Lignin-based sustainable antifungal gel nanocoatings for disinfecting biomedical devices†

Abstract

There is growing awareness that utilizing lignin as a sustainable biopolymer has emerged as a promising avenue to address challenges in antimicrobial protection. However, the application of lignin to prevent the spread of fungal infections is a less explored area and needs attention. Traditional antifungal agents often highlight significant concerns related to toxicity and environmental impact. To overcome these limitations, lignin, a renewable and biodegradable polyphenolic compound derived from plant cell walls, proves to be a substantial candidate. In this work, lignin is employed as a precursor molecule for the development of a gel-based coating. Rapid gelation technology was immensely useful in fabricating these versatile antifungal coatings. The developed coatings were highly transparent (nearly 85% transmittance values) and water resistant. Furthermore, the incorporation of lignin-based photodynamic nanoconjugates into coatings provides a multifaceted approach to combat fungal growth, thereby enhancing durability and sustainability, which enhanced the photodynamic activity of the lignin nanocoatings by approximately 50 fold. This work highlights the synergistic potential of lignin-based sustainable nanocoatings combined with photodynamic activity for on-demand disinfection of biomedical instruments.