Polylysine complexes and their biomedical applications

• This review summarized the advanced development of the synthesis strategies of PLL • This review introduces the biomedical fields, where PLL are mainly utilized, such as cargo delivery, tissue adhesives, and antibacterial materials • The design and synthesis of various PLL-derived complexes can be further optimized for diverse disease treatments Poly-L-lysine (PLL) is a water-soluble biopolymer consist of repeating unit of L-lysine. It displays intrinsic non-antigenicity, antibacterial property, biocompatibility, and biodegradability, and facile synthesis procedure, therefore has attracted particular attention in various biomedical and pharmaceutical applications. Following a brief introduction to PLL synthesis, this review focuses on the significant advances of PLL and PLL-derived complexes utilized in cargo delivery, tissue adhesives, and antibacterial materials. Meanwhile, this review summarized the modification and optimization of PLL complexes for further clinical translational studies. The final section discusses the challenges and opportunities of PLL-based complexes in the biomedical areas.