Polyelectrolytic multilayers (PEMs) with enhanced antibacterial properties were built up onto commercial
poly(ethylene terephthalate) (PET) films based on the layer by layer assembling of bacterial contact
killing chitosan and bacterial repelling highly hydrated hyaluronic acid. The optimization of the aminolysis
modification reaction of PET was carried out by the study of the mechanical properties and the surface
characterization of the modified polymers. The layer by layer assembly was successfully monitored by
TEM microscopy, surface zeta-potential, contact angle measurements and, after labeling with fluorescein
isothiocyanate (FTIC) by absorption spectroscopy and confocal fluorescent microscopy. Beside, the
stability of the PEMs was studied at physiological conditions in absence and in the presence of lysozyme
and hyaluronidase enzymes. Antibacterial properties of the obtained PEMs against Escherichia coli were
compared with original commercial PET.