LAUSR

The rising of multidrug-resistant bacteria and their associated proliferation as harmful microorganisms boosted the creation of new antibacterial surfaces and biomaterials with applications ranging from health to food packing. Herein, low-cost antibacterial PVA:PVP copolymers containing cyanine derivatives (1, 2 and 3) and their respective Cu2+ complexes were successfully obtained and tested against Gram-negative and Gram-positive bacteria. The possible application in food packing was addressed by covering the surface of typical paper mockups with the doped polymers. All dye-doped polymers presented a broad-spectrum antibacterial effect against Gram-positive bacteria, especially for B.cereus, S. aureus and MRSA strains, with PVA:PVP@3 and PVA:PVP@3-Cu being the most effective. Moreover, polymers containing cyanine derivatives presented interesting inhibition effects against P. aeruginosa, where the production of its characteristic blue/green virulent pigment was not observed. Of the coated paper mockups, PVA:PVP:paper@2 and PVA:PVP:paper@2-Cu were most effective against B. cereus and S. aureus, while PVA:PVP:paper@3 and PVA:PVP:paper@3-Cu were most effective against the MRSA strain. In these formulations, direct contact inhibition mechanisms appear to be more significant than diffusional mechanisms, due to cyanine release hinderance, making them very interesting and versatile platforms for medical and food applications. This article is protected by copyright. All rights reserved.