Antifouling ability of polyethylene glycol of different molecular weights grafted onto polyester surfaces by cold plasma

Different molecular weights of polyethylene glycol (PEG, MW 200, 400, 600, 2000, and 4600) were grafted onto silicon tetrachloride (SiCl(4)) plasma functionalized polyethylene terephthalate (PET) surfaces. Dramatic increase of the C-O peak in the C1s high-resolution spectra determined by electron spectroscopy for chemical analysis suggests that PEG was successfully grafted. PEG-grafted PET showed significant inhibition of attachment and biofilm formation by Salmonella enterica sv. Typhimurium compared to unmodified PET. The antifouling ability of PEG-grafted PET surfaces was affected by the molecular weight of PEG and PEG2000 was the most effective. Both PEG600- and PEG2000-grafted PET also significantly inhibited biofilm formation by Listeria monocytogenes. Stability tests showed that over 2-month storage under ambient conditions PEG2000-grafted PET demonstrated reduced antifouling ability, but still significantly reduced biofilm formation by S. enterica sv. Typhimurium.