Allylimidazolium salt based antibacterial polymer coatings produced by thiol–ene photocuring

Photocurable formulations containing trifunctional thiol, trifunctional ene, and antibacterial allylimidazolium salts have been employed for transparent antibacterial coatings. The antibacterial component 1-allyl-3-dodecylimidazolium salt (ADIm) is prepared and chemically attached to polymer networks using a one-step thiol–ene photocuring reaction. Ultra-small (USANS) and small angle neutron scattering (SANS) measurements show that the photocured polymers are loosely networked three-dimensional structures with a mass fractal of approximately 2.7±0.2. The minimum inhibitory concentration (MIC) for the ADIm was determined to be 500μg/ml and 15.63μg/ml for Escherichiacoli (Gram negative) and Staphylococcus aureus (Gram positive) bacteria, respectively. Coating formulations containing 10mol% of the antibacterial ADIm photocured on glass substrates showed strong antibacterial activity against environmental bacteria such as E. coli and/or S. aureus.