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A D V A N C E D M A T E R I A L S & P R O C E S S E S | J A N U A R Y 2 0 2 1 3 6 microbial concentration were recorded within minutes when numerable patho- gens were inoculated. This is in compar- isonwith their finding that only aone log decrease of infectious microbial agents on wrought copper sheets, after three hours of direct contact. Moreover, Lucas et al. found that copper-coated 3D print- ed ABS realized complete contact kill- ing of the inoculated microbes within 15minutes of exposure; copper-on-cop- per reached microbial inhibition after 10 minutes, and a five-minute elimina- tion period was identified for the cop- per cold spray coatings that included a 5 wt. % addition of silver, i.e., the sec- ond most oligodynamic elemental agent next to copper, into the feedstock. This included gram-positive Staphylo- coccus aureus , gram-negative Pseudo- monas aeruginosa , Candida albicans , gentamicin-methicillin–resistant S. au- reus , azlocillin-carbenicillin–resistant P. aeruginosa, and fluconazole-resistant C. albicans [23] . CONCLUSION This article invoked the non-neg- ligible nature of contact-mediated fo- mite transmission of SARS-CoV-2 from contaminated high-touch surfaces; dis- cussed Cu’s oligodynamic activity; and analyzed the performance and applica- tion of copper cold spray processing for the purpose of procuring antimicrobi- al and antiviral coatings with enhanced functionality. By introducing the pre- ventive role supersonically deposited antiviral copper coatings can play as a pandemic countermeasure, materi- als scientists and engineers can more readily engage in prospective optimiza- tion and deployment of antipathogen- ic Cu cold spray surfaces. For example, the discussion surrounding the link be- tween microstructure, atomic Cu ion diffusivity, and antiviral/antibacterial performance, provides materials re- searchers with a target microstructure that may be tunable via advanced pro- cessing parameter development. In- stalling antimicrobial Cu cold spray coatings as a technology well-suited for rapid inactivation of SARS-CoV-2 can enhance the resiliency of populations in the short-term. In the long-term, pro- longed public health benefits will also be achieved since the supersonically deposited Cu coatings remain antivi- ral and antibacterial for prolonged pe- riods of time, thus remaining functional when future pandemics (which could center upon a pathogen with a great- er tendency of disease transmission via fomite pathways) follow COVID-19. ~AM&P Lead image: 2019-nCoV spike protein, courtesy of Jason McLellan/University of Texas at Austin. For more information: Bryer C. Sousa, doctoral candidate, materials science and engineering, Worcester Polytech- nic Institute (WPI), 100 Institute Road, Worcester, MA 01609, bcsousa@wpi. edu, wpi.edu or Danielle L. Cote, assis- tant professor, materials science and engineering, WPI, dlcote2@wpi.edu, wpi.edu . References 1. S.F. Sia, et al., Pathogenesis and Transmission of SARS-CoV-2 in Gol- den Hamsters, Nature , 583 (7818), p 834–838, Jul. 2020, doi: 10.1038/ s41586-020-2342-5. 2. E. Mantlo, et al., Luminore Copper- Touch TM Surface Coating Effectively Inactivates SARS-CoV-2, Ebola and Marburg Viruses in vitro, medRxiv , 2020, doi: 10.1101/2020.07.05.20146043. 3. S. Behzadinasab, et al., A Surface Coating that Rapidly Inactivates SARS- CoV-2, ACS Appl. Mater. Interfaces , 12 (31), p 34723–34727, Aug. 2020, doi: 10.1021/acsami.0c11425. 4. N. Hutasoit, et al., Sars-CoV-2 (COVID-19) Inactivation Capability of Copper-Coated Touch Surface Fabricted by Cold-Spray Technology, Manuf. Lett. , 25, p 93–97, Aug. 2020, doi: 10.1016/ j.mfglet.2020.08.007. 5. N. van Doremalen, et al., Aerosol and Surface Stability of SARS-CoV-2 as Compared with SARS-CoV-1, N. Engl. J. Med. , 382 (16), p 1564–1567, Apr. 2020, doi: 10.1056/NEJMc2004973. 6. R. Shrestha, et al., Oligodynamic Action of Silver, Copper and Brass on Enteric Bacteria Isolated from Water of Kathmandu Valley, Nepal J. Sci. Technol. , 10, p 189–193, Jan. 1970, doi: 10.3126/njst.v10i0.2959. 7. E. Ladomersky and M. J. Petris, Copper Tolerance and Virulence in Bacteria, Metallomics , 7 (6), p 957–964, 2015, doi: 10.1039/C4MT00327F. 8. R. Balasubramanian, G.E. Kenney, and A.C. Rosenzweig, Dual Pathways for Copper Uptake by Methanotrophic Bacteria, J. Biol. Chem. , 286 (43), p 37313–37319, Oct. 2011, doi: 10.1074/ jbc.M111.284984. 9. K. Sundberg, Application of Materials Characterization, Efficacy Testing, and Modeling Methods on Copper Cold Spray Coatings for Optimized Antimicrobial Properties, Worcester Polytechnic Institute, 2019. Fig. 5 — Scanning transmission electron microscopy-based cross-sectional micrographs of the deformed microstructure of the nanostructured Cu cold sprayed coatings. A large amount of atomic lattice fringes is observed in the leftmost micrograph. Adapted from Sousa et al. [16] .