Bead-Based Immunoassays

Detect <1 pg/mL of Cytokine

The BD™ Cytometric Bead Array (CBA) Enhanced Sensitivity Flex Set system, based on the established BD CBA Flex Set system and proprietary detection technology, provides a new level of detection compared to other multiplex assay systems. Most bead assays can detect down to 5–10 pg/mL. The Enhanced Sensitivity Flex Set assays can detect as low as 0.274 pg/mL—more than a 35-fold improvement. This breakthrough allows researchers to get quantitative results in samples (eg, cultures at early time points) that were previously below the level of detection. The system includes assays for 10 different cytokines involved in inflammation and leucocyte differentiation, which can be combined to create a multiplexed panel. The system provides a reliable, flexible method for quantitative detection of multiple proteins in a single serum, plasma, or tissue culture supernatant sample.


More data in less time from a single sample

Multiplexing is especially useful because it maximizes the number of proteins that can be analyzed in a small amount of sample. Analyze up to 10 proteins with just 25 to 50 μL of sample using the Enhanced Sensitivity Flex Set system. Other methods such as ELISA require a similar amount of sample, but can analyze only one protein from the same volume. Because such a small amount of sample is needed, multiplexing reduces hands-on time as well as time to results.

Flexible and ready to use

Based on the established BD CBA Flex Set system and its proprietary detection technology, Enhanced Sensitivity Flex Set assays are formulated for combination into any size plex. They are sold individually to provide a highly flexible system. A dedicated master buffer kit contains all the buffers needed for the assay as well as an optimized protocol for performing the assay.

Robust assay system

All assays have been characterized for performance in single-plex and multiplex scenarios to ensure consistent data. The antibody pair in each assay is evaluated for dynamic range, sensitivity, and parallel titration to native biological samples. Results from samples containing levels of analyte detectable using the standard BD CBA Flex Set assay correlated with the Enhanced Sensitivity Flex Set assay. The optimized assay protocol ensures low background and superior signal-to-noise while using a two-step detection protocol.

Instrument Reporter Parameters Clustering Parameters
BD FACSVerse™ flow cytometer PE CBA Red and CBA NIR
BD Accuri™ C6 flow cytometer* FL2 FL4 (675/25) and FL3 (780/60)
BD FACSArray™ bioanalyzer Yellow Red and NIR
BD FACSCanto™ II flow cytometer PE APC and APC-Cy™7
BD LSRFortessa™ flow cytometer PE APC and APC-Cy7
BD FACSAria™ III cell sorter PE APC and APC-Cy7
BD FACSCalibur™ flow cytometer FL2 FL4 and FL3


*Requires the BD Accuri Selectable Laser Module (Cat. No. 653126)

Cy™ is a trademark of Amersham Biosciences Corp. Cy™ dyes are subject to proprietary rights of Amersham Biosciences Corp and Carnegie Mellon University and are made and sold under license from Amersham Biosciences Corp only for research and in vitro diagnostic use. Any other use requires a commercial sublicense from Amersham Biosciences Corp, 800 Centennial Avenue, Piscataway, NJ 08855-1327, USA.

FCAP Array is a trademark of Soft Flow Hungary Ltd.