Biomedical Applications of Layer-by-Layer Self-Assembly for Cell Encapsulation: Current Status and Future Perspectives

Encapsulating living cells within multilayer functional shells is a crucial extension of cellular functions and a further development of cell surface engineering. In the last decade, cell encapsulation has been widely utilized in many cutting-edge biomedical fields. Compared with other techniques for cell encapsulation, layer-by-layer (LbL) self-assembly technology, due to the versatility and tunability to fabricate diverse multilayer shells with controllable compositions and structures, is considered as a promising approach for cell encapsulation. This review summarizes the state-of-the-art and potential future biomedical applications of LbL cell encapsulation. First of all, a brief introduction to the LbL self-assembly technique, including assembly mechanisms and technologies, is made. Next, different cell encapsulation strategies by LbL self-assembly techniques are explained. Then, the biomedical applications of LbL cell encapsulation in cell-based biosensors, cell transplantation, cell/molecule delivery, and tissue engineering, are highlighted. Finally, discussions on the current limitations and future perspectives of LbL cell encapsulation are also provided.