Polyurethanes from Hydrophobic Elastic Materials to Hydrogels with Potent Nonleaching Biocidal and Antibiofilm Activity

The present work considers designing bioactive and biocidal thermoplastic PU materials with inherent fast and nonleaching antibacterial activity to address their present shortcomings in biomedical applications. For this, we have prepared a series of multiapplicable guanidine-modified thermoplastic polyurethane by grafting different amounts of polyguanidine to the uretdione-containing thermoplastic polyurethane. Our conceptually unique design generates PHMG-UPUs that offer a broad range of physicomechanical properties from hydrophobic elastic polyurethane materials to highly elastic hydrogels that could meet the requirements of different applications, including antibacterial coating, biomedical devices (catheters), and wound dressing. All materials displayed fast and efficient contact-active biocidal activity against Gram-negative and Gram-positive bacteria and superior antibiofilm activity. The support of fibroblast cell growth and moderate-to-excellent cell viability ranging from 95 to ∼65% is also observed. This study introduces a prospective strategy to tune the mechanical and biological properties of thermoplastic polyurethane for various biomedical applications in a simple way.