Microfluidic Engineering of Addressable Multicompartmental Microspheres for Multicellular Systems.

With the advantages of high-throughput manufacturing and customizability, on-microsphere construction of in vitro multicellular analytical systems has garnered significant attention. However, achieving a precise, biocompatible cell arrangement and spatial signal analysis in hydrogel microspheres remains challenging. In this work, a microfluidic method is reported for the biocompatible generation of addressable supersegmented multicompartmental microspheres. Additionally, these microspheres are developed as novel label-free multicellular systems. In the microfluidic approach, controllable microfluidics is used to finely tune the internal microstructure of the microspheres, and the gas ejector ensures the biocompatibility of the preparation process. As a proof of concept, six- and twenty-compartment microspheres were obtained without the addition of any biohazardous reagents. For microsphere decoding, the visualization of two basic compartments can provide clues for identifying label-free cells due to the structural regularity of the microspheres. Finally, by encapsulating cells of different types, these microspheres as multicellular systems were successfully used for cell coculture and drug testing. These biocompatible, scalable, and analyzable microspheres will open up new prospects for biomedical analysis.