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1.
J Clin Pediatr Dent ; 46(3): 211-218, 2022 May 01.
Article in English | MEDLINE | ID: covidwho-2025882

ABSTRACT

OBJECTIVES: With the recent improvements in technology, the expectation of minimal invasion and maximal comfort in caries removal techniques is increasing. This study aims to examine the effectiveness of six caries removal methods in primary teeth. STUDY DESIGN: Sixty primary molars (10 teeth in each groups) were used. The groups were: Group I (Tungsten Carbide Bur), Group II (Sono abrasion), Group III (Air abrasion), Group IV (Carisolv), Group V (Er:YAG Laser), Group VI (ART). In micro-CT scanning, mineral density at the cavity floor was examined before and after caries removal. After caries removal, the patency of the dentinal tubules was examined in two teeth from each group on SEM images. Statistical analyses were performed using Kruskal-Wallis, Wilcoxon tests. RESULTS: For six different caries removal methods, tooth mineral (inorganic, total) densities at cavity floors were compared among the groups after the procedures, and no statistically significant difference was found (p>0.05). On the SEM images, it was seen that the dentinal tubules were exposed and no smear layer was formed in the Carisolv group. Significant rough surfaces were exposed in the laser group. CONCLUSION: It was observed that alternative caries removal methods are at least as effective as the traditional method in primary teeth for clinical applications.


Subject(s)
Dental Caries , Dental Cavity Preparation , Air Abrasion, Dental , Dental Caries/diagnostic imaging , Dental Caries/therapy , Dental Caries Susceptibility , Dental Cavity Preparation/methods , Dentin/diagnostic imaging , Humans , Microscopy, Electron, Scanning , Minerals , Surface Properties , Tooth, Deciduous , X-Ray Microtomography
2.
Drug Deliv ; 28(1): 856-864, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1947906

ABSTRACT

SARS-CoV-2 is a novel coronavirus that was isolated and identified for the first time in Wuhan, China in 2019. Nowadays, it is a worldwide danger and the WHO named it a pandemic. In this investigation, a functionalization post-synthesis method was used to assess the ability of an adapted SBA-15 surface as a sorbent to load the drug from an aqueous medium. Different characterization approaches were used to determine the characterization of the substance before and after functionalization such as X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), nitrogen adsorption-desorption porosimetry (Brunauer-Emmett-Teller) BET surface area analysis, and thermal gravimetric analysis (TGA). Batch adsorption testing was carried out in a single adsorption device to find the impact of multiple variables on the drug amoxicillin charge output. The following parameters were studied: 0-72 hr. contact time, 20-120 mg/l initial concentration, and 20-250 mg of NH2-SBA-15 dose. The outcomes from such experiments revealed the strong influence and behavior of the amino-functional group to increase the drug's load. Drug delivery outcomes studies found that amoxicillin loading was directly related to NH2-SBA-15 contact time and dose, but indirectly related to primary concentration. It was observed that 80% of amoxicillin was loaded while the best release test results were 1 hour and 51%.


Subject(s)
Amoxicillin/therapeutic use , COVID-19/drug therapy , Silicon Dioxide/chemistry , Amoxicillin/administration & dosage , Chemistry, Pharmaceutical , Dose-Response Relationship, Drug , Drug Delivery Systems , Humans , Microscopy, Electron, Scanning , Porosity , SARS-CoV-2 , Spectroscopy, Fourier Transform Infrared , Surface Properties , X-Ray Diffraction
3.
Viruses ; 14(2)2022 01 21.
Article in English | MEDLINE | ID: covidwho-1715755

ABSTRACT

The interaction of phages with abiotic environmental surfaces is usually an understudied field of phage ecology. In this study, we investigated the virucidal potential of different metal salts, metal and ceramic powders doped with Ag and Cu ions, and newly fabricated ceramic and metal surfaces against Phi6 bacteriophage. The new materials were fabricated by spark plasma sintering (SPS) and/or selective laser melting (SLM) techniques and had different surface free energies and infiltration features. We show that inactivation of Phi6 in solutions with Ag and Cu ions can be as effective as inactivation by pH, temperature, or UV. Adding powder to Ag and Cu ion solutions decreased their virucidal effect. The newly fabricated ceramic and metal surfaces showed very good virucidal activity. In particular, 45%TiO2 + 5%Ag + 45%ZrO2 + 5%Cu, in addition to virus adhesion, showed virucidal and infiltration properties. The results indicate that more than 99.99% of viruses deposited on the new ceramic surface were inactivated or irreversibly attached to it.


Subject(s)
Bacteriophage phi 6/drug effects , Copper/pharmacology , Silver/pharmacology , Bacteriophage phi 6/growth & development , Bacteriophage phi 6/physiology , Ceramics/chemistry , Copper/chemistry , Hydrogen-Ion Concentration , Powders/chemistry , Silver/chemistry , Surface Properties , Temperature
4.
ACS Appl Mater Interfaces ; 14(9): 11068-11077, 2022 Mar 09.
Article in English | MEDLINE | ID: covidwho-1713108

ABSTRACT

Amidst the COVID-19 pandemic, it is evident that viral spread is mediated through several different transmission pathways. Reduction of these transmission pathways is urgently needed to control the spread of viruses between infected and susceptible individuals. Herein, we report the use of pathogen-repellent plastic wraps (RepelWrap) with engineered surface structures at multiple length scales (nanoscale to microscale) as a means of reducing the indirect contact transmission of viruses through fomites. To quantify viral repellency, we developed a touch-based viral quantification assay to mimic the interaction of a contaminated human touch with a surface through the modification of traditional viral quantification methods (viral plaque and TCID50 assays). These studies demonstrate that RepelWrap reduced contamination with an enveloped DNA virus as well as the human coronavirus 229E (HuCoV-229E) by more than 4 log 10 (>99.99%) compared to a standard commercially available polyethylene plastic wrap. In addition, RepelWrap maintained its repellent properties after repeated 300 touches and did not show an accumulation in viral titer after multiple contacts with contaminated surfaces, while increases were seen on other commonly used surfaces. These findings show the potential use of repellent surfaces in reducing viral contamination on surfaces, which could, in turn, reduce the surface-based spread and transmission.


Subject(s)
COVID-19/prevention & control , Coronavirus 229E, Human/growth & development , Equipment Contamination/prevention & control , Infection Control/instrumentation , Plastics/chemistry , COVID-19/transmission , COVID-19/virology , Humans , Infection Control/methods , SARS-CoV-2/growth & development , Surface Properties
5.
Int J Mol Sci ; 23(3)2022 Jan 21.
Article in English | MEDLINE | ID: covidwho-1650511

ABSTRACT

International interest in metal-based antimicrobial coatings to control the spread of bacteria, fungi, and viruses via high contact human touch surfaces are growing at an exponential rate. This interest recently reached an all-time high with the outbreak of the deadly COVID-19 disease, which has already claimed the lives of more than 5 million people worldwide. This global pandemic has highlighted the major role that antimicrobial coatings can play in controlling the spread of deadly viruses such as SARS-CoV-2 and scientists and engineers are now working harder than ever to develop the next generation of antimicrobial materials. This article begins with a review of three discrete microorganism-killing phenomena of contact-killing surfaces, nanoprotrusions, and superhydrophobic surfaces. The antimicrobial properties of metals such as copper (Cu), silver (Ag), and zinc (Zn) are reviewed along with the effects of combining them with titanium dioxide (TiO2) to create a binary or ternary contact-killing surface coatings. The self-cleaning and bacterial resistance of purely structural superhydrophobic surfaces and the potential of physical surface nanoprotrusions to damage microbial cells are then considered. The article then gives a detailed discussion on recent advances in attempting to combine these individual phenomena to create super-antimicrobial metal-based coatings with binary or ternary killing potential against a broad range of microorganisms, including SARS-CoV-2, for high-touch surface applications such as hand rails, door plates, and water fittings on public transport and in healthcare, care home and leisure settings as well as personal protective equipment commonly used in hospitals and in the current COVID-19 pandemic.


Subject(s)
Anti-Infective Agents/pharmacology , COVID-19/prevention & control , Coated Materials, Biocompatible/pharmacology , Metals/chemistry , Touch , Animals , Anti-Infective Agents/chemical synthesis , Anti-Infective Agents/chemistry , COVID-19/transmission , Coated Materials, Biocompatible/chemical synthesis , Coated Materials, Biocompatible/chemistry , Humans , Pandemics , Personal Protective Equipment/microbiology , Personal Protective Equipment/virology , SARS-CoV-2/drug effects , Surface Properties , Viruses/drug effects
6.
J Nanobiotechnology ; 19(1): 458, 2021 Dec 28.
Article in English | MEDLINE | ID: covidwho-1577211

ABSTRACT

Bio-inspired Topographically Mediated Surfaces (TMSs) based on high aspect ratio nanostructures have recently been attracting significant attention due to their pronounced antimicrobial properties by mechanically disrupting cellular processes. However, scalability of such surfaces is often greatly limited, as most of them rely on micro/nanoscale fabrication techniques. In this report, a cost-effective, scalable, and versatile approach of utilizing diamond nanotechnology for producing TMSs, and using them for limiting the spread of emerging infectious diseases, is introduced. Specifically, diamond-based nanostructured coatings are synthesized in a single-step fabrication process with a densely packed, needle- or spike-like morphology. The antimicrobial proprieties of the diamond nanospike surface are qualitatively and quantitatively analyzed and compared to other surfaces including copper, silicon, and even other diamond surfaces without the nanostructuring. This surface is found to have superior biocidal activity, which is confirmed via scanning electron microscopy images showing definite and widespread destruction of E. coli cells on the diamond nanospike surface. Consistent antimicrobial behavior is also observed on a sample prepared seven years prior to testing date.


Subject(s)
Anti-Bacterial Agents/chemistry , Coated Materials, Biocompatible/chemistry , Diamond/chemistry , Nanostructures/chemistry , Anti-Bacterial Agents/pharmacology , Coated Materials, Biocompatible/pharmacology , Copper/chemistry , Copper/pharmacology , Diamond/pharmacology , Escherichia coli/drug effects , Escherichia coli/growth & development , Nanostructures/ultrastructure , Nanotechnology , Surface Properties
7.
Sci Rep ; 12(1): 1416, 2022 01 26.
Article in English | MEDLINE | ID: covidwho-1655626

ABSTRACT

The control of the COVID-19 pandemic in the UK has necessitated restrictions on amateur and professional sports due to the perceived infection risk to competitors, via direct person to person transmission, or possibly via the surfaces of sports equipment. The sharing of sports equipment such as tennis balls was therefore banned by some sport's governing bodies. We sought to investigate the potential of sporting equipment as transmission vectors of SARS-CoV-2. Ten different types of sporting equipment, including balls from common sports, were inoculated with 40 µl droplets containing clinically relevant concentrations of live SARS-CoV-2 virus. Materials were then swabbed at time points relevant to sports (1, 5, 15, 30, 90 min). The amount of live SARS-CoV-2 recovered at each time point was enumerated using viral plaque assays, and viral decay and half-life was estimated through fitting linear models to log transformed data from each material. At one minute, SARS-CoV-2 virus was recovered in only seven of the ten types of equipment with the low dose inoculum, one at five minutes and none at 15 min. Retrievable virus dropped significantly for all materials tested using the high dose inoculum with mean recovery of virus falling to 0.74% at 1 min, 0.39% at 15 min and 0.003% at 90 min. Viral recovery, predicted decay, and half-life varied between materials with porous surfaces limiting virus transmission. This study shows that there is an exponential reduction in SARS-CoV-2 recoverable from a range of sports equipment after a short time period, and virus is less transferrable from materials such as a tennis ball, red cricket ball and cricket glove. Given this rapid loss of viral load and the fact that transmission requires a significant inoculum to be transferred from equipment to the mucous membranes of another individual it seems unlikely that sports equipment is a major cause for transmission of SARS-CoV-2. These findings have important policy implications in the context of the pandemic and may promote other infection control measures in sports to reduce the risk of SARS-CoV-2 transmission and urge sports equipment manufacturers to identify surfaces that may or may not be likely to retain transferable virus.


Subject(s)
COVID-19/transmission , SARS-CoV-2/physiology , COVID-19/virology , Half-Life , Humans , Linear Models , SARS-CoV-2/isolation & purification , Sports Equipment , Surface Properties
8.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Article in English | MEDLINE | ID: covidwho-1642082

ABSTRACT

The phase state of respiratory aerosols and droplets has been linked to the humidity-dependent survival of pathogens such as SARS-CoV-2. To inform strategies to mitigate the spread of infectious disease, it is thus necessary to understand the humidity-dependent phase changes associated with the particles in which pathogens are suspended. Here, we study phase changes of levitated aerosols and droplets composed of model respiratory compounds (salt and protein) and growth media (organic-inorganic mixtures commonly used in studies of pathogen survival) with decreasing relative humidity (RH). Efflorescence was suppressed in many particle compositions and thus unlikely to fully account for the humidity-dependent survival of viruses. Rather, we identify organic-based, semisolid phase states that form under equilibrium conditions at intermediate RH (45 to 80%). A higher-protein content causes particles to exist in a semisolid state under a wider range of RH conditions. Diffusion and, thus, disinfection kinetics are expected to be inhibited in these semisolid states. These observations suggest that organic-based, semisolid states are an important consideration to account for the recovery of virus viability at low RH observed in previous studies. We propose a mechanism in which the semisolid phase shields pathogens from inactivation by hindering the diffusion of solutes. This suggests that the exogenous lifetime of pathogens will depend, in part, on the organic composition of the carrier respiratory particle and thus its origin in the respiratory tract. Furthermore, this work highlights the importance of accounting for spatial heterogeneities and time-dependent changes in the properties of aerosols and droplets undergoing evaporation in studies of pathogen viability.


Subject(s)
Calcium Chloride/chemistry , Models, Chemical , SARS-CoV-2/chemistry , Serum Albumin/chemistry , Sodium Chloride/chemistry , COVID-19/virology , Diffusion , Disinfection/methods , Humans , Humidity , Kinetics , Microbial Viability , Phase Transition , Surface Properties
9.
Adv Mater ; 34(8): e2107892, 2022 Feb.
Article in English | MEDLINE | ID: covidwho-1634021

ABSTRACT

Surface chemistry critically affects the diagnostic performance of biosensors. An ideal sensor surface should be resistant to nonspecific protein adsorption, yet be conducive to analytical responses. Here a new polymeric material, zwitterionic polypyrrole (ZiPPy), is reported to produce optimal surface condition for biosensing electrodes. ZiPPy combines two unique advantages: the zwitterionic function that efficiently hydrates electrode surface, hindering nonspecific binding of hydrophobic proteins; and the pyrrole backbone, which enables rapid (<7 min), controlled deposition of ZiPPy through electropolymerization. ZiPPy-coated electrodes show lower electrochemical impedance and less nonspecific protein adsorption (low fouling), outperforming bare and polypyrrole-coated electrodes. Moreover, affinity ligands for target biomarkers can be immobilized together with ZiPPy in a single-step electropolymerization. ZiPPy-coated electrodes are developed with specificity for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The prepared sensor detects SARS-CoV-2 antibodies in human saliva down to 50 ng mL-1 , without the need for sample purification or secondary labeling.


Subject(s)
Antibodies, Viral/analysis , Biosensing Techniques/methods , COVID-19/diagnosis , Polymers/chemistry , Pyrroles/chemistry , Biosensing Techniques/instrumentation , COVID-19/virology , Electrochemical Techniques , Electrodes , Electroplating , Gold/chemistry , Humans , Limit of Detection , SARS-CoV-2/immunology , SARS-CoV-2/isolation & purification , Saliva/metabolism , Surface Properties
10.
PLoS One ; 16(12): e0261441, 2021.
Article in English | MEDLINE | ID: covidwho-1581741

ABSTRACT

Estimating the contact angle of a virus infected saliva droplet is seen to be an important area of research as it presents an idea about the drying time of the respective droplet and in turn of the growth of the underlying pandemic. In this paper we extend the data presented by Balusamy, Banerjee and Sahu ["Lifetime of sessile saliva droplets in the context of SARS-CoV-2," Int. J. Heat Mass Transf. 123, 105178 (2021)], where the contact angles are fitted using a newly proposed half-circular wrapped-exponential model, and a sequential confidence interval estimation approach is established which largely reduces both time and cost with regards to data collection.


Subject(s)
COVID-19/diagnosis , Saliva/virology , Specimen Handling/methods , COVID-19/immunology , Diagnostic Tests, Routine , Humans , Models, Theoretical , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity , Saliva/chemistry , Surface Properties
11.
Acc Chem Res ; 54(24): 4508-4517, 2021 12 21.
Article in English | MEDLINE | ID: covidwho-1556900

ABSTRACT

Self-disinfecting surfaces are a current pressing need for public health and safety in view of the current COVID-19 pandemic, where the keenly felt worldwide repercussions have highlighted the importance of infection control, frequent disinfection, and proper hygiene. Because of its potential impact upon real-world translation into downstream applications, there has been much research interest in multiple disciplines such as materials science, chemistry, biology, and engineering. Various antimicrobial technologies have been developed and currently applied on surfaces in public spaces, such as elevator buttons and escalator handrails. These technologies are mainly based on conventional methods of grafting quaternary ammonium salts (QACs) such as benzalkonium chloride or the immobilization of metal species of silver or copper. However, neither the long-term efficacy nor the fast-killing properties have been proven, and the future repercussions from extended use, such as environmental hazards and the induction of MDR development, is unknown. Nanostructured surfaces with excellent antimicrobial activities have been claimed to be the next generation of self-disinfecting surfaces with various promising applications and passive antimicrobial mechanisms, without the potential repercussions of active ingredient overuse. In this Account, we briefly introduce the concept of mechanobactericidal action realized by these nanostructured surfaces first discovered on cicada wings. The elimination of microbes on the surface was actualized by the physical rupture of the microbe cell wall by nanoprotusions, without any involvement of chemical species. By mimicking the physical features of naturally occurring biocidal surfaces, the fabrication of nanostructures on various substrates such as titania, silicon, and polymers has been well described. Observations of the dependence of their antimicrobial efficacy on physical characteristics such as height, density, and rigidity have also been documented. However, the complex fabrication of such nanostructures remains the main drawback preventing its widespread application. We outline our efforts in fabricating a series of zinc-based nanostructured materials with facile and generally applicable wet chemistry methods, including nanodaggered zeolitic imidazolate frameworks (ZIF-L) and ZnO nanoneedles. In our investigations, we discovered that there were additional modes of action that contributed to the excellent biocidal activities of our materials. The impact of surface chemistry and charge was partially responsible for the selectivity and efficacy of ZIF-L-coated surfaces, where the positively charged surfaces were able to attract and adhere negatively charged bacteria to the surface. The combination of semiconductor ZnO nanoneedles on electron-donating substrates allowed for the generation of reactive oxygen species (ROS), realizing the remote killing of bacteria unadhered to the nanostructured surface. Additionally, we demonstrate several real-life applications of the synthesized materials, underscoring the importance of materials development suited for scale-up and eventual translation to potential applications and commercial end products.


Subject(s)
Anti-Infective Agents , COVID-19 , Nanostructures , Animals , Anti-Infective Agents/pharmacology , Humans , Pandemics , SARS-CoV-2 , Surface Properties
12.
Int J Mol Sci ; 22(23)2021 Nov 24.
Article in English | MEDLINE | ID: covidwho-1542582

ABSTRACT

COVID-19 pandemic and associated supply-chain disruptions emphasise the requirement for antimicrobial materials for on-demand manufacturing. Besides aerosol transmission, SARS-CoV-2 is also propagated through contact with virus-contaminated surfaces. As such, the development of effective biofunctional materials that can inactivate SARS-CoV-2 is critical for pandemic preparedness. Such materials will enable the rational development of antiviral devices with prolonged serviceability, reducing the environmental burden of disposable alternatives. This research reveals the novel use of Laser Powder Bed Fusion (LPBF) to 3D print porous Cobalt-Chromium-Molybdenum (Co-Cr-Mo) superalloy with potent antiviral activity (100% viral inactivation in 30 min). The porous material was rationally conceived using a multi-objective surrogate model featuring track thickness (tt) and pore diameter (ϕd) as responses. The regression analysis found the most significant parameters for Co-Cr-Mo track formation to be the interaction effects of scanning rate (Vs) and laser power (Pl) in the order PlVs>Vs>Pl. Contrastively, the pore diameter was found to be primarily driven by the hatch spacing (Sh). The study is the first to demonstrate the superior antiviral properties of 3D printed Co-Cr-Mo superalloy against an enveloped virus used as biosafe viral model of SARS-CoV-2. The material significantly outperforms the viral inactivation time of other broadly used antiviral metals such as copper and silver, as the material's viral inactivation time was from 5 h to 30 min. As such, the study goes beyond the current state-of-the-art in antiviral alloys to provide extra protection to combat the SARS-CoV-2 viral spread. The evolving nature of the COVID-19 pandemic brings new and unpredictable challenges where on-demand 3D printing of antiviral materials can achieve rapid solutions while reducing the environmental impact of disposable devices.


Subject(s)
Antiviral Agents/pharmacology , Chromium/pharmacology , Cobalt/pharmacology , Molybdenum/pharmacology , Printing, Three-Dimensional , Alloys , COVID-19 , Humans , Porosity , SARS-CoV-2/drug effects , Surface Properties , Virus Inactivation/drug effects
13.
Biomolecules ; 11(11)2021 11 17.
Article in English | MEDLINE | ID: covidwho-1523862

ABSTRACT

Metal-organic frameworks (MOFs) have been widely used as porous nanomaterials for different applications ranging from industrial to biomedicals. An unpredictable one-pot method is introduced to synthesize NH2-MIL-53 assisted by high-gravity in a greener media for the first time. Then, porphyrins were deployed to adorn the surface of MOF to increase the sensitivity of the prepared nanocomposite to the genetic materials and in-situ cellular protein structures. The hydrogen bond formation between genetic domains and the porphyrin' nitrogen as well as the surface hydroxyl groups is equally probable and could be considered a milestone in chemical physics and physical chemistry for biomedical applications. In this context, the role of incorporating different forms of porphyrins, their relationship with the final surface morphology, and their drug/gene loading efficiency were investigated to provide a predictable pattern in regard to the previous works. The conceptual phenomenon was optimized to increase the interactions between the biomolecules and the substrate by reaching the limit of detection to 10 pM for the Anti-cas9 protein, 20 pM for the single-stranded DNA (ssDNA), below 10 pM for the single guide RNA (sgRNA) and also around 10 nM for recombinant SARS-CoV-2 spike antigen. Also, the MTT assay showed acceptable relative cell viability of more than 85% in most cases, even by increasing the dose of the prepared nanostructures.


Subject(s)
COVID-19/diagnosis , Metal-Organic Frameworks/chemistry , Porphyrins/chemistry , Animals , COVID-19 Testing , CRISPR-Cas Systems , DNA, Single-Stranded , HEK293 Cells , HeLa Cells , Hep G2 Cells , Humans , Hydrogen Bonding , Limit of Detection , Nanocomposites , Nanostructures , Nitrogen/chemistry , PC12 Cells , Porosity , RNA, Guide , RNA, Viral/metabolism , Rats , SARS-CoV-2 , Sensitivity and Specificity , Surface Properties
14.
ACS Appl Mater Interfaces ; 13(46): 54706-54714, 2021 Nov 24.
Article in English | MEDLINE | ID: covidwho-1514382

ABSTRACT

Antimicrobial coatings are one method to reduce the spread of microbial diseases. Transparent coatings preserve the visual properties of surfaces and are strictly necessary for applications such as antimicrobial cell phone screens. This work describes transparent coatings that inactivate microbes within minutes. The coatings are based on a polydopamine (PDA) adhesive, which has the useful property that the monomer can be sprayed, and then the monomer polymerizes in a conformal film at room temperature. Two coatings are described (1) a coating where PDA is deposited first and then a thin layer of copper is grown on the PDA by electroless deposition (PDA/Cu) and (2) a coating where a suspension of Cu2O particles in a PDA solution is deposited in a single step (PDA/Cu2O). In the second coating, PDA menisci bind Cu2O particles to the solid surface. Both coatings are transparent and are highly efficient in inactivating microbes. PDA/Cu kills >99.99% of Pseudomonas aeruginosa and 99.18% of methicillin-resistant Staphylococcus aureus (MRSA) in only 10 min and inactivates 99.98% of SARS-CoV-2 virus in 1 h. PDA/Cu2O kills 99.94% of P. aeruginosa and 96.82% of MRSA within 10 min and inactivates 99.88% of SARS-CoV-2 in 1 h.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antiviral Agents/pharmacology , Drug Resistance, Microbial/drug effects , SARS-CoV-2/drug effects , COVID-19/virology , Humans , Methicillin-Resistant Staphylococcus aureus/drug effects , Pseudomonas aeruginosa/drug effects , Surface Properties
15.
Int J Mol Sci ; 22(21)2021 Nov 01.
Article in English | MEDLINE | ID: covidwho-1512379

ABSTRACT

The research presented herein follows an urgent global need for the development of novel surface engineering techniques that would allow the fabrication of next-generation cardiovascular stents, which would drastically reduce cardiovascular diseases (CVD). The combination of hydrothermal treatment (HT) and treatment with highly reactive oxygen plasma (P) allowed for the formation of an oxygen-rich nanostructured surface. The morphology, surface roughness, chemical composition and wettability of the newly prepared oxide layer on the Ti substrate were characterized by scanning electron microscopy (SEM) with energy-dispersive X-ray analysis (EDX), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and water contact angle (WCA) analysis. The alteration of surface characteristics influenced the material's bio-performance; platelet aggregation and activation was reduced on surfaces treated by hydrothermal treatment, as well as after plasma treatment. Moreover, it was shown that surfaces treated by both treatment procedures (HT and P) promoted the adhesion and proliferation of vascular endothelial cells, while at the same time inhibiting the adhesion and proliferation of vascular smooth muscle cells. The combination of both techniques presents a novel approach for the fabrication of vascular implants, with superior characteristics.


Subject(s)
Endothelial Cells/cytology , Muscle, Smooth, Vascular/cytology , Plasma/chemistry , Titanium/chemistry , Cell Adhesion , Cell Line , Cell Proliferation , Humans , Microscopy, Atomic Force , Microscopy, Electron, Scanning , Nanostructures , Particle Size , Stents , Surface Properties , Wettability
16.
Eur Rev Med Pharmacol Sci ; 25(20): 6378-6385, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1503069

ABSTRACT

OBJECTIVE: The outbreak of SARS-CoV-2 in 2020 has become the world's largest public health event, causing global attention and concern. Despite national efforts to control this emerging infectious disease, it still cannot be contained. China, which reported the disease early, was able to control the outbreak quickly, but there is the problem of imported infections abroad. This review aims to summarize SARS-CoV-2 detected on the outer packaging of imported cold chain food and lead to the transmission of novel coronavirus. MATERIALS AND METHODS: We reviewed information on SARS-COV-2 detected on the outer packaging of imported cold chain food and relevant literature.  We searched the following databases: PubMed, Web of Science, EMBASE and CNKI. search terms were "2019 nCoV", "SARS-CoV-2", "COVID-19", "cold-chain", "item surface", "spread", "people". RESULTS: We found that SARS-CoV-2 survives on the surface of cold-chain food for a long period of time and these active viruses can be transmitted to humans. CONCLUSIONS: We believe that while strictly preventing and controlling the importation of infected patients, we should strengthen the management of imported cold-chain food and its workers to prevent the transmission of SARS-CoV-2 to humans on the surface of cold-chain food objects.


Subject(s)
Food Packaging , Food Preservation , Refrigeration , SARS-CoV-2/isolation & purification , China , Humans , Surface Properties
17.
Langmuir ; 37(41): 12089-12097, 2021 10 19.
Article in English | MEDLINE | ID: covidwho-1450265

ABSTRACT

The COVID-19 pandemic has claimed millions of lives worldwide, sickened many more, and has resulted in severe socioeconomic consequences. As society returns to normal, understanding the spread and persistence of SARS CoV-2 on commonplace surfaces can help to mitigate future outbreaks of coronaviruses and other pathogens. We hypothesize that such an understanding can be aided by studying the binding and interaction of viral proteins with nonbiological surfaces. Here, we propose a methodology for investigating the adhesion of the SARS CoV-2 spike glycoprotein on common inorganic surfaces such as aluminum, copper, iron, silica, and ceria oxides as well as metallic gold. Quantitative adhesion was obtained from the analysis of measured forces at the nanoscale using an atomic force microscope operated under ambient conditions. Without imposing further constraints on the measurement conditions, our preliminary findings suggest that spike glycoproteins interact with similar adhesion forces across the majority of the metal oxides tested with the exception to gold, for which attraction forces ∼10 times stronger than all other materials studied were observed. Ferritin, which was used as a reference protein, was found to exhibit similar adhesion forces as SARS CoV-2 spike protein. This study results show that glycoprotein adhesion forces for similar ambient humidity, tip shape, and contact surface are nonspecific to the properties of metal oxide surfaces, which are expected to be covered by a thin water film. The findings suggest that under ambient conditions, glycoprotein adhesion to metal oxides is primarily controlled by the water capillary forces, and they depend on the surface tension of the liquid water. We discuss further strategies warranted to decipher the intricate nanoscale forces for improved quantification of the adhesion.


Subject(s)
COVID-19 , Humans , Microscopy, Atomic Force , Pandemics , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Surface Properties
18.
PLoS One ; 16(9): e0257434, 2021.
Article in English | MEDLINE | ID: covidwho-1443838

ABSTRACT

Although research has shown that the COVID-19 disease is most likely caused by airborne transmission of the SARS-CoV-2 virus, disinfection of potentially contaminated surfaces is also recommended to limit the spread of the disease. Use of electrostatic sprayers (ESS) and foggers to rapidly apply disinfectants over large areas or to complex surfaces has emerged with the COVID-19 pandemic. ESSs are designed to impart an electrostatic charge to the spray droplets with the goal of increasing deposition of the droplets onto surfaces, thereby promoting more efficient use of the disinfectant. The purpose of this research was to evaluate several spray parameters for different types of sprayers and foggers, as they relate to the application of disinfectants. Some of the parameters evaluated included the spray droplet size distribution, the electrostatic charge, the ability of the spray to wrap around objects, and the loss of disinfectant chemical active ingredient due to the spray process. The results show that most of the devices evaluated for droplet size distribution had an average volume median diameter ≥ 40 microns, and that four out of the six ESS tested for charge/mass produced sprays of at least 0.1 mC/kg. A minimal wrap-around effect of the spray deposition onto a cylindrical object was observed. The loss of disinfectant active ingredient to the air due to spraying was minimal for the two disinfectants tested, and concurrently, the active ingredient concentrations of the liquid disinfectants sprayed and collected 3 feet (1 meter) away from the spray nozzle do not decrease.


Subject(s)
COVID-19/prevention & control , Disinfectants/administration & dosage , Disinfection/instrumentation , Disinfectants/pharmacology , Disinfection/methods , Equipment Design , Humans , SARS-CoV-2/drug effects , Static Electricity , Surface Properties/drug effects
19.
ChemMedChem ; 16(23): 3553-3558, 2021 12 06.
Article in English | MEDLINE | ID: covidwho-1437037

ABSTRACT

In the search for a fast contact-killing antimicrobial surface to break the transmission pathway of lethal pathogens, nanostructured copper surfaces were found to exhibit the desired antimicrobial properties. Compared with plain copper, these nanostructured copper surfaces with Cu(OH)2 nano-sword or CuO nano-foam were found to completely eliminate pathogens at a fast rate, including clinically isolated drug resistant species. Additionally these nanostructured copper surfaces demonstrated potential antiviral properties when assessed against bacteriophages, as a viral surrogate, and murine hepatitis virus, a surrogate for SARS-CoV-2. The multiple modes of killing, physical killing and copper ion mediated killing contribute to the superior and fast kinetics of antimicrobial action against common microbes, and ESKAPE pathogens. Prototypes for air and water cleaning with current nanostructured copper surface have also been demonstrated.


Subject(s)
Bacteria/drug effects , Copper/chemistry , Hepatitis Viruses/drug effects , Hydroxides/chemistry , Nanostructures/toxicity , SARS-CoV-2/drug effects , Animals , Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Copper/pharmacology , Drug Resistance, Bacterial/drug effects , Mice , Microbial Sensitivity Tests , Nanostructures/chemistry , Surface Properties
20.
Niger J Clin Pract ; 24(9): 1313-1320, 2021 Sep.
Article in English | MEDLINE | ID: covidwho-1417243

ABSTRACT

BACKGROUND: Tuberculosis (TB) is a communicable disease as well as an airborne disease. Mycobacterium tuberculosis (MTB) could survive on dental materials shipped to dental laboratories. AIMS: The aim of this study was to determine the number of bacilli held on the prosthetic material and the effect of chemical disinfection agents on various prosthetic materials that were shipped to dental laboratory of TB patient. MATERIALS AND METHODS: The study consisted of three study groups, and a control group. 10 mm x 2 mm disc-shaped (n = 18 for each group, n = 72 in total) nickel-chromium alloy (Ni-Cr), polymethylmethacrylate (PMMA), and dental ceramic (DC) samples were prepared. After exposure to MTB 24 hours in a 37°C incubator, six samples for each group (PMMA), Ni-Cr alloy and a control group DC samples) were exposed to three disinfectants; 10 minutes into 2% glutaraldehyde, 10 minutes into 5% sodium hypochlorite, and 1 minute into alcohol-based disinfectant after vortexed in distilled water. Colony forming units (CFU/ml) were calculated per milliliters. Two-way ANOVA statistical analysis method was used, and a P value less than 0.05 was considered as significant. RESULTS: The bacteria count for six Ni-Cr alloy disc-shaped specimens were recorded as 40, 10, 8, 6, 5, and 4 CFU/ml, respectively. Intensity of the colonies were found to be lower in other groups. 5 CFU/ml were detected on a single PMMA sample in the control group, and 40 CFU/ml were detected on one of the dental ceramic sample. No MTB uptake was observed on any sample in the 2% glutaraldehyde and 5% NaOCl disinfectant study groups. In alcohol-based disinfectant group, 1 CFU/ml was observed on Ni-Cr alloy sample. The effect of prosthetic materials used in this experimental study were not statistically significant on the CFU (p = 0.293). However, the disinfectants use was statistically significant on the number of colonies (p = 0.004). CONCLUSION: NaOCl and glutaraldehyde appeared to be more effective than alcohol-based disinfectant in removing MTB from Ni-Cr alloy, PMMA and dental ceramic surfaces.


Subject(s)
COVID-19 , Disinfectants , Tuberculosis , Disinfectants/pharmacology , Humans , SARS-CoV-2 , Surface Properties
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