Supramolecularly reloadable antibacterial waterborne acrylic coating.

Antimicrobial surfaces play a crucial role in limiting the spread of infectious diseases and are a valuable tool in industrial and medical fields. However, the extensive adoption of these surfaces has been challenging to achieve because existing solutions frequently exhibit cost-related issues, limited effectiveness against various microorganisms, and short-lived efficacy. In this thesis, an acrylic paint based on waterborne latex particles is presented. The paint can be supramolecularly coordinated with active compounds carrying a positive charge, which are able to provide a strong antimicrobial efficacy. The chemical characterization of the coating involved the use of different techniques in order to gain in-depth insights into the coating's chemical composition and structure. More specifically, the morphology of the coating and the appearance of bacteria after contact with the antibacterial coating have been investigated with Scanning Electron Microscopy (SEM). The robustness of this coating applied to different types of surfaces has been assessed, as well as its chemical resistance after contact with some selected detergent solutions. The surface's response to contact and multiple washings using common industrial detergents has also analyzed, leading to the selection of the optimal cleaning solution for maintaining effective antibacterial properties without compromising the coating's chemical composition. In addition, the slow release of active compounds coordinated with the coating allows for long-lasting antibacterial action avoiding the leach of contaminants in water waste produced during the cleaning process. The antibacterial efficacy against Gram-positive and Gram-negative bacteria, respectively Staphylococcus aureus and Escherichia coli, results in a reduction of residual bacteria loading on the surface by more than 3log10 This efficacy lasts for more than 90 washes with water and, once lost, can be easily restored by spraying an aqueous solution of the antibacterial compound.