A simplified cytokine immunoassay using magnetic polymer particles.

Accurate detection of cytokines is essential for understanding their biological role in the immune system. Various methods to detect cytokines have been developed, including sandwich enzyme-linked immunosorbent assay (ELISA) and flow cytometry-based methods. All of the currently available methods have limitations, however. These limitations include time and extensive handling in standard sandwich ELISAs and the need for specialized equipment in flow cytometry-based assays. We have developed a magnetic polymer cytokine immunoassay and demonstrate that this assay is rapid and simple, needs less handling and offers better dynamic range, compared to standard sandwich ELISA. Furthermore, it does not require flow cytometry equipment, which is often used in microparticle-based polymer immunoassays. The magnetic polymer cytokine immunoassay described in this study is as sensitive as a standard sandwich ELISA. Because the method is not limited to the use of magnetic polymer particles, it is versatile and compatible with a number of different solid matrixes.