Antibacterial poly(ethyl methacrylate) surfaces constructed by facile amination with polyethyleneimine of different architectures

Polymethacrylate and its derivatives are widely used in food industry and biomedical applications for their plasticity, biocompatibility and optical transparency. However, susceptibility to bacterial growth on their surfaces limits their applications. In this study, linear and branched polyethyleneimine (PEI) molecules were grafted onto poly(ethyl methacrylate) (PEMA) via aminolysis using a simple one-step method to enhance the antibacterial properties of PEMA films. PEI-modified PEMA films were characterized by ATR-FTIR, X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM) and thermal gravimetric analysis (TGA). The modified films exhibited optimal bactericidal efficiency of 98.0% against Escherichia coli (E. coli) and over 99.9% against Staphylococcus aureus (S. aureus) . Furthermore, hydrolysis was found to contribute to anchoring PEI onto PEMA as well. Though branched PEI exhibited a higher grafting amount than the linear ones under same conditions, PEMA modified with linear PEI presented a similar or even higher antibacterial efficiency than those grafted with branched PEI. Overall, PEI-grafted PEMA films prepared with simple one-step method exhibit effective antibacterial properties and good biocompatibilities, making them promising candidates for biomedical devices and other applications.