Polymer Materials Synthesized through Cell-Mediated Polymerization Strategies for Regulation of Biological Functions

ConspectusAs essential components of living organisms, biomacromolecules construct cell scaffolds and regulate cell activities and biological functions through chemical transformations in biological systems. Inspired by the functional evolution in the formation of natural structures, in situ polymerization methods have been developed to create functional synthetic macromolecules inside or on the surface of living cells. Given the diversity of cell species and the complexity of biological pathways, selected strategies can be employed to control the synthesis of functional polymers that utilize the dynamic cellular microenvironment.In this Account, we summarize recent work in the field of designing cell-mediated in situ polymerization methods, with which we demonstrate their application prospects including tumor cell labeling and treatment, microbial photosynthetic efficiency regulation, and hydrogel generation. The purpose of these efforts is to design polymerization reactions in response to endogenous or exogenous stimuli and to describe the underlying response mechanisms. By reasonable design of molecular structures, in situ synthesized polymers in the cell microenvironment implement regulation of biological functions. For example, using specific redox activity combined with light irradiation, bacteria can mediate the generation of functional polymers as the encapsulating matrix or with antibacterial effects. Conjugated polymers synthesized on the microalgae surface expanded the spectral absorption and improved photosynthetic efficiency. Meanwhile, characteristics of the cellular microenvironment could initiate various polymerization reactions inside living cells, including oxidative thiol cross-linking, condensation polymerization, and free radical polymerization. These reactions can be selectively conducted with reactive species generated in tumor cells, and the resulting polymers showed prolonged retention inside cells for modulating cell behaviors. Further development of cell-mediated polymerization strategies would provide an innovative platform for research and applications of multifunctional biomaterials and engineered biohybrid systems.