A novel anti-influenza copper oxide containing respiratory face mask.

BACKGROUND: Protective respiratory face masks protect the nose and mouth of the wearer from vapor drops carrying viruses or other infectious pathogens. However, incorrect use and disposal may actually increase the risk of pathogen transmission, rather than reduce it, especially when masks are used by non-professionals such as the lay public. Copper oxide displays potent antiviral properties. A platform technology has been developed that permanently introduces copper oxide into polymeric materials, conferring them with potent biocidal properties. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrate that impregnation of copper oxide into respiratory protective face masks endows them with potent biocidal properties in addition to their inherent filtration properties. Both control and copper oxide impregnated masks filtered above 99.85% of aerosolized viruses when challenged with 5.66+/-0.51 and 6.17+/-0.37 log(10)TCID(50) of human influenza A virus (H1N1) and avian influenza virus (H9N2), respectively, under simulated breathing conditions (28.3 L/min). Importantly, no infectious human influenza A viral titers were recovered from the copper oxide containing masks within 30 minutes (< or = 0.88 log(10)TCID(50)), while 4.67+/-1.35 log(10)TCID(50) were recovered from the control masks. Similarly, the infectious avian influenza titers recovered from the copper oxide containing masks were < or = 0.97+/-0.01 log(10)TCID(50) and from the control masks 5.03+/-0.54 log(10)TCID(50). The copper oxide containing masks successfully passed Bacterial Filtration Efficacy, Differential Pressure, Latex Particle Challenge, and Resistance to Penetration by Synthetic Blood tests designed to test the filtration properties of face masks in accordance with the European EN 14683:2005 and NIOSH N95 standards. CONCLUSIONS/SIGNIFICANCE: Impregnation of copper oxide into respiratory protective face masks endows them with potent anti-influenza biocidal properties without altering their physical barrier properties. The use of biocidal masks may significantly reduce the risk of hand or environmental contamination, and thereby subsequent infection, due to improper handling and disposal of the masks.

Molecular mechanisms of enhanced wound healing by copper oxide-impregnated dressings.

ABSTRACT Copper plays a key role in angiogenesis and in the synthesis and stabilization of extracellular matrix skin proteins, which are critical processes of skin formation. We hypothesized that introducing copper into wound dressings would enhance wound repair. Application of wound dressings containing copper oxide to wounds inflicted in genetically engineered diabetic mice (C57BL/KsOlaHsd-Lepr(db)) resulted in increased gene and in situ up-regulation of proangiogenic factors (e.g., placental growth factor, hypoxia-inducible factor-1 alpha, and vascular endothelial growth factor), increased blood vessel formation (p<0.05), and enhanced wound closure (p<0.01) as compared with control dressings (without copper) or commercial wound dressings containing silver. This study proves the capacity of copper oxide-containing wound dressings to enhance wound healing and sheds light onto the molecular mechanisms by which copper oxide-impregnated dressings stimulate wound healing.

Copper oxide impregnated wound dressing: biocidal and safety studies.

 Copper plays a key role in angiogenesis and in the expression and stabilization of extracellular skin proteins. Copper also exhibits broad biocidal properties. The authors hypothesized that introducing copper into a wound dressing would not only reduce the risk of wound and dressing contamination, but would also stimulate wound repair. To test this hypothesis, non-stick dressings composed of a highly absorbent internal mesh fabric and an external non-woven fabric were fabricated, and each was impregnated with ~2.65% (weight/weight) copper oxide particles. The application to wounds inflicted in genetically engineered diabetic mice resulted in increased gene and in-situ upregulation of proangiogenic factors, increased blood vessel formation, and enhanced wound closure. The present study reports both the potent broad spectrum antimicrobial and antifungal properties of these wound dressings and the lack of adverse reactions as determined in rabbits and a porcine wound model. The prolonged efficacy of the wound dressing is demonstrated by its capacity to reduce the microbial challenge by more than 99.9% even when spiked 5 consecutive times with a high bacterial titer. The dressing's antimicrobial efficacy is exerted within minutes. The dressing did not cause any skin irritation or sensitization to closed skin. Furthermore, no histological differences were found between open wounds exposed to copper oxide containing wound dressings or control dressings. Therefore, copper containing wound dressings hold significant promise in wound healing and their clinical use should be explored .

Reducing the risk of skin pathologies in diabetics by using copper impregnated socks.

Diabetic individuals frequently suffer from skin pathologies, especially in their feet. Co-existing peripheral vascular disease and neuropathy exacerbate the capacity of these individuals to cope with infections, minor cuts and wounds, often leading to hard to treat and chronic ulcers. Copper has potent anti-fungal and antibacterial properties. Copper is also an essential trace element vital for the normal function of many tissues and indispensable for the generation of new capillaries and skin. Human skin is not sensitive to copper and the risk of adverse reactions due to dermal exposure to copper is extremely low. We hypothesize that part of the increased risk of developing foot skin pathologies in diabetic patients with compromised blood circulation to the foot is due to low local copper levels. We further hypothesize that copper ions released from copper impregnated socks and absorbed through the skin would improve the well-being of the skin of diabetic patients by inducing angiogenesis and expression and stabilization of extracellular skin proteins, in addition to their biocidal effect of reducing the risk of fungal and bacterial infection of the diabetic foot. Thus, the use of copper impregnated socks may be used as a preventive modality. Furthermore, we hypothesize that the copper released from the socks may even be beneficial in the healing of cuts, wounds and even hard to treat skin pathologies.

Deactivation of human immunodeficiency virus type 1 in medium by copper oxide-containing filters.

Human immunodeficiency virus type 1 (HIV-1) can be transmitted through breast-feeding and through contaminated blood donations. Copper has potent biocidal properties and has been found to inactivate HIV-1 infectivity. The objective of this study was to determine the capacity of copper-based filters to inactivate HIV-1 in culture media. Medium spiked with high titers of HIV-1 was exposed to copper oxide powder or copper oxide-impregnated fibers or passed through copper-based filters, and the infectious viral titers before and after treatment were determined. Cell-free and cell-associated HIV-1 infectivity was inhibited when exposed to copper oxide in a dose-dependent manner, without cytotoxicity at the active antiviral copper concentrations. Similar dose-dependent inhibition occurred when HIV-1 was exposed to copper-impregnated fibers. Filtration of HIV-1 through filters containing the copper powder or copper-impregnated fibers resulted in viral deactivation of all 12 wild-type or drug-resistant laboratory or clinical, macrophage-tropic and T-cell-tropic, clade A, B, or C, HIV-1 isolates tested. Viral inactivation was not strain specific. Thus, a novel means to inactivate HIV-1 in medium has been developed. This inexpensive methodology may significantly reduce HIV-1 transmission from "mother to child" and/or through blood donations if proven to be effective in breast milk or plasma and safe for use. The successful application of this technology may impact HIV-1 transmission, especially in developing countries where HIV-1 is rampant.

Could chronic wounds not heal due to too low local copper levels?

Copper is an essential trace element involved in numerous human physiological and metabolic processes. It plays a key role in many of the processes that together comprise wound healing, including induction of endothelial growth factor, angiogenesis and expression and stabilization of extracellular skin proteins. We hypothesize that in individuals with diabetic ulcers, decubitus, peripheral vascular, or other wounds which might have compromised circulation to the wound site, that part of the incapacity of the wounds to heal is due to low local copper levels. Contamination of wounds is also an important factor causing impaired wound healing. Importantly, copper has potent broad biocidal properties. In contrast, the risk of adverse skin reactions due to exposure to copper is extremely low. We thus hypothesize that introducing copper into wound dressings would not only reduce the risk of wound and dressing contamination, as silver does but, more importantly, would stimulate faster wound repair directly. This would be done by the release of copper from the wound dressings directly into the wound site inducing angiogenesis and skin regeneration.

Biocidal textiles can help fight nosocomial infections.

The rates of nosocomial infections, especially by those caused by antibiotic resistant bacteria, are increasing alarmingly over the globe. Although more rigorous infection control measures are being implemented, it is clear that the current modalities to reduce nosocomial infections are not sufficient. Textiles are an excellent substrate for bacterial growth under appropriate moisture and temperature conditions. Patients shed bacteria and contaminate their pyjamas and sheets. The temperature and humidity between the patients and the bed are appropriate conditions allowing for effective bacterial proliferation. Several studies have found that personnel in contact with contaminated textiles were the source of transmission of the micro-organisms to susceptible patients. Furthermore, it has been reported that bed making in hospitals releases large quantities of micro-organisms into the air, which contaminate the immediate and non-immediate surroundings. Contaminated textiles in hospitals can thus be an important source of microbes contributing to endogenous, indirect-contact, and aerosol transmission of nosocomial related pathogens. We hypothesize that the use of antimicrobial textiles, especially in those textiles that are in close contact with the patients, may significantly reduce bioburden in clinical settings and consequently reduce the risk of nosocomial infections. These textiles should possess broad spectrum biocidal properties. They should be safe for use and highly effective against antibiotic resistant micro-organisms, including those that are commonly involved in hospital-acquired infections, and they should not permit the development of resistant micro-organisms to the active compound.

Neutralizing viruses in suspensions by copper oxide-based filters.

We report the capacity of copper oxide-containing filters to reduce infectious titers of a panel of viruses spiked into culture media. Enveloped, nonenveloped, RNA, and DNA viruses were affected, suggesting the possibility of using copper oxide-containing devices to deactivate a wide spectrum of infectious viruses found in filterable suspensions.

Copper as a biocidal tool.

Copper ions, either alone or in copper complexes, have been used to disinfect liquids, solids and human tissue for centuries. Today copper is used as a water purifier, algaecide, fungicide, nematocide, molluscicide as well as an anti-bacterial and anti-fouling agent. Copper also displays potent anti-viral activity. This article reviews (i) the biocidal properties of copper; (ii) the possible mechanisms by which copper is toxic to microorganisms; and (iii) the systems by which many microorganisms resist high concentrations of heavy metals, with an emphasis on copper.

Putting copper into action: copper-impregnated products with potent biocidal activities.

Copper ions, either alone or in copper complexes, have been used for centuries to disinfect liquids, solids, and human tissue. Today copper is used as a water purifier, algaecide, fungicide, nematocide, molluscicide, and antibacterial and antifouling agent. Copper also displays potent antiviral activity. We hypothesized that introducing copper into clothing, bedding, and other articles would provide them with biocidal properties. A durable platform technology has been developed that introduces copper into cotton fibers, latex, and other polymeric materials. This study demonstrates the broad-spectrum antimicrobial (antibacterial, antiviral, antifungal) and antimite activities of copper-impregnated fibers and polyester products. This technology enabled the production of antiviral gloves and filters (which deactivate HIV-1 and other viruses), antibacterial self-sterilizing fabrics (which kill antibiotic-resistant bacteria, including methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococci), antifungal socks (which alleviate symptoms of athlete's foot), and anti-dust mite mattress covers (which reduce mite-related allergies). These products did not have skin-sensitizing properties, as determined by guine pig maximization and rabbit skin irritation tests. Our study demonstrates the potential use of copper in new applications. These applications address medical issues of the greatest importance, such as viral transmissions; nosocomial, or healthcare-associated, infections; and the spread of antibiotic-resistant bacteria.