinity-purified conjugates. KPL offers Protein Detector ELISA kits with anti-mouse, anti-rabbit or anti-human secondary antibodies labeled with alkaline phosphatase (AP) or horseradish peroxidase (HRP).

See our Technical Guide for ELISA for an understanding of the many factors influencing ELISA performance.