H2S gasotransmitter-responsive polymer vesicles.

Building biomimetic polymer vesicles that can sense a biological signaling molecule is a tremendous challenge at the cross-frontier of chemistry and biology. We develop a new class of o-azidomethylbenzoate (AzMB)-containing block copolymer that can respond to an endogenous signaling molecule, hydrogen sulfide (H2S). Such a gasotransmitter can trigger cascade chemical reactions to sever the AzMB side functionalities, which alters the polymer amphiphilicity and further leads to a controllable disassembly of their self-assembly vesicular nanostructure. Moreover, if we introduce cystathionine γ-lyase (CSE), a specific enzyme converting cysteine into H2S, onto the vesicle membrane, the polymersomes can extend their responsive scope from H2S to a specific amino acid bioactivator. We anticipate that this polymer model could open up a new avenue for constructing biosignal-triggered nanocapsules for intracellular applications.