One-step silver coating of polypropylene surgical mask with antibacterial and antiviral properties

Ivan Vito Ferrari; Giulia Giuntoli; Anissa Pisani; Aida Cavallo; Paola Mazzetti; Rossella Fonnesu; Alfredo Rosellini; Mauro Pistello; Tamer Al Kayal; Antonino Cataldo; Roberto Montanari; Alessandra Varone; Micaela Castellino; Simonetta Antonaroli; Giorgio Soldani; Paola Losi

doi:10.1016/j.heliyon.2023.e23196

One-step silver coating of polypropylene surgical mask with antibacterial and antiviral properties

Heliyon. 2023 Dec 3;10(1):e23196. doi: 10.1016/j.heliyon.2023.e23196. eCollection 2024 Jan 15.

Authors

Ivan Vito Ferrari¹, Giulia Giuntoli¹, Anissa Pisani¹, Aida Cavallo¹, Paola Mazzetti², Rossella Fonnesu², Alfredo Rosellini², Mauro Pistello², Tamer Al Kayal¹, Antonino Cataldo³, Roberto Montanari⁴, Alessandra Varone⁴, Micaela Castellino⁵, Simonetta Antonaroli⁶, Giorgio Soldani¹, Paola Losi¹

Affiliations

¹ Institute of Clinical Physiology, National Research Council, Massa, 54100, Italy.
² Virology Unit, Pisa University Hospital, Pisa, Italy and Retrovirus Center, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, 56126, Italy.
³ ENEA, Casaccia Research Centre, Rome, 00123, Italy.
⁴ Department of Industrial Engineering, University of Rome Tor Vergata, Rome, 00133, Italy.
⁵ Department of Applied Science and Technology, Politecnico di Torino, 10129, Turin, Italy.
⁶ Department of Chemical Sciences and Technology, University of Rome Tor Vergata, Rome, 00133, Italy.

Abstract

Face masks can filter droplets containing viruses and bacteria minimizing the transmission and spread of respiratory pathogens but are also an indirect source of microbes transmission. A novel antibacterial and antiviral Ag-coated polypropylene surgical mask obtained through the in situ and one-step deposition of metallic silver nanoparticles, synthesized by silver mirror reaction combined with sonication or agitation methods, is proposed in this study. SEM analysis shows Ag nanoparticles fused together in a continuous and dense layer for the coating obtained by sonication, whereas individual Ag nanoparticles around 150 nm were obtained combining the silver mirror reaction with agitation. EDX, XRD and XPS confirm the presence of metallic Ag in both coatings and also oxidized Ag in samples by agitation. A higher amount of Ag nanoparticles is deposited on samples by sonication, as calculated by TGA. Further, both coatings are biocompatible and show antibacterial properties: coating by sonication caused 24 % and 40 % of bacterial reduction while coating by agitation 48 % and 96 % against S. aureus and E. coli, respectively. At 1 min of contact with SARS-CoV-2, the coating by agitation has an antiviral capacity of 75 % against 24 % of the one by sonication. At 1 h, both coatings achieve 100 % of viral inhibition. Nonetheless, larger samples could be produced only through the silver mirror reaction combined with agitation, preserving the integrity of the mask. In conclusion, the silver-coated mask produced by silver mirror reaction combined with agitation is scalable, has excellent physico-chemical characteristics as well as significant biological properties, with higher antimicrobial activities, providing additional protection and preventing the indirect transmission of pathogens.

Keywords: Antimicrobial properties; Silver coating; Silver mirror reaction; surgical masks.