The High Potential of -Poly-l-Lysine for the Development of Antimicrobial Biomaterials

epsilon-poly-l-lysine (epsilon-PLL) is a natural polypeptide/polycation originating from bacteria. Thanks to its antifungal and antibacterial properties, it is the subject of extensive research in the food and medical industries. epsilon-PLL is also used to develop biomaterials in a broad range of applications, such as drug delivery, wound healing, or antimicrobial coatings. Indeed, loading epsilon-PLL inside nanoparticles, functionalizing implant surfaces with epsilon-PLL, or developing hydrogels based on reactions between epsilon-PLL and other polymers can improve the materials properties, leading to biocompatible, antibacterial, and antifungal systems. These characteristics are necessary not only for the development of biomaterials, for their integrity in a biological environment, but also for improving the performances of medical devices. Moreover, epsilon-PLL can be used as an alternative to antibiotics as its mechanism of action reduces the bacterial resistance risk compared with antibiotics. Finally, "smart" systems using epsilon-PLL may be developed, with controllable material degradation or drug delivery via pH or temperature variations. This review sought to gather the latest research on the development of antimicrobial biomaterials based on the epsilon-PLL polypeptide.