Combination of vancomycin and guanidinium-functionalized helical polymers for synergistic antibacterial activity and biofilm ablation

The emergence of various resistant bacteria and overuse of antibiotics have led to severe side effects. Therefore, developing efficient and safe antibacterial systems is important. Herein, well-defined antimicrobial material-helical poly(phenyl guanidinium isocyanide) block copolymers with different conformations (l-P3-van, d-P3-van, and dl-P3-van) that connect vancomycin (van) to the polymer through a disulfide bond were synthesized. The prepared antimicrobial materials exhibit broad-spectrum antimicrobial activity, low bacterial resistance, and good proteolytic stability. They also overcome the intrinsic resistance of Gram-negative bacteria to van with a 100-fold increase in antimicrobial activity. Interestingly, the conformation of the material promotes its antimicrobial activity. The left-handed helix conformation shows five-fold more antimicrobial activity than the right-handed helical conformation, thereby opening a path for the application of nanochirality in the field of antibiotics.

Automated summary

The overuse of antibiotics and the emergence of resistant bacteria have raised serious concerns, highlighting the need for the development of efficient and safe antibacterial systems. In this study, antimicrobial materials were synthesized by connecting vancomycin to helical poly(phenyl guanidinium isocyanide) block copolymers with different conformations. These materials exhibited broad-spectrum antimicrobial activity, low bacterial resistance, and good proteolytic stability. Moreover, they were able to overcome the inherent resistance of Gram-negative bacteria to vancomycin, showing a 100-fold increase in antimicrobial activity. Interestingly, the conformation of the material played a role in promoting its antimicrobial activity, with the left-handed helix showing higher activity compared to the right-handed helix.