Exosome ELISA Complete kit (CD9 detection) | EXOEL-CD9A-1

Sensitive, ELISA-based exosome quantitation

When you would like to use an ELISA-based method to find out how many exosomes you have and time is not limiting, choose one of SBI’s ExoELISA Complete Kits. Calibrated using NanoSight Analysis, the ExoELISA Complete Kit (CD9 Detection) enables calculation of exosome abundance based on the presence of CD9, a general exosome marker. Note that our newer ExoELISA-ULTRA Complete Kit (CD63 Detection) can provide faster exosome quantitation using significantly less sample.

• Sensitive—detect as little as 500 µg protein equivalent
• Flexible—compatible with all major exosome isolation methods (e.g. ExoQuick^®, ultracentrifugation, ultrafiltration, and immunoaffinity capture) from human, mouse, and rat
• Quantitative—calibrated internal standards enable quantitation of exosomes carrying CD9

The lysed exosome particles (and, thus, exosomal proteins) are directly immobilized onto the wells of the microtiter plate, and after binding, a blocking agent is added to prevent non-specific binding of the primary detection antibody, anti-CD9. Following addition of anti-CD9, a secondary antibody (goat anti-rabbit) linked to horseradish peroxidase (HRP) is also added to amplify the signal and increase assay sensitivity.

The amount of CD9 is measured via activity of the bound HRP-secondary antibody using a colorimetric assay with extra-sensitive TMB as the substrate. The accumulation of colored product is proportional to the amount of CD9 present in each well, and is measured using a microtiter plate reader at 450 nm absorbance.

Each ExoELISA Kit includes a set of standards calibrated to a known amount of exosome particles as determined by NanoSight analysis. These standards can be used to generate a calibration curve enabling quantitation of exosomes carrying CD9 from the ExoELISA data.