Clickable Multifunctional Dumbbell Particles for in Situ Multiplex Single-Cell Cytokine Detection

We report a novel strategy for fabrication of multifunctional dumbbell particles (DPs) through click chemistry for monitoring single-cell cytokine releasing. Two different types of DPs were prepared on a large scale through covalent bioorthogonal reaction between methyltetrazine and trans-cyclooctene on a microchip under a magnetic field. After collection of the DPs, the two sides of each particle were further functionalized with different antibodies for cell capturing and cytokine detection, respectively. These DPs labeled with different fluorescent dyes have been used for multiplex detection and analysis of cytokines secreted by single live cells. Our results show that this new type of DPs are promising for applications in cell sorting, bioimaging, single-cell analysis, and biomedical diagnostics.