Antibacterial Photocurable Acrylic Resin Coating Using a Conjugate between Silver\nNanoclusters and Alkyl Quaternary Ammonium

Abstract

Ligand-protected\nsilver nanoclusters (Ag NCs) have been gaining\ninterest as antibacterial agents because of their ultrasmall sizes\n(<2 nm), their high antibacterial activity, and the variety of\nligand species. The incorporation of Ag NCs into polymer resins is\na desirable approach to achieve high durability and the long-term\nantibacterial activity of Ag NCs-based antibacterial coatings. However,\nthe Ag NC-based antibacterial agents reported thus far are all water-soluble,\nand they have not been employed to generate antibacterial resins coatings\nbecause of the hydrophobic nature of the resins. Herein, we report\nfor the first time Ag NC-based antibacterial photocurable acrylic\nresin coatings prepared by incorporating the conjugate of dihydrolipoic\nacid-capped Ag NCs with tetraoctyl­ammonium (TOA) (TOA-Ag NCs).\nGiven TOA’s organosolubility, TOA-Ag NCs readily dissolved\nin the acrylic resin. The Ag NC-based antibacterial resin coatings\ndisplayed efficient antibacterial activity descending from the double\nantibacterial action of Ag NCs and TOA. This activity was maintained\nfor a long time even after exposure of the coatings to aqueous environments.\nThe cytotoxicity of the Ag NC-based antibacterial resin coatings was\nevaluated by measuring NIH3T3 cell proliferation and the expression\nof F-actin and vinculin, and data supported the low cytotoxicity of\nthe coatings. These novel Ag NC-based antibacterial resin coatings\nhave promising potential biomedical applications, for instance in\nhealthcare/medical devices, for hospital infection prevention, and\nin implantable devices.