The impact of nanotechnology in the current universal COVID-19 crisis. Let's not forget nanosafety!

Protective face mask: an effective weapon against SARS-CoV-2 with controlled environmental pollution

Masks are face coverings that give protection from infectious agents, airborne pathogens, bacteria, viruses, surgical fog, dust, and other chemical hazards by acting as a barrier between the wearer and the environment. In the COVID-19 pandemic, this major personal protective equipment's became essential part of our daily life. The aim of this review is to analyze and discuss the different types of masks with their pros and cons, manufacturing procedures, evaluation criteria, and application with some of the sterilization process for reuse and smart mask. The review used a thorough examination of the literature to analyze the preventive effects of surgical, N95, smart mask, and potential environmental damage from those masks. Several studies and evidence were also examined to understand the efficiency of different mask on different environment. N95 respirators are capable of filtering out non-oil-based 95% air-born particles, and surgical masks act as a protective barrier between the wearer and the environment. The application of spoon bond and melt blown techniques in the fabrication process of those masks improves their protective nature and makes them lightweight and comfortable. But the high demand and low supply forced users to reuse and extend their use after sterilizations, even though those masks are recommended to be used once. Universal masking in the SARS-COV-2 pandemic increased the chance of environmental pollution, so the application of smart masks became essential because of their high protection power and self-sterilizing and reusing capabilities.

Chemical-analytical characterization and leaching of heavy metals associated with nanoparticles and microplastics from commercial face masks and the abundance of personal protective equipment (PPE) waste in three metropolitan cities of South America

In this study, we surveyed the presence of personal protective equipment (PPE) waste on the streets of Bogotá-Colombia, Lima-Perú, and Mar del Plata-Argentina. Furthermore, this work is also focused on the release capacity of Ag, Cu, and Zn metals associated with nanoparticles, and microplastics (MPs) from textile face masks (TFMs) and disposable face masks. According to our results, an association between low-income areas and PPE waste was found, which may be related to the periodicity of waste collection and economic activity. Polymers, like polypropylene, cotton-polyester, and additives, such as CaCO₃, MgO, and Ag/Cu as nanoparticles, were identified. TFMs released high levels of Cu (35,900-60,200 μg·L^-1), Zn (2340-2380 μg·L^-1), and MPs (4528-10,640 particles/piece). Metals associated with nanoparticles leached by face masks did not present any antimicrobial activity against P. aeruginosa. Our study suggests that TFMs may leach large amounts of polluting nano/micromaterials in aquatic environments with potential toxicological effects on organisms.

Biodegradable Silver Nanoparticles Gel and Its Impact on Tomato Seed Germination Rate in In Vitro Cultures

Nanotechnology plays an important role in many fields of science and the economy. A special example of nanostructures is silver nanoparticles (AgNPs) created following the principles of green chemistry, i.e., without the use of toxic reducing compounds. The common tomato (Solanum lycopersicum) is a popular vegetable whose germination and growth process are studied by using, e.g., in vitro cultures. The aim of the experiment was to evaluate the inhibitory effect of the biodegradable gels containing silver nanoparticles on the development of microbial infection and to evaluate their influence on the germination degree of Tomato (Solanum lycopersicum) seeds in in vitro plant cultures. Based on macroscopic and microscopic observations, all experimental samples showed the presence of Gram-positive bacilli as well as mould fungi of the genus Rhizopus, Alternaria and Aspergillus. The study showed that the biocomponents containing silver nanoparticles obtained by using xylose as a reducing agent limit the development of microbial infection and stimulate the germination rate of tomato seeds. They could find their application as biodegradable raw materials in the production of modern disinfecting preparations for research in in vitro cultures. This study allowed to identify new research directions, especially to evaluate the metabolic regulation of seedlings treated with biodegradable silver nanoparticles.

Titanium dioxide particles frequently present in face masks intended for general use require regulatory control

Although titanium dioxide (TiO₂) is a suspected human carcinogen when inhaled, fiber-grade TiO₂ (nano)particles were demonstrated in synthetic textile fibers of face masks intended for the general public. STEM-EDX analysis on sections of a variety of single use and reusable face masks visualized agglomerated near-spherical TiO₂ particles in non-woven fabrics, polyester, polyamide and bi-component fibers. Median sizes of constituent particles ranged from 89 to 184 nm, implying an important fraction of nano-sized particles (< 100 nm). The total TiO₂ mass determined by ICP-OES ranged from 791 to 152,345 µg per mask. The estimated TiO₂ mass at the fiber surface ranged from 17 to 4394 µg, and systematically exceeded the acceptable exposure level to TiO₂ by inhalation (3.6 µg), determined based on a scenario where face masks are worn intensively. No assumptions were made about the likelihood of the release of TiO₂ particles itself, since direct measurement of release and inhalation uptake when face masks are worn could not be assessed. The importance of wearing face masks against COVID-19 is unquestionable. Even so, these results urge for in depth research of (nano)technology applications in textiles to avoid possible future consequences caused by a poorly regulated use and to implement regulatory standards phasing out or limiting the amount of TiO₂ particles, following the safe-by-design principle.

Recent Advancements in the Nanomaterial Application in Concrete and Its Ecological Impact

At present, nanotechnology is a significant research area in different countries, owing to its immense ability along with its economic impact. Nanotechnology is the scientific study, development, manufacturing, and processing of structures and materials on a nanoscale level. It has tremendous application in different industries such as construction. This study discusses the various progressive uses of nanomaterials in concrete, as well as their related health risks and environmental impacts. Nanomaterials such as nanosilica, nano-TiO₂, carbon nanotubes (CNTs), ferric oxides, polycarboxylates, and nanocellulose have the capability to increase the durability of buildings by improving their mechanical and thermal properties. This could cause an indirect reduction in energy usage and total expenses in the concrete industry. However, due to the uncertainties and irregularities in size, shape, and chemical compositions, some nanosized materials might have harmful effects on the environment and human health. Acknowledgement of the possible beneficial impacts and inadvertent dangers of these nanosized materials to the environment will be extremely important when pursuing progress in the upcoming years. This research paper is expected to bring proper attention to the probable effects of construction waste, together with the importance of proper regulations, on the final disposal of the construction waste.

Photocatalytic Treatments for Personal Protective Equipment: Experimental Microbiological Investigations and Perspectives for the Enhancement of Antimicrobial Activity by Micrometric TiO2

The COVID-19 pandemic has led to countries enforcing the use of facial masks to prevent contagion. However, acquisition, reuse, and disposal of personal protective equipment (PPE) has generated problems, in regard to the safety of individuals and environmental sustainability. Effective strategies to reprocess and disinfect PPE are needed to improve the efficacy and durability of this equipment and to reduce waste load. Thus, the addition of photocatalytic materials to these materials, combined with light exposure at specific wavelengths, may represent promising solutions. To this aim, we prepared a series of masks by depositing micrometer-sized TiO2 on the external surfaces; the masks were then contaminated with droplets of bacteria suspensions and the coatings were activated by light radiation at different wavelengths. A significant reduction in the microbial load (over 90%, p < 0.01) was observed using both Gram negative (E. coli) and Gram positive (S. aureus) bacteria within 15 min of irradiation, with UV or visible light, including sunlight or artificial sources. Our results support the need for further investigations on self-disinfecting masks and other disposable PPE, which could positively impact (i) the safety of operators/workers, and (ii) environmental sustainability in different occupational or recreational settings.

Use of nanotechnology in combating coronavirus

Recent COVID-19 pandemic situation caused due to the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) affected global health as well as economics. There is global attention on prevention, diagnosis as well as treatment of COVID-19 infection which would help in easing the current situation. The use of nanotechnology and nanomedicine has been considered to be promising due to its excellent potential in managing various medical issues such as viruses which is a major threat. Nanoparticles have shown great potential in various biomedical applications and can prove to be of great use in antiviral therapy, especially over other conventional antiviral agents. This review focusses on the pathophysiology of SARS-CoV-2 and the progression of the COVID-19 disease followed by currently available treatments for the same. Use of nanotechnology has been elaborated by exploiting various nanoparticles like metal and metal oxide nanoparticles, carbon-based nanoparticles, quantum dots, polymeric nanoparticles as well as lipid-based nanoparticles along with its mechanism of action against viruses which can prove to be beneficial in COVID-19 therapeutics. However, it needs to be considered that use of these nanotechnology-based approaches in COVID-19 therapeutics only aids the human immunity in fighting the infection. The main function is performed by the immune system in combatting any infection.

Nanotechnology-Based Approaches and Investigational Therapeutics against COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel coronavirus which is currently responsible for the global pandemic since December 2019. This class of coronavirus has affected 217 countries around the world. Most of the countries have taken some non-remedial preventive actions like country lockdown, work from home, travel bans, and the most significant one is social isolation. Pharmacists, doctors, nurses, technologists, and all other healthcare professionals are playing a pivotal role during this pandemic. Unluckily, there is no specific drug that can treat patients who are confirmed with COVID-19, though favipiravir and remdesivir have appeared as favorable antiviral drugs. Some vaccines have already developed, and vaccination has started worldwide. Different nanotechnologies are in the developing stage in many countries for preventing SARS-COV-2 and treating COVID-19 conditions. In this article, we review the COVID-19 pandemic situation as well as the nanotechnology-based approaches and investigational therapeutics against COVID-19.

Face masks and nanotechnology: Keep the blue side up

Coronavirus Disease 2019 (COVID-19) is one of the biggest challenges of the 21st century. While researchers are working on vaccine development and elucidating the mechanism of action and evolution of the harmful SARS-CoV-2, the current most important public health measure, second only to social distancing, is the obligatory wearing of facial protection. The Centers for Disease Control and Prevention recommended in April 2020 that the public wear face coverings in areas with high rates of transmission based on epidemiological evidence on the strong relationship between mask wearing and pandemic control. This protection against SARS-CoV-2 and other airborne pathogens, boost the design and production of innovative solutions by industry stakeholders. Nanoparticles, nanofibers, and other pioneering technologies based on nanomaterials have been introduced in mask production chains to improve performance and confer antiviral properties. During an emergency like COVID-19, these products directly available to the public should be carefully analyzed in terms of efficacy and possible long-term effects on the wearers' skin and lungs as well as on the environment. This opinion paper provides a wealth of information on the role of nanotechnologies in improving the performance of facial masks and on possible future consequences caused by a poorly regulated use of nanotechnology in textiles.

Applications of nanotechnology in virus detection, tracking, and infection mechanisms

Viruses are among the most infectious pathogens, responsible for the highest death toll around the world. Lack of effective clinical drug for most of the viruses emphasizes the rapid and accurate diagnosis at early stages of infection to prevent rapid spread of the pathogens. Nanotechnology is an emerging field with applications in various domains, where nano‐biomedical science has many significant contributions such as effective delivery of drugs/therapeutic molecules to specific organs, imaging, sensitive detection of virus, and their accurate tracking in host cells. The nanomaterials reported for virus detection and tracking mainly include magnetic and gold NPs, ZnO/Pt‐Pd, graphene, and quantum dots (QDs). In addition, the single virus tracking technology (SVT) allowed to track the life cycle stages of an individual virus for better understanding of their dynamics within the living cells. Inorganic as well as non‐metallic fluorescent materials share the advantages of high photochemical stability, a wide range of light absorption curves and polychromatic emission. Hence, are considered as potential fluorescent nano‐probes for SVT. However, there are still some challenges: (i) clinical false positive rate of some detection methods is still high; (ii) in the virus tracking process, less adaptability of QDs owing to larger size, flicker, and possible interference with virus function; and (iii) in vivo tracking of a single virus, in real time needs further refinement. In the future, smaller, non‐toxic, and chemically stable nanomaterials are needed to improve the efficiency and accuracy of detection, and monitoring of virus infections to curb the mortalities.

This article is categorized under:

Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease

Biology‐Inspired Nanomaterials > Protein and Virus‐Based Structures