Poly(amino acid)s-based star AIEgens for cell uptake with pH-response and chiral difference

Chiral aggregation-induced emission luminogens (AIEgens) are the new-generation chiral sensors that regulate chiral signals from the molecular level to the macroscopic assembly. Expanding applications of chiral AIEgens and in-depth understanding of their chiral recognition in biological systems are meaningful. Herein, two star chiral AIEgens, consisting of tetraphenylethene (TPE) as core and poly(N-acryloyl-L(D) valine) (PLV or PDV) as arms, were precisely synthesized via atom transfer radical polymerization (ATRP) technique and named TPE-PLV and TPE-PDV. They possessed typical AIE characteristics and exhibited an increase in concentration-dependent fluorescence intensity. The two AIEgens were pH-responsive and had strong AIE-related emission in acidic solution. Importantly, AIEgens can enter the living cells by ATP dependent endocytosis, then light them up. The interactions between the AIEgens and living human hepatocarcinoma (HepG2) cells revealed that the internalization process of TPE-PLV and TPE-PDV was both chiral-dependent and pH-responsive. This novel strategy for synthesizing poly(amino acid)s functionalized AIEgens could inspire the development of promising fluorescent materials with chirality.

Automated summary

Chiral aggregation-induced emission luminogens (AIEgens) are new-generation chiral sensors that regulate chiral signals from molecular to macroscopic levels. The study synthesized two star chiral AIEgens with pH-responsive characteristics, showing strong AIE-related emission in acidic solution. The research revealed that these AIEgens can enter living cells through ATP-dependent endocytosis and exhibit chiral-dependent and pH-responsive internalization processes in human hepatocarcinoma cells (HepG2). This novel strategy of synthesizing poly(amino acid)s functionalized AIEgens could inspire the development of promising fluorescent materials with chirality.