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1.
Molecules ; 27(20)2022 Oct 13.
Article in English | MEDLINE | ID: covidwho-2071651

ABSTRACT

Since the outbreak of COVID-19, face masks have been introduced in the complex strategy of infection prevention and control. Face masks consist of plastic polymers and additives such as phthalates. The aim of this study was to evaluate the migration of microplastics (MP) and phthalates from face masks to water. Four types of masks including FFP2 masks and surgical were studied. Masks were first characterized to determine the different layers and the material used for their fabrication. Then, masks were cut into 20 pieces of 0.5 cm2, including all their layers, placed in water, and the migration of MP and phthalates was evaluated according to the conditions stated in EU Regulation No 10/2011 on plastic materials and articles intended to come into contact with food. For MP, the morphological analysis (shape, dimension, particle count) was performed using a stereomicroscope, while the identification of both masks and MP released was conducted using µ-Fourier-transform infrared spectroscopy (µ-FT-IR). Migration of phthalates was assessed by ultra-high-performance liquid chromatography coupled to triple quadrupole mass spectrometer (UPLC-MS/MS). Face masks analyzed in the present study were made of atactic polypropylene (PP) as stated by the manufacturer. The µ-FT-IR confirmed that PP and polyamide (PA) were released as fragments, while both PP and polyester (PES) were released as fibers. In addition, 4 phthalates were identified at concentrations between 2.34 and 21.0 µg/mask. This study shows that the migration study can be applied to evaluate the potential release of MP and phthalates from face masks to water and could give a hint for the potential impact of their incorrect disposal on the aquatic resources.


Subject(s)
COVID-19 , Microplastics , Humans , Plastics/chemistry , Masks , Water , Spectroscopy, Fourier Transform Infrared , Polypropylenes/analysis , Nylons , Chromatography, Liquid , COVID-19/epidemiology , COVID-19/prevention & control , Tandem Mass Spectrometry , Polyesters/analysis
2.
Microbiol Spectr ; 10(5): e0055022, 2022 Oct 26.
Article in English | MEDLINE | ID: covidwho-2068501

ABSTRACT

Iodine-containing systems show broad antiseptic properties that can be an invaluable tool in controlling infections in humans and animals. Here, we describe the first proof-of-concept studies on biocidal active polyamide- and polyurethane-iodine complexes that are produced in situ directly during the fabrication and/or polymerization process at laboratory and commercially relevant scales. These polymer-iodine materials are active against a broad range of microorganisms, including bacteria and fungi. It is suggested that the ease of manufacture and subsequent commercialization make said systems especially suited for applications as base materials for medical devices to reduce infection risks and control the spread of pathogens. IMPORTANCE Infectious diseases are of mounting medical and public concern. A major contributor to this trend is the proliferation of medical implants, which are inherently vulnerable to microbial contamination and the subsequent onset of hospital-acquired infections. Moreover, implant-associated infections in humans are often difficult to diagnose and treat and are associated with substantial health care costs. Here, we present the development of biocidal active polyamide- and polyurethane-iodine complexes that are generated in situ during fabrication. We show that the excellent antiseptic properties of water-soluble povidone-iodine can be similarly realized in water-insoluble engineering plastics, specifically polyamide- and polyurethane-iodine. These complexes have inherent biocidal activity against major pathogenic bacteria and fungi.


Subject(s)
Anti-Infective Agents, Local , Iodine , Animals , Humans , Povidone-Iodine , Iodine/pharmacology , Polymers/pharmacology , Polyurethanes , Nylons , Bacteria , Water
3.
Int J Mol Sci ; 23(19)2022 Sep 29.
Article in English | MEDLINE | ID: covidwho-2066129

ABSTRACT

Topoisomerases are essential enzymes that recognize and modify the topology of DNA to allow DNA replication and transcription to take place. Topoisomerases are divided into type I topoisomerases, that cleave one DNA strand to modify DNA topology, and type II, that cleave both DNA strands. Topoisomerases normally rapidly religate cleaved-DNA once the topology has been modified. Topoisomerases do not recognize specific DNA sequences, but actively cleave positively supercoiled DNA ahead of transcription bubbles or replication forks, and negative supercoils (or precatenanes) behind, thus allowing the unwinding of the DNA-helix to proceed (during both transcription and replication). Drugs that stabilize DNA-cleavage complexes with topoisomerases produce cytotoxic DNA damage and kill fast-dividing cells; they are widely used in cancer chemotherapy. Oligonucleotide-recognizing topoisomerase inhibitors (OTIs) have given drugs that stabilize DNA-cleavage complexes specificity by linking them to either: (i) DNA duplex recognizing triplex forming oligonucleotide (TFO-OTIs) or DNA duplex recognizing pyrrole-imidazole-polyamides (PIP-OTIs) (ii) or by conventional Watson-Crick base pairing (WC-OTIs). This converts compounds from indiscriminate DNA-damaging drugs to highly specific targeted DNA-cleaving OTIs. Herein we propose simple strategies to enable DNA-duplex strand invasion of WC-OTIs giving strand-invading SI-OTIs. This will make SI-OTIs similar to the guide RNAs of CRISPR/Cas9 nuclease bacterial immune systems. However, an important difference between OTIs and CRISPR/Cas9, is that OTIs do not require the introduction of foreign proteins into cells. Recent successful oligonucleotide therapeutics for neurodegenerative diseases suggest that OTIs can be developed to be highly specific gene editing agents for DNA lesions that cause neurodegenerative diseases.


Subject(s)
Neurodegenerative Diseases , Oligonucleotides , DNA/metabolism , DNA Topoisomerases, Type I/genetics , DNA Topoisomerases, Type I/metabolism , DNA Topoisomerases, Type II/metabolism , DNA, Superhelical , Humans , Imidazoles , Neurodegenerative Diseases/drug therapy , Neurodegenerative Diseases/genetics , Nylons , Oligonucleotides/chemistry , Pyrroles , Topoisomerase I Inhibitors/pharmacology , Topoisomerase II Inhibitors , Topoisomerase Inhibitors/pharmacology , Topoisomerase Inhibitors/therapeutic use
4.
Chemosphere ; 309(Pt 1): 136748, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-2060531

ABSTRACT

The fight against the COVID-19 epidemic significantly raises the global demand for personal protective equipment, especially disposable face masks (DFMs). The discarded DFMs may become a potential source of microplastics (MPs), which has attracted much attention. In this work, we identified the detailed source of MPs released from DFMs with laser direct infrared spectroscopy. Polypropylene (PP) and polyurethane (PU) accounted for 24.5% and 57.1% of released MPs, respectively. The melt-blown fabric was a dominant MPs source, however, previous studies underestimated the contribution of mask rope. The captured polyethylene terephthalate (PET), polyamide (PA), polyethylene (PE), and polystyrene (PS) in airborne only shared 18.4% of released MPs. To deepen the understanding of MPs release from medical mask into the aquatic environment, we investigated the effects of environmental factors on MPs release. Based on regression analysis, the effects of temperature, incubation time, and wearing time significantly affect the release of MPs. Besides, acidity, alkalinity, sodium chloride, and humic acid also contributed to the MPs release through corroding, swelling, or repulsion of fibers. Based on the exposure of medical mask to simulated environments, the number of released MPs followed the order: seawater > simulated gut-fluid > freshwater > pure water. Considering the risk of MPs released from DFMs to the environment, we innovatively established a novel flotation removal system combined with cocoamidopropyl betaine, achieving 86% removal efficiency of MPs in water. This work shed the light on the MPs release from DFMs and proposed a removal strategy for the control of MPs pollution.


Subject(s)
COVID-19 , Water Pollutants, Chemical , Humans , Microplastics , Plastics , Polystyrenes/chemistry , Polypropylenes , Polyethylene Terephthalates , Humic Substances , Masks , Nylons , Polyurethanes , Sodium Chloride , Betaine , Water Pollutants, Chemical/analysis , Polyethylene/chemistry , Water
5.
ACS Appl Mater Interfaces ; 14(37): 42483-42493, 2022 Sep 21.
Article in English | MEDLINE | ID: covidwho-2016531

ABSTRACT

Microbial adhesion and contamination on shared surfaces can lead to life-threatening infections with serious impacts on public health, economy, and clinical practices. The traditional use of chemical disinfectants for sanitization of surfaces, however, comes with its share of health risks, such as hazardous effects on the eyes, skin, and respiratory tract, carcinogenicity, as well as environmental toxicity. To address this, we have developed a nonleaching quaternary small molecule (QSM)-based sprayable coating which can be fabricated on a wide range of surfaces such as nylon, polyethylene, surgical mask, paper, acrylate, and rubber in a one-step, photocuring technique. This contact-active coating killed pathogenic bacteria and fungi including drug-resistant strains of Staphylococcus aureus and Candida albicans within 15-30 min of contact. QSM coatings withstood multiple washes, highlighting their durability. Interestingly, the coated surfaces exhibited rapid killing of pathogens, leading to the prevention of their transmission upon contact. The coating showed membrane disruption of bacterial cells in fluorescence and electron microscopic investigations. Along with bacteria and fungi, QSM-coated surfaces also showed the complete killing of high loads of influenza (H1N1) and SARS-CoV-2 viruses within 30 min of exposure. To our knowledge, this is the first report of a coating for multipurpose materials applied in high-touch public places, hospital equipment, and clinical consumables, rapidly killing drug-resistant bacteria, fungi, influenza virus, and SARS-CoV-2.


Subject(s)
Anti-Infective Agents , COVID-19 , Disinfectants , Influenza A Virus, H1N1 Subtype , Influenza, Human , Acrylates/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Infective Agents/pharmacology , Bacteria , COVID-19/prevention & control , Disinfectants/pharmacology , Fungi , Humans , Nylons/pharmacology , Polyethylenes/pharmacology , Rubber , SARS-CoV-2
6.
Sci Total Environ ; 833: 155139, 2022 Aug 10.
Article in English | MEDLINE | ID: covidwho-1778446

ABSTRACT

Recent studies have shown that passive sampling is a promising tool for SARS-CoV-2 detection for wastewater-based epidemiology (WBE) application. We have previously developed passive sampling of viruses using polymer membranes in seawater. Even though SARS-CoV-2 was not detected yet in seawater, passive sampling could be optimized for future application in coastal areas close to wastewater treatment plant (WWTP). The aim of this study was to optimize passive sampling of SARS-CoV-2 in sewage and seawater by selecting a suitable membrane, to determine whether the quantities of virus increase over time, and then to determine if passive sampling and traditional sampling are correlated when conducted in a wastewater treatment plant. Nylon and Zetapor allowed the detection of heat inactivated SARS-CoV-2 and of the Porcine Epidemic Diarrhea Virus (PEDV), a coronavirus surrogate, in wastewater and seawater spiked with these 2 viruses, showing an increase in detection between 4 h and 24 h of immersion and significantly higher recoveries of both viruses with nylon in seawater (15%) compared to wastewater (4%). On wastewater samples, both membranes detected the virus, the recovery rate was of about 3% for freshly collected samples, and no significant difference was found between SARS-CoV-2 genome concentration on Zetapor and that in water. In sewage spiked seawater, similar concentrations of genome were found on both membranes, with a mean recovery rate of 16% and 11% respectively for nylon and Zetapor. A 3-weeks monitoring with passive sampler allowed the detection of viruses in the influent of a WWTP with a frequency of 100% and 76% for SARS-CoV-2 and norovirus GII respectively. Passive and traditional sampling gave the same evolution of the SARS-CoV-2 concentration over time. All these results confirmed the interest of passive sampling for virus detection and its potential application for monitoring in the wastewater system for targeted public health actions.


Subject(s)
COVID-19 , Viruses , Animals , Nylons , SARS-CoV-2 , Seawater , Sewage , Swine , Wastewater
7.
Sci Rep ; 11(1): 24318, 2021 12 21.
Article in English | MEDLINE | ID: covidwho-1585786

ABSTRACT

The COVID-19 pandemic presents a unique challenge to the healthcare community due to the high infectivity rate and need for effective personal protective equipment. Zinc oxide nanoparticles have shown promising antimicrobial properties and are recognized as a safe additive in many food and cosmetic products. This work presents a novel nanocomposite synthesis approach, which allows zinc oxide nanoparticles to be grown within textile and face mask materials, including melt-blown polypropylene and nylon-cotton. The resulting nanocomposite achieves greater than 3 log10 reduction (≥ 99.9%) in coronavirus titer within a contact time of 10 min, by disintegrating the viral envelope. The new nanocomposite textile retains activity even after 100 laundry cycles and has been dermatologist tested as non-irritant and hypoallergenic. Various face mask designs were tested to improve filtration efficiency and breathability while offering antiviral protection, with Claros' design reporting higher filtration efficiency than surgical masks (> 50%) for particles ranged 200 nm to 5 µm in size.


Subject(s)
Masks/virology , Nanocomposites/toxicity , SARS-CoV-2/drug effects , Virus Inactivation/drug effects , COVID-19/prevention & control , COVID-19/virology , Filtration/methods , Humans , Metal Nanoparticles/chemistry , Nanocomposites/chemistry , Nylons/chemistry , Polypropylenes/chemistry , SARS-CoV-2/isolation & purification , Textiles/analysis , Zinc Oxide/chemistry
8.
ACS Appl Mater Interfaces ; 13(26): 30317-30325, 2021 Jul 07.
Article in English | MEDLINE | ID: covidwho-1387130

ABSTRACT

Influenza A viruses (IAV) and SARS-CoV-2 can spread via liquid droplets and aerosols. Face masks and other personal protective equipment (PPE) can act as barriers that prevent the spread of these viruses. However, IAV and SARS-CoV-2 are stable for hours on various materials, which makes frequent and correct disposal of these PPE important. Metal ions embedded into PPE may inactivate respiratory viruses, but confounding factors such as adsorption of viruses make measuring and optimizing the inactivation characteristics difficult. Here, we used polyamide 6.6 (PA66) fibers containing embedded zinc ions and systematically investigated if these fibers can adsorb and inactivate SARS-CoV-2 and IAV H1N1 when woven into a fabric. We found that our PA66-based fabric decreased the IAV H1N1 and SARS-CoV-2 titer by approximately 100-fold. Moreover, we found that the zinc content and the virus inactivating property of the fabric remained stable over 50 standardized washes. Overall, these results provide insights into the development of reusable PPE that offer protection against RNA virus spread.


Subject(s)
Influenza A virus/physiology , Nylons/pharmacology , SARS-CoV-2/physiology , Textiles , Virus Inactivation/drug effects , Zinc/pharmacology , Adsorption , Animals , Chlorocebus aethiops , Cotton Fiber , Dogs , HEK293 Cells , Humans , Influenza A virus/drug effects , Ions , Madin Darby Canine Kidney Cells , Polypropylenes/pharmacology , SARS-CoV-2/drug effects , Vero Cells , Viral Load , Zinc Oxide/pharmacology
9.
ACS Appl Bio Mater ; 4(7): 5485-5493, 2021 07 19.
Article in English | MEDLINE | ID: covidwho-1327183

ABSTRACT

Attachment of microbial bodies including the corona virus on the surface of personal protective equipment (PPE) is found to be potential threat of spreading infection. Here, we report the development of a triboelectroceutical fabric (TECF) consisting of commonly available materials, namely, nylon and silicone rubber (SR), for the fabrication of protective gloves on the nitrile platform as model wearable PPE. A small triboelectric device (2 cm × 2 cm) consisting of SR and nylon on nitrile can generate more than 20 V transient or 41 µW output power, which is capable of charging a capacitor up to 65 V in only ∼50 s. The importance of the present work relies on the TECF-led antimicrobial activity through the generation of an electric current in saline water. The fabrication of TECF-based functional prototype gloves can generate hypochlorite ions through the formation of electrolyzed water upon rubbing them with saline water. Further, computational modelling has been employed to reveal the optimum structure and mechanistic pathway of antimicrobial hypochlorite generation. Detailed antimicrobial assays have been performed to establish effectiveness of such TECF-based gloves to reduce the risk from life-threatening pathogen spreading. The present work provides the rationale to consider the studied TECF, or other materials with comparable properties, as a material of choice for the development of self-sanitizing PPE in the fight against microbial infections including COVID-19.


Subject(s)
Anti-Infective Agents/chemistry , Electricity , Personal Protective Equipment , Anti-Infective Agents/metabolism , Anti-Infective Agents/pharmacology , Bacterial Proteins/chemistry , Bacterial Proteins/metabolism , Biomimetic Materials/chemistry , Biomimetic Materials/pharmacology , COVID-19/pathology , COVID-19/prevention & control , COVID-19/virology , Humans , Nylons/chemistry , Personal Protective Equipment/microbiology , Personal Protective Equipment/virology , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/metabolism , Recycling , SARS-CoV-2/drug effects , SARS-CoV-2/isolation & purification , SARS-CoV-2/metabolism , Silicone Elastomers/chemistry , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/metabolism
10.
Am J Otolaryngol ; 42(2): 102872, 2021.
Article in English | MEDLINE | ID: covidwho-1002273

ABSTRACT

AIM: This study was aimed to compare the virological, suspect reported outcomes and provider preferences during COVID-19 swab taking procedure used for sampling. METHODS: The COVID-19 suspects are subjected to nasopharyngeal (NP) and oropharyngeal (OP) swabs for testing. Two types of swabs (Nylon and Dacron) are used for sample collection. Prospectively each suspect's response is collected and assessed for self-reported comfort level. The provider's experience with each suspect and virological outcomes recorded separately. The sample adequacy was compared based on swab types and demographic characteristics. RESULTS: A total of 1008 COVID-19 suspects were considered for comparison of various outcomes. Dacron and flocked Nylon swab sticks are used for taking 530 and 478 samples, respectively. Suspects who underwent the procedure using Nylon swabs were six times more likely to have pain/discomfort compared to when Dacron swab was used (Adj RR (95% CI: 6.76 (3.53 to 13, p=0.0001))). The providers perceived six times more resistance with the Nylon swabs compared to Dacron Swabs (Adj RR (95% CI: 5.96 (3.88 to 9.14, p=0.0001))). The pediatric population had a higher rate of blood staining in Dacron swab [Dacron 66 (80.5%); Nylon 51 (54.8%) p=0.0001]. The sample adequacy rate and laboratory positivity rate were not significantly different from each other. CONCLUSIONS: Given the comparable virological outcomes, the difference in suspect and providers comfort should drive swab selection based on characteristics of the suspects. The bulbous Nylon swab caused more pain/discomfort in adults compared to Dacron.


Subject(s)
Attitude of Health Personnel , COVID-19 Testing , Nasopharynx/virology , Oropharynx/virology , Patient Comfort , Specimen Handling/instrumentation , Adolescent , Adult , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Middle Aged , Nylons , Polyethylene Terephthalates , Prospective Studies , Young Adult
11.
JAMA Intern Med ; 181(4): 463-469, 2021 04 01.
Article in English | MEDLINE | ID: covidwho-966088

ABSTRACT

Importance: During the coronavirus disease 2019 (COVID-19) pandemic, the general public has been advised to wear masks or improvised face coverings to limit transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, there has been considerable confusion and disagreement regarding the degree to which masks protect the wearer from airborne particles. Objectives: To evaluate the fitted filtration efficiency (FFE) of various consumer-grade and improvised face masks, as well as several popular modifications of medical procedure masks that are intended to improve mask fit or comfort. Design, Setting, and Participants: For this study conducted in a research laboratory between June and August 2020, 7 consumer-grade masks and 5 medical procedure mask modifications were fitted on an adult male volunteer, and FFE measurements were collected during a series of repeated movements of the torso, head, and facial muscles as outlined by the US Occupational Safety and Health Administration Quantitative Fit Testing Protocol. The consumer-grade masks tested included (1) a 2-layer nylon mask with ear loops that was tested with an optional aluminum nose bridge and filter insert in place, (2) a cotton bandana folded diagonally once (ie, "bandit" style) or in a (3) multilayer rectangle according to the instructions presented by the US Surgeon General, (4) a single-layer polyester/nylon mask with ties, (5) a polypropylene mask with fixed ear loops, (6) a single-layer polyester gaiter/neck cover balaclava bandana, and (7) a 3-layer cotton mask with ear loops. Medical procedure mask modifications included (1) tying the mask's ear loops and tucking in the side pleats, (2) fastening ear loops behind the head with 3-dimensional-printed ear guards, (3) fastening ear loops behind the head with a claw-type hair clip, (4) enhancing the mask/face seal with rubber bands over the mask, and (5) enhancing the mask/face seal with a band of nylon hosiery over the fitted mask. Main Outcomes and Measures: The primary study outcome was the measured FFE of common consumer-grade and improvised face masks, as well as several popular modifications of medical procedure masks. Results: The mean (SD) FFE of consumer grade masks tested on 1 adult male with no beard ranged from 79.0% (4.3%) to 26.5% (10.5%), with the 2-layer nylon mask having the highest FFE. Unmodified medical procedure masks with ear loops had a mean (SD) FFE of 38.5% (11.2%). All modifications evaluated in this study increased procedure mask FFE (range [SD], 60.3% [11.1%] to 80.2% [3.1%]), with a nylon hosiery sleeve placed over the procedure mask producing the greatest improvement. Conclusions and Relevance: While modifications to improve medical procedure mask fit can enhance the filtering capability and reduce inhalation of airborne particles, this study demonstrates that the FFEs of consumer-grade masks available to the public are, in many cases, nearly equivalent to or better than their non-N95 respirator medical mask counterparts.


Subject(s)
COVID-19/prevention & control , COVID-19/transmission , Masks , Adult , Cotton Fiber , Equipment Design , Filtration/instrumentation , Humans , Male , Nylons , Polyesters , Polypropylenes , Protective Clothing
12.
BMJ Open ; 10(9): e039424, 2020 09 22.
Article in English | MEDLINE | ID: covidwho-788150

ABSTRACT

OBJECTIVE: We examined the ability of fabrics which might be used to create home-made face masks to filter out ultrafine (0.02-0.1 µm) particles at the velocity of adult human coughing. METHODS: Twenty commonly available fabrics and materials were evaluated for their ability to reduce air concentrations of ultrafine particles at coughing face velocities. Further assessment was made on the filtration ability of selected fabrics while damp and of fabric combinations which might be used to construct home-made masks. RESULTS: Single fabric layers blocked a range of ultrafine particles. When fabrics were layered, a higher percentage of ultrafine particles were filtered. The average filtration efficiency of single layer fabrics and of layered combination was found to be 35% and 45%, respectively. Non-woven fusible interfacing, when combined with other fabrics, could add up to 11% additional filtration efficiency. However, fabric and fabric combinations were more difficult to breathe through than N95 masks. CONCLUSIONS: The current coronavirus pandemic has left many communities without access to N95 face masks. Our findings suggest that face masks made from layered common fabric can help filter ultrafine particles and provide some protection for the wearer when commercial face masks are unavailable.


Subject(s)
Coronavirus Infections/transmission , Cough , Masks/supply & distribution , Materials Testing , Particulate Matter , Pneumonia, Viral/transmission , Textiles , Air Filters , Betacoronavirus , COVID-19 , Cellulose , Coronavirus Infections/prevention & control , Cotton Fiber , Humans , Nylons , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Polyesters , Polyurethanes , Respiratory Protective Devices/supply & distribution , SARS-CoV-2 , Wool Fiber
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