key: cord-0765830-6op6kxan authors: Liu, L.T.; Chin, A.W.H.; Yu, P.; Poon, L.L.M.; Huang, M.X. title: Anti-pathogen stainless steel combating COVID-19 date: 2021-11-25 journal: Chem Eng J DOI: 10.1016/j.cej.2021.133783 sha: e0dc082febfcfc45c7726d20a190283b427039e8 doc_id: 765830 cord_uid: 6op6kxan Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exhibits strong stability on conventional stainless steel (SS) surface, with infectious virus detected even after two days, posing a high risk of virus transmission via surface touching in public areas. In order to mitigate the surface toughing transmission, the present study develops the first SS with excellent anti-pathogen properties against SARS-COV-2. The stabilities of SARS-CoV-2, H1N1 influenza A virus (H1N1), and Escherichia coli (E.coli) on the surfaces of Cu-contained SS, pure Cu, Ag-contained SS, and pure Ag were investigated. It is discovered that pure Ag and Ag-contained SS surfaces do not display apparent inhibitory effects on SARS-CoV-2 and H1N1. In comparison, both pure Cu and Cu-contained SS with a high Cu content exhibit significant antiviral properties. Significantly, the developed anti-pathogen SS with 20 wt.% Cu can distinctly reduce 99.75% and 99.99% of viable SARS-CoV-2 on its surface within 3 and 6 hours, respectively. In addition, the present anti-pathogen SS also exhibits an excellent inactivation ability for H1N1 influenza A virus (H1N1), and Escherichia coli (E.coli). Interestingly, the Cu ion concentration released from the anti-pathogen SS with 10 wt.% and 20 wt.% Cu was notably higher than the Ag ion concentration released from Ag and the Ag-contained SS. Lift buttons made of the present anti-pathogen SS are produced using mature powder metallurgy technique, demonstrating its potential applications in public areas and fighting the transmission of SARS-CoV-2 and other pathogens via surface touching. The transmission of pathogenic bacteria and viruses in public areas has been a long-40 standing issue for public health. Infectious diseases induced by these bacteria or viruses 41 are not only afflicting millions of people annually but also causing an immeasurable 42 economic cost [1] [2] [3] . In particular, the current coronavirus disease 2019 (COVID-19) is 43 causing a global pandemic [1, 4] . Centers for disease control and prevention (CDC) has autoclave before the test. A 5 μL droplet of SARS-CoV-2 (6.2 x 10 7 TCID 50 ·mL -1 ) was 137 applied on each metal surface. The virus was allowed to dry and incubate for different 138 time durations at the ambient condition (at 22~23°C, 60~70% relative humidity). After incubation, the metal discs were immersed in a 300 μL viral transport medium (VTM, 140 containing 0.5 w/v% bovine serum albumin and 0.1 w/v% glucose in Earles's balanced 141 salt solution, pH 7 -7.5) for 30 minutes at the ambient temperature to elute the virus. The eluted virus was titrated with Vero E6 cells by TCID 50 assay as described [32] . The heat-treated samples were cut into corrosion specimens of 10 mm × 10 mm × 1 203 mm. All specimens were polished by SiC papers to 1200 grits. A typical three-electrode 204 cell setup containing 0.9 wt% NaCl solution was adopted. Platinum (Pt) and a saturated 205 calomel electrode (SCE) were used as the counter electrode and reference electrode. Before the test, an open circuit potential (OCP) process for 3600 seconds was conducted 207 to form a fresh surface. Next, a potential scan rate of 1 mV·s -1 was used to measure the 208 potentiodynamic polarization curve of each specimen. Pitting potential (E p ) was 209 defined as the potential at which current density exceeded 10 −5 A·cm −2 . Three 210 independent tests were conducted for each material. and 99.99% of viable SARS-CoV-2 on its surface within 3 and 6 hours, respectively. Furthermore, in order to demonstrate their potential applications in public areas, press 253 buttons of lifts were fabricated using SS-20Cu (Fig. 1B) . As exhibited, since no hot 254 forging or rolling process is required for PM technology, such anti-pathogen SS 255 products of high Cu content are suitable for mass production. Fig. 5A (ii) and B (ii), massive Cu-rich precipitates with sizes ranging from sub-micron to tens of microns are present in the matrix. In addition, 275 HAADF images (Fig. 5A (iii) and B (iii)) and the corresponding EDX images (Fig. 5, 276 A(iv) and B(iv)) show that intensive nano-sized Cu-rich precipitates are also present in 277 the matrix of both SS-10Cu and SS-20Cu. The EDX spectrums of the precipitates in 278 the SS-10Cu and SS-20Cu (Fig. 5A (v) and B (v) ) also indicate that these precipitates 279 are rich in Cu. In addition, the TEM-EDX results indicate that solid solution Cu atoms 280 could also be present in the matrix. The strength and ductility of the SS are also the concerning property for applications. firstly in this research (Fig. 2) . However, the remaining viable SARS-CoV-2 on pure 334 Ag and Ag-contained SS is similar to that of the 316L SS even after 24 hours. Interestingly, for pure Cu, SS-20Cu, and SS-10Cu, no viable SARS-CoV-2 can be 351 detected after 6, 12, 24 hours (Fig. 2) , and no viable H1N1 can be detected after 3, 6, 352 12 hours (Fig. 3) , respectively. This agrees with the previous findings that SARS-CoV- property. In addition, the present anti-pathogen SS can be directly employed for industrial production by the current PM technology to replace part of the conventional 394 stainless steel products in public areas. As the first trial production, SS-20Cu lift buttons 395 have been successfully produced for demonstration (Fig. 1B) . Besides, it is reasonable 396 to assume that present anti-pathogen SS will not have significant harmful effects on 397 users in the public areas as the duration of surface touching is very short, which still 398 needs further study. It is widely accepted that Cu has a broad-spectrum antibacterial property, which can Genomic characterisation and 440 epidemiology of 2019 novel coronavirus: implications for virus origins and receptor binding influenza: the mother of all pandemics Existence and control of Legionella bacteria in building water 445 systems: A review Molecular Diagnosis of a Novel Coronavirus 449 (2019-nCoV) Causing an Outbreak of Pneumonia Reducing transmission of SARS-CoV-2 Reducing SARS-CoV-2 453 transmission in the UK: A behavioural science approach to identifying options for increasing 454 adherence to social distancing and shielding vulnerable people The flow physics of COVID-19 Dislocation network in additive manufactured steel breaks strength-ductility trade-off Fatigue behaviors of AISI 316L stainless steel with a 461 gradient nanostructured surface layer Design of a novel Mn-based 1 GPa duplex stainless TRIP 463 steel with 60% ductility by a reduction of austenite stability Strength and ductility of 316L austenitic stainless steel 466 strengthened by nano-scale twin bundles Influence of sigma-phase on mechanical properties and 468 corrosion resistance of duplex stainless steels The survival of Escherichia coli O157 on a range of 470 metal surfaces Survival of foodborne 472 pathogens on stainless steel surfaces and cross-contamination to foods Aerosol and Surface Stability of SARS-CoV-2 as Compared with SARS-CoV-1, 477 Small Fruits during Handling Residual Viral and Bacterial Contamination of Surfaces after Cleaning and Disinfection Stability of SARS-CoV-2 in different environmental conditions Copper 487 as an antimicrobial agent against opportunistic pathogenic and multidrug resistant 488 Enterobacter bacteria Inactivation of influenza A virus on copper versus 490 stainless steel surfaces Antifungal activity of silver nanoparticles against Candida spp Historical review of the use of silver in the treatment of burns. I. Early uses Silver nanoparticles as a new generation of antimicrobials Human Coronavirus 229E Remains Infectious on 499 Common Touch Surface Materials Silver nanoparticles are 501 broad-spectrum bactericidal and virucidal compounds Cu-bearing high-entropy alloys with excellent antiviral 505 properties Survival of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Influenza Virus on Human Skin: Importance of Hand Hygiene in Coronavirus Disease 2019 509 (COVID-19) Towards long-lasting antibacterial 511 stainless steel surfaces by combining double glow plasma silvering with active screen plasma 512 nitriding Silver coated materials for external fixation 514 devices: in vitro biocompatibility and genotoxicity Microstructure and antibacterial 516 properties of AISI 420 stainless steel implanted by copper ions Antimicrobial efficacy of a silver-519 zeolite matrix coating on stainless steel A Surface Coating that Rapidly Inactivates SARS-CoV-2 Sars-CoV-2 524 (COVID-19) inactivation capability of copper-coated touch surface fabricated by cold-spray 525 technology Surface modification of medical metals by ion 527 implantation of silver and copper Antibacterial properties 529 and corrosion resistance of AISI 420 stainless steels implanted by silver and copper ions Antimicrobial polyethylene with 532 controlled copper release An antimicrobial stainless steel containing Cu and its fabricaiton 537 method Antibacterial properties, corrosion resistance and mechanical 539 properties of Cu-modified SUS 304 stainless steel An investigation of the antibacterial ability and cytotoxicity of a novel cu-bearing 317L 543 stainless steel A novel stainless steel with 545 intensive silver nanoparticles showing superior antibacterial property High-temperature oxidation kinetics of Cu bearing carbon steel Effect of 550 copper addition on mechanical properties, and antibacterial property of 316L stainless steel 551 corrosion resistance Production of 316L stainless steel implant 554 materials by powder metallurgy and investigation of their wear properties The influence of surface condition on the localized corrosion of 557 316L stainless steel orthopaedic implants The corrosion scenario in human body: Stainless 560 steel 316L orthopaedic implants In vivo corrosion of 316L stainless-steel hip 562 implants: morphology and elemental compositions of corrosion products On the microstructures and 565 fatigue behaviors of 316L stainless steel metal injection molded with gas-and water-566 atomized powders Recognition of aerosol transmission of 568 infectious agents: a commentary Inhibition effect of silver 570 nanoparticles on herpes simplex virus 2 A new antibacterial Co-Cr-Mo-Cu alloy: Preparation, biocorrosion, 573 mechanical and antibacterial property Assessment of the Antiviral 576 Properties of Zeolites Containing Metal Ions Development and characterization of 579 porous silver-incorporated hydroxyapatite ceramic for separation and elimination of 580 microorganisms Efficacy of silver-coated medical 583 devices Antimicrobial activity and action of silver Antimicrobial Activity of Stable Silver Nanoparticles of a Certain Size Antibacterial 590 activity of large-area monolayer graphene film manipulated by charge transfer Interaction of silver nitrate with 593 readily identifiable groups: relationship to the antibacterial action of silver ions Antiviral activity of 596 silver nanoparticle/chitosan composites against H1N1 influenza A virus Does the antibacterial activity of silver nanoparticles depend 599 on the shape of the nanoparticle? A study of the gram-negative bacterium Escherichia coli, 600 Interaction of silver nitrate with readily 602 identifiable groups: relationship to the antibacterialaction of silver ions Interaction of silver nanoparticles with HIV-1 608 Survival of SARS-CoV-2 and influenza virus on the human skin: Importance of hand hygiene 609 in COVID-19 Inactivation and morphological 612 changes of avian influenza virus by copper ions Antiviral Activities of Cu2+ Ions in Viral Prevention, Replication, RNA 615 Degradation, and for Antiviral Efficacies of Lytic Virus, ROS-Mediated Virus, Copper 616 Chelation Biocidal Efficacy of Copper Alloys 618 against Pathogenic Enterococci Involves Degradation of Genomic and Plasmid DNAs Antibacterial Performance of Cu-Bearing Stainless 621 Steel against Staphylococcus aureus and Pseudomonas aeruginosa in Whole Milk Inactivation of Norovirus on Dry Copper Alloy Surfaces (i) 649 BSE image for Cu-rich precipitates of micron and submicron sizes within the SS 650 matrix; (ii) the corresponding EDX mapping of Cu element in (i); (iii) TEM HAADF 651 images of nano-sized Cu-rich precipitates within the SS matrix A) Cu ion concentration released from pure Cu and the Cu-contained SS in 656 the DMEM solution; (B) Ag ion concentrations released from pure Ag and the Ag-657 contained SS in the DMEM solution  Antiviral stainless steel inactivates 99.75% of SARS-CoV-2 virus within 3  A long-term anti-pathogen property against SARS-COV-2, H1N1 Antiviral stainless steels can be produced by existing powder metallurgy 683 method Pure Ag and Ag-contained stainless steel can not inactivate SARS-COV-2 and 685 H1N1