Polymer-chlorella cells conjugating with aggregation-induced functionality switch towards hydrogen evolution

The manipulation of physicochemical and biological properties of the encapsulated cells by cell surface engineering technique is now attracting more and more researchers’ interest. In this study, we showed a mild and highly efficient way to build a type of polymer-living cell conjugates based on photoinduced electron transfer-reversible addition-fragmentation chain-transfer polymerization (PET-RAFT). The polymerization could proceed at room temperature under the blue light initiating and showed very less influence on the activity of the living cells. Significantly, the constructed positively charged polymer-living cell conjugates could aggregate with the negatively charged native Chlorella pyrenoidosa (CP) cell to form a microscale aggregate which then allowed a functionality switching of the encapsulated CP cells from the normal photosynthetic O₂ towards H₂ production with an average rate of 0.26 µmol H₂h⁻¹ (mg chlorophyll)⁻¹ for 42 h. It is then anticipated that the method we show could contribute an effective way for generating different functionalized living cell polymer hybrid structures on demand, and the demonstrated aggregation induced functionality switching of the CP cells is also anticipated to inspire more applications of the cell based materials towards biology green energy.