Silver nanoparticles fabricated in Hepes buffer exhibit cytoprotective activities toward HIV-1 infected cells

Emerging Nanotechnology for the Treatment of Alzheimer's Disease

Nanotechnology is a great choice for medical research, and the green synthesis approach is a novel and better way to synthesize nanoparticles. Biological sources are cost-effective, environmentally friendly, and allow large-scale production of nanoparticles. Naturally obtained 3 β-hydroxy-urs- 12-en-28-oic acids reported for neuroprotective and dendritic structure are reported as solubility enhancers. Plants are free from toxic substances and act as natural capping agents. In this review, the pharmacological properties of ursolic acid (UA) and the structural properties of the dendritic structure are discussed. UA acid appears to have negligible toxicity and immunogenicity, as well as favorable biodistribution, according to the current study, and the dendritic structure improves drug solubility, prevents drug degradation, increases circulation time, and potentially targets by using different pathways with different routes of administration. Nanotechnology is a field in which materials are synthesized at the nanoscale. Nanotechnology could be the next frontier of humankind's technological advancement. Richard Feynman first used the term 'Nanotechnology' in his lecture, "There is Plenty of Room at the Bottom", on 29th December, 1959, and since then, interest has increased in the research on nanoparticles. Nanotechnology is capable of helping humanity by solving major challenges, particularly in neurological disorders like Alzheimer's disease (AD), the most prevalent type, which may account for 60-70% of cases. Other significant forms of dementia include vascular dementia, dementia with Lewy bodies (abnormal protein aggregates that form inside nerve cells), and a number of illnesses that exacerbate frontotemporal dementia. Dementia is an acquired loss of cognition in several cognitive domains that are severe enough to interfere with social or professional functioning. However, dementia frequently co-occurs with other neuropathologies, typically AD with cerebrovascular dysfunction. Clinical presentations show that neurodegenerative diseases are often incurable because patients permanently lose some neurons. A growing body of research suggests that they also advance our knowledge of the processes that are probably crucial for maintaining the health and functionality of the brain. Serious neurological impairment and neuronal death are the main features of neurodegenerative illnesses, which are also extremely crippling ailments. The most prevalent neurodegenerative disorders cause cognitive impairment and dementia, and as average life expectancy rises globally, their effects become more noticeable.

Biological mechanism of ZnO nanomaterials

Modern nanotechnology has made zinc oxide nanomaterials (ZnO NMts) multifunctional, stable, and low cost, enabling them to be widely used in commercial and biomedical fields. With its wide application, the risk of human direct contact and their release into the environment also increases. This review aims to summarize the toxicity studies of ZnO NMts in vivo, including neurotoxicity, inhalation toxicity, and reproductive toxicity. The antibacterial and antiviral mechanisms of ZnO NMts in vitro and the toxicity to eukaryotic cells were summarized. The summary found that it was mainly related to reactive oxygen species (ROS) produced by oxidative stress. It also discusses the potential harm to body and the favorable prospects of the widespread use of antibacterial and antiviral in the future medical field. The review also emphasizes that the dosage and use method of ZnO NMts will be the focus of future biomedical research.

Nanotechnology development in surgical applications: recent trends and developments

This paper gives a detailed analysis of nanotechnology's rising involvement in numerous surgical fields. We investigate the use of nanotechnology in orthopedic surgery, neurosurgery, plastic surgery, surgical oncology, heart surgery, vascular surgery, ophthalmic surgery, thoracic surgery, and minimally invasive surgery. The paper details how nanotechnology helps with arthroplasty, chondrogenesis, tissue regeneration, wound healing, and more. It also discusses the employment of nanomaterials in implant surfaces, bone grafting, and breast implants, among other things. The article also explores various nanotechnology uses, including stem cell-incorporated nano scaffolds, nano-surgery, hemostasis, nerve healing, nanorobots, and diagnostic applications. The ethical and safety implications of using nanotechnology in surgery are also addressed. The future possibilities of nanotechnology are investigated, pointing to a possible route for improved patient outcomes. The essay finishes with a comment on nanotechnology's transformational influence in surgical applications and its promise for future breakthroughs.

Valence-Engineered Oxidase-Mimicking Nanozyme with Specificity for Aromatic Amine Oxidation and Identification

Oxidase-mimicking nanozymes with specificity for catalyzing oxidation of aromatic amines are of great significance for recognition of aromatic amines but rarely reported. Herein, Cu-A nanozyme (synthesized with Cu²⁺ as a node and adenine as a linker) could specifically catalyze oxidation of o-phenylenediamine (OPD) in Britton-Robinson buffer solution. Such a specific catalytic performance was also corroborated with other aromatic amines, such as p-phenylenediamine (PPD), 1,5-naphthalene diamine (1,5-NDA), 1,8-naphthalene diamine (1,8-NDA), and 2-aminoanthracene (2-AA). Moreover, the presence of salts (1 mM NaNO₂, NaHCO₃, NH₄Cl, KCl, NaCl, NaBr, and NaI) greatly mediated the catalytic activity with the order of NaNO₂ < blank ≈ NaHCO₃ < NH₄Cl ≈ KCl ≈ NaCl < NaBr < NaI, which was due to anions sequentially increasing interfacial Cu⁺ content via anionic redox reaction, while the effect of cations was negligible. With the increased Cu⁺ content, K_m decreased and V_max increased, indicating valence-engineered catalytic activity. Based on high specificity and satisfactory activity, a colorimetric sensor array with NaCl, NaBr, and NaI as sensing channels was constructed to identify five representative aromatic amines (OPD, PPD, 1,5-NDA, 1,8-NDA, and 2-AA) as low as 50 μM, quantitatively analyze single aromatic amine (with OPD and PPD as model analysts), and even identify 20 unknown samples with an accuracy of 100%. In addition, the performance was further validated through accurately recognizing various concentration ratios of binary, ternary, quaternary, and quinary mixtures. Finally, the practical applications were demonstrated by successfully discriminating five aromatic amines in tap, river, sewage, and sea water, providing a simple and feasible assay for large-scale scanning aromatic amine levels in environmental water samples.

Nanomedicine for drug resistant pathogens and COVID-19 using mushroom nanocomposite inspired with bacteriocin – A Review

Multidrug resistant (MDR) pathogens have become a major global health challenge and have severely threatened the health of society. Current conditions have gotten worse as a result of the COVID-19 pandemic, and infection rates in the future will rise. It is necessary to design, respond effectively, and take action to address these challenges by investigating new avenues. In this regard, the fabrication of metal NPs utilized by various methods, including green synthesis using mushroom, is highly versatile, cost-effective, eco-compatible, and superior. In contrast, biofabrication of metal NPs can be employed as a powerful weapon against MDR pathogens and have immense biomedical applications. In addition, the advancement in nanotechnology has made possible to modify the nanomaterials and enhance their activities. Metal NPs with biomolecules composite to prevents their microbial adhesion and kills the microbial pathogens through biofilm formation. Bacteriocin is an excellent antimicrobial peptide that works well as an augmentation substance to boost the antimicrobial effects. As a result, we concentrate on the creation of new, eco-compatible mycosynthesized metal NPs with bacteriocin nanocomposite via electrostatic, covalent, or non-covalent bindings. The synergistic benefits of metal NPs with bacteriocin to combat MDR pathogens and COVID-19, as well as other biomedical applications, are discussed in this review. Moreover, the importance of the adverse outcome pathway (AOP) in risk analysis of manufactured metal nanocomposite nanomaterial and their future possibilities also discussed.

Green Biogenic of Silver Nanoparticles Using Polyphenolic Extract of Olive Leaf Wastes with Focus on Their Anticancer and Antimicrobial Activities

Agro-industrial wastes are rich in polyphenols and other bioactive compounds, and valorizing these wastes is a crucial worldwide concern for saving health and the environment. In this work, olive leaf waste was valorized by silver nitrate to produce silver nanoparticles (OLAgNPs), which exhibited various biological, antioxidant, anticancer activities against three cancer cell lines, and antimicrobial activity against multi-drug resistant (MDR) bacteria and fungi. The obtained OLAgNPs were spherical, with an average size of 28 nm, negatively charged at -21 mV, and surrounded by various active groups more than the parent extract based on FTIR spectra. The total phenolic and total flavonoid contents significantly increased in OLAgNPs by 42 and 50% over the olive leaf waste extract (OLWE); consequently, the antioxidant activity of OLAgNPs increased by 12% over OLWE, recording an SC₅₀ of OLAgNPs of 5 µg/mL compared to 30 µg/mL in the extract. The phenolic compound profile detected by HPLC showed that gallic acid, chlorogenic acid, rutin, naringenin, catechin, and propyl gallate were the main compounds in the HPLC profile of OLAgNPs and OLWE; the content of these compounds was higher in OLAgNPs than OLWE by 16-fold. The higher phenolic compounds in OLAgNPs are attributable to the significant increase in biological activities of OLAgNPs than that of OLWE. OLAgNPs successfully inhibited the proliferation of three cancer cell lines, MCF-7, HeLa, and HT-29, by 79-82% compared to 55-67% in OLWE and 75-79% in doxorubicin (DOX). The preliminary worldwide problem is multi-drug resistant microorganisms (MDR) because of the random use of antibiotics. Therefore, in this study, we may find the solution in OLAgNPs with concentrations of 2.5-20 µg/mL, which significantly inhibited the growth of six MDR bacteria L. monocytogenes, B. cereus, S. aureus, Y. enterocolitica, C. jejuni, and E. coli with inhibition zone diameters of 25-37 mm and six pathogenic fungi in the range of 26-35 mm compared to antibiotics. OLAgNPs in this study may be applied safely in new medicine to mitigate free radicals, cancer, and MDR pathogens.

Antimicrobial finishing of textiles using nanomaterials

Metals, such as copper and silver, can be extremely toxic to bacteria at exceptionally low concentrations. Because of this biocidal activity, metals have been widely used as antimicrobial agents in a multitude of applications related with agriculture, healthcare, and the industry in general. A large number of microorganisms live in the human environment. if the balance of these creatures in nature is disturbed, the health of the individual and society will be threatened due to the production and emission of unpleasant odors and the reduction of health standards. The presence of microorganisms on textiles can cause adverse effects such as discoloration or staining on textiles, decomposition of fibrous materials, reduced strength, and eventually decay of textiles. Most fibers and polymers do not show resistance to the effects of microbes and by providing growth factors for microorganisms such as the right temperature and humidity, nutrients from sweat and fat from skin glands, dead skin cells as well as materials used in the stage of finishing the textiles causes the rapid growth and spread of various microbes. With the advent of nanotechnology, various industries and human daily life underwent changes. In recent years, increasing research on nanoparticles has led to the production of textiles with greater efficiency and added value. These modified textiles prevent the spread of unpleasant odors, the spread, and transmission of diseases. This article reviews the basics and principles of antimicrobial tetiles, as well as a brief overview of antimicrobial materials and nanostructures with antimicrobial properties.

SARS-CoV-2 and its new variants: a comprehensive review on nanotechnological application insights into potential approaches

SARS-CoV-2 (COVID-19) spreads and develops quickly worldwide as a new global crisis which has left deep socio-economic damage and massive human mortality. This virus accounts for the ongoing outbreak and forces an urgent need to improve antiviral therapeutics and targeted diagnosing tools. Researchers have been working to find a new drug to combat the virus since the outbreak started in late 2019, but there are currently no successful drugs to control the SARS-CoV-2, which makes the situation riskier. Very recently, new variant of SARS-CoV-2 is identified in many countries which make the situation very critical. No successful treatment has yet been shown although enormous international commitment to combat this pandemic and the start of different clinical trials. Nanomedicine has outstanding potential to solve several specific health issues, like viruses, which are regarded a significant medical issue. In this review, we presented an up-to-date drug design strategy against SARS-CoV-2, including the development of novel drugs and repurposed product potentials were useful, and successful drugs discovery is a constant requirement. The use of nanomaterials in treatment against SARS-CoV-2 and their use as carriers for the transport of the most frequently used antiviral therapeutics are discussed systematically here. We also addressed the possibilities of practical applications of nanoparticles to give the status of COVID-19 antiviral systems.

Characterization of Ag-Ion Releasing Zeolite Filled 3D Printed Resins

There has been profound growth in the use of 3D printed materials in dentistry in general, including orthodontics. The opportunity to impart antimicrobial properties to 3D printed parts from existing resins requires the capability of forming a stable colloid incorporating antimicrobial fillers. The objective of this research was to characterize a colloid consisting of a 3D printable resin mixed with Ag-ion releasing zeolites and fumed silica to create 3D printed parts with antiviral properties. The final composite was tested for antiviral properties against SARS-CoV-2 and HIV-1. Antiviral activity was measured in terms of the half-life of SARS-CoV-2 and HIV-1 on the composite surface. The inclusion of the zeolite did not interfere with the kinetics measured on the surface of the ATR crystal. While the depth of cure, measured following ISO4049 guidelines, was reduced from 3.8 mm to 1.4 mm in 5 s, this greatly exceeded the resolution required for 3D printing. The colloid was stable for at least 6 months and the rheological behavior was dependent upon the fumed silica loading. The inclusion of zeolites and fumed silica significantly increased the flexural strength of the composite as measured by a 3 point bend test. The composite released approximately 2500 μg/L of silver ion per gram of composite as determined by potentiometry. There was a significant reduction of the average half-life of SARS-CoV-2 (1.9 fold) and HIV-1 (2.7 fold) on the surface of the composite. The inclusion of Ag-ion releasing zeolites into 3D-printable resin can result in stable colloids that generate composites with improved mechanical properties and antiviral properties.

Nano-antivirals: A comprehensive review

Nanoparticles can be used as inhibitory agents against various microorganisms, including bacteria, algae, archaea, fungi, and a huge class of viruses. The mechanism of action includes inhibiting the function of the cell membrane/stopping the synthesis of the cell membrane, disturbing the transduction of energy, producing toxic reactive oxygen species (ROS), and inhibiting or reducing RNA and DNA production. Various nanomaterials, including different metallic, silicon, and carbon-based nanomaterials and nanoarchitectures, have been successfully used against different viruses. Recent research strongly agrees that these nanoarchitecture-based virucidal materials (nano-antivirals) have shown activity in the solid state. Therefore, they are very useful in the development of several products, such as fabric and high-touch surfaces. This review thoroughly and critically identifies recently developed nano-antivirals and their products, nano-antiviral deposition methods on various substrates, and possible mechanisms of action. By considering the commercial viability of nano-antivirals, recommendations are made to develop scalable and sustainable nano-antiviral products with contact-killing properties.

Antiviral efficacy of cerium oxide nanoparticles

Nanomaterials are prospective candidates for the elimination of viruses due to their multimodal mechanisms of action. Here, we tested the antiviral potential of a largely unexplored nanoparticle of cerium dioxide (CeO₂). Two nano-CeO₂ with opposing surface charge, (+) and (-), were assessed for their capability to decrease the plaque forming units (PFU) of four enveloped and two non-enveloped viruses during 1-h exposure. Statistically significant antiviral activity towards enveloped coronavirus SARS-CoV-2 and influenza virus was registered already at 20 mg Ce/l. For other two enveloped viruses, transmissible gastroenteritis virus and bacteriophage φ6, antiviral activity was evidenced at 200 mg Ce/l. As expected, the sensitivity of non-enveloped viruses towards nano-CeO₂ was significantly lower. EMCV picornavirus showed no decrease in PFU until the highest tested concentration, 2000 mg Ce/l and MS2 bacteriophage showed slight non-monotonic response to high concentrations of nano-CeO₂(-). Parallel testing of antiviral activity of Ce³⁺ ions and SiO₂ nanoparticles allows to conclude that nano-CeO₂ activity was neither due to released Ce-ions nor nonspecific effects of nanoparticulates. Moreover, we evidenced higher antiviral efficacy of nano-CeO₂ compared with Ag nanoparticles. This result along with low antibacterial activity and non-existent cytotoxicity of nano-CeO₂ allow us to propose CeO₂ nanoparticles for specific antiviral applications.

Thermoplasmonics Decontamination of Respirators Face Masks Using Silver Nanoparticles: A New Weapon in the Fight Against COVID-19 Pandemic

The current COVID-19 pandemic has resulted in an urgent need for methods to decontaminate respirators masks for reuse while keeping them intact and functional. The severe shortage of professional masks such as N95 and FFP2 has necessitated their reuse over long periods. A very promising method is the pasteurization of these masks by thermoplasmonic heat generated by plasmonics nanoparticles when they are irradiated by light. Under illumination at its plasmonic resonance, a metal nanoparticle features enhanced light absorption, turning it into an ideal nano-source of heat, remotely controllable using light. In this work, we propose a numerical study based on the finite element method (FEM) of the thermoplasmonic properties of silver nanoparticles (AgNPs) decorating polypropylene (PP) fibers which is a basic material for the manufacture of these masks. The surface plasmon resonance (SPR) of these nanostructures was investigated through the computation of the complex effective dielectric permittivity and the absorption cross section in the near UV-visible (NUV-Vis) range. First, the SPR characteristics of AgNPs for different morphologies are determined from the absorption spectra, including the SPR-peak position λ_max and the electric field enhancement. Second, we determine the power absorbed by an individual AgNP of different morphologies. From this, we calculate the internal temperature increase of the particle at the plasmonic resonance. The last step is devoted to the determination of the temperature profile in the surrounding medium in order to better understand and design the plasmon-assisted heating processes at the nanometric scale.

Amine-Functionalized Silver Nanoparticles: A Potential Antiviral-Coating Material with Trap and Kill Efficiency to Combat Viral Dissemination (COVID-19)

The outbreak of COVID-19 has drastically affected the daily lifestyles of people globally where specific Coronavirus-2 transmits primarily by respiratory droplets. Structurally, the SARS-CoV-2 virus is made up of four types of proteins in which S-protein is indispensable among them, as it causes rapid replication in the host body. Therefore, the glycine and alanine composed of HR1 of S-protein is the ideal target for antiviral action. Different forms of surface-active PPEs can efficiently prevent this transmission in this circumstance. However, the virus can survive on the conventional PPEs for a long time. Hence, the nanotechnological approaches based on engineered nanomaterials coating on medical equipments can potentially prevent the dissemination of infections in public. Silver nanoparticles with tuneable physicochemical properties and versatile chemical functionalization provide an excellent platform to combat the disease. The coating of amine-functionalized silver nanoparticle (especially amine linked to aliphatic chain and trialkoxysilane) in its nanostructured form enables cloths trap and kill efficient. PPEs are a primary and reliable preventive measure, although they are not 100% effective against viral infections. So, developing and commercializing surface-active PPEs with trap and kill efficacy is highly needed to cope with current and future viral infections. This review article discusses the COVID-19 morphology, antiviral mechanism of Ag-NPs against SARS-CoV-2 virus, surface factors that influence viral persistence on fomites, the necessity of antiviral PPEs, and the potential application of amine-functionalized silver nanoparticles as a coating material for the development of trap and kill-efficient face masks and PPE kits.

In ovo nano-silver and nutrient supplementation improves immunity and resistance against Newcastle disease virus challenge in broiler chickens

Silver nanoparticles (AgNPs) interact with the microbes and host immune system to protect against diseases. Fertile broiler eggs (n = 900) were allotted to six groups: un-injected control, sham (sterile water), AgNPs (50 μg), AgNPs+Amino acids (Methionine-10 mg + Arginine-25 mg), AgNPs+Vitamins (Vit B1-72μg + Vit B6-140μg), and AgNPs+Trace Elements (Zn-80 μg and Se-0.3 μg) and incubated for 18 days. On 18th embryonic day, 0.6 ml test solution was injected at the broad end of egg using 25 mm needle and transferred to hatcher. Post-hatch, half of the chicks from each group were vaccinated with Newcastle disease (ND) vaccine, and the other half were kept as unvaccinated unit and reared for 42 d with standard management practices. Hatchability, 1st and 42nd d body weight, feed intake, and feed conversion ratio were similar between treatment groups in both vaccinated and unvaccinated units. The relative weight of bursa Fabricius and thymus was similar, but spleen weight was higher (P ≤ 0.05) in AgNPs, AgNPs+Vits, and AgNPs+TEs chicks than control group. Cellular immune response (against mitogen phytohemagglutinin-P) was higher (P ≤ 0.05) in AgNPs+TEs chicks, whereas HA titer against sheep red blood cells antigen, serum IgG, IgM, and HI titer against ND vaccine was apparently higher in AgNPs+Vits group chicks than control. No clinical symptoms were observed in the vaccinated groups except for a few control birds 6 days postchallenge (PC). Three days PC, unvaccinated birds show depression, off feed, greenish diarrhea, and nasal discharge and the control group started dying. The highest cumulative infection (CI) was observed in sham (79.17%) and un-injected control (75%), but lowest in AgNPs+AAs birds (58.33%) on 3rd dpi. The CI reached 100% on 5th dpi in control groups and AgNPs, and 91.67% and 93.75% in AgNPs+TEs and AgNPs+AAs group, respectively. The AgNPs+TEs and AgNPs+AAs group birds lived for more than 90 h compared to 75 h in control groups and also had higher IL-6 and IL-2 gene expressions at 24 h PC. It was concluded that 50 μg/egg AgNPs with vitamins (B1 and B6) and trace elements (Zn and Se) improved performance, but AgNPs with trace elements and amino acids enhanced immune response and resistance against vND virus challenge in broilers.

Preparation and Application of In-Situ Loaded Silver Nanoparticles Antibacterial Fresh-Keeping Composite Paper

The freshness and safety of fruits and vegetables affect our daily life. Paper products are often used in the packaging and transportation of fruits and vegetables, and these can provide other functions besides packaging after certain modifications and additions. In this study, the AgNPs/1-MCP antibacterial fresh-keeping composite paper was prepared by in-situ loaded silver nanoparticles and spraying 1-MCP solution. Moreover, the prepared paper was used to preserve sweet cherries. It was found that the prepared AgNPs/1-MCP antibacterial fresh-keeping composite paper could effectively inhibit E. coli and S. aureus. When the addition of 1-MCP in the paper was 0.05 g, the fresh-keeping effect on cherries was the best. Under this optimal condition, the weight loss ratio of the cherries was reduced by 1.93%, the firmness was increased by 27.7%, and the soluble solid content was increased by 25%. The preservation time was extended from 4 days to 12 days, three times that of the untreated ones. The prepared fresh-keeping material is environmentally friendly, non-toxic and harmless, simple to prepare and convenient to use, and is expected to become one of the important fresh-keeping methods for fruits.

Gestational exposure to silver nanoparticles enhances immune adaptation and protection against streptozotocin-induced diabetic nephropathy in mice offspring

Silver nanoparticles (AgNPs) possess unique antimicrobial properties. As a result, they are being increasingly used in a wide range of applications. Several studies have shown detrimental effects of AgNPs exposure, including inflammation, accumulation, and cellular damage to different organs. However, the effect of AgNPs exposure during gestation, a critical and susceptible period of human development, on pregnant females and its long-term effects on offspring's health has not been studied. Therefore, we conducted a long-term study where we assessed the effect of gestational AgNPs exposure on pregnant mice and followed their offspring until the age of 12 months. Gestational exposure to AgNPs induced systemic inflammation in the pregnant mice at gestational day (GD) 18. Interestingly, developing fetuses exposed to AgNPs, showed anti-inflammatory conditions as indicated by reduced expression of inflammatory genes in fetal organs at GD 18 and reduced serum levels of TNF-α, IFN-γ, IL-17A, IL-6, and MCP-1 in AgNPs exposed pups at postnatal day (PD) 2. Surprisingly, post-weaning, AgNPs exposed offspring showed a heightened immune activation as shown by upregulation of inflammatory cytokines at PD 28, which persisted till late in life. Moreover, we observed metabolic alterations which persisted until adulthood in mice. To understand the impact of long-term immunometabolic changes on the progression of diabetes and kidney diseases under stressed conditions, we exposed offspring to streptozotocin which revealed a protective role of low-dose gestational AgNPs exposure against streptozotocin-induced diabetes and associated nephropathy.

Silver Nanoparticles–Polyethyleneimine-Based Coatings with Antiviral Activity against SARS-CoV-2: A New Method to Functionalize Filtration Media

The use of face masks and air purification systems has been key to curbing the transmission of SARS-CoV-2 aerosols in the context of the current COVID-19 pandemic. However, some masks or air conditioning filtration systems are designed to remove large airborne particles or bacteria from the air, being limited their effectiveness against SARS-CoV-2. Continuous research has been aimed at improving the performance of filter materials through nanotechnology. This article presents a new low-cost method based on electrostatic forces and coordination complex formation to generate antiviral coatings on filter materials using silver nanoparticles and polyethyleneimine. Initially, the AgNPs synthesis procedure was optimized until reaching a particle size of 6.2 ± 2.6 nm, promoting a fast ionic silver release due to its reduced size, obtaining a stable colloid over time and having reduced size polydispersity. The stability of the binding of the AgNPs to the fibers was corroborated using polypropylene, polyester-viscose, and polypropylene-glass spunbond mats as substrates, obtaining very low amounts of detached AgNPs in all cases. Under simulated operational conditions, a material loss less than 1% of nanostructured silver was measured. SEM micrographs demonstrated high silver distribution homogeneity on the polymer fibers. The antiviral coatings were tested against SARS-CoV-2, obtaining inactivation yields greater than 99.9%. We believe our results will be beneficial in the fight against the current COVID-19 pandemic and in controlling other infectious airborne pathogens.

Antiviral potential of nanoparticles for the treatment of Coronavirus infections

BACKGROUND

On 31st December 2019 in Wuhan, China, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), was acknowledged. This virus spread quickly throughout the world causing a global pandemic. The World Health Organization declared COVID-19 a pandemic disease on 11th March 2020. Since then, the whole world has come together and have developed several vaccines against this deadly virus. Similarly, several alternative searches for pandemic disease therapeutics are still ongoing. One of them has been identified as nanotechnology. It has demonstrated significant promise for detecting and inhibiting a variety of viruses, including coronaviruses. Several nanoparticles, including gold nanoparticles, silver nanoparticles, quantum dots, carbon dots, graphene oxide nanoparticles, and zinc oxide nanoparticles, have previously demonstrated remarkable antiviral activity against a diverse array of viruses.

OBJECTIVE

This review aims to provide a basic and comprehensive overview of COVID-19's initial global outbreak and its mechanism of infiltration into human host cells, as well as the detailed mechanism and inhibitory effects of various nanoparticles against this virus. In addition to nanoparticles, this review focuses on the role of several antiviral drugs used against COVID-19 to date.

CONCLUSION

COVID-19 has severely disrupted the social and economic lives of people all over the world. Due to a lack of adequate medical facilities, countries have struggled to maintain control of the situation. Neither a drug nor a vaccine has a 100% efficacy rate. As a result, nanotechnology may be a better therapeutic alternative for this pandemic disease.

Antiviral nanopharmaceuticals: Engineered surface interactions and virus-selective activity

The COVID-19 pandemic has inspired large research investments from the global scientific community in the study of viral properties and antiviral technologies (e.g., self-cleaning surfaces, virucides, antiviral drugs, and vaccines). Emerging viruses are a constant threat due to the substantial variation in viral structures, limiting the potential for expanded broad-spectrum antiviral agent development, and the complexity of targeting multiple and diverse viral species with unique characteristics involving their virulence. Multiple, more infectious variants of SARS-CoV2 (e.g., Delta, Omicron) have already appeared, necessitating research into versatile, robust control strategies in response to the looming threat of future viruses. Nanotechnology and nanomaterials have played a vital role in addressing current viral threats, from mRNA-based vaccines to nanoparticle-based drugs and nanotechnology enhanced disinfection methods. Rapid progress in the field has prompted a review of the current literature primarily focused on nanotechnology-based virucides and antivirals. In this review, a brief description of antiviral drugs is provided first as background with most of the discussion focused on key design considerations for high-efficacy antiviral nanomaterials (e.g., nanopharmaceuticals) as determined from published studies as well as related modes of biological activity. Insights into potential future research directions are also provided with a section devoted specifically to the SARS-CoV2 virus. This article is categorized under: Toxicology and Regulatory Issues in Nanomediciney > Toxicology of Nanomaterials Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease Therapeutic Approaches and Drug Discovery > Nanomedicine for Respiratory Disease.

Inhibitory activity and mechanism of silver nanoparticles against herpes simplex virus type 1

Herpes simplex virus type 1 (HSV-1) is a common pathogen that infects 50-90% of the world's population and causes a variety of diseases, some of which can be life-threatening. Silver nanoparticles (AgNPs) have been shown to have broad-spectrum antiviral activity. In this study, we investigated the activity of AgNPs against HSV-1 and found that AgNPs effectively inhibited plaque formation and HSV-1 progeny production, reduced the genomic load, and interfered with HSV-1 mRNA expression and protein synthesis. Transmission electron microscopy showed that AgNPs interacted with HSV-1 and altered the shape of the viral particles. Furthermore, AgNPs affected the entry of HSV-1 into cells as well as their release and cell-to-cell spread. AgNPs were also found to downregulate the expression of pro-inflammatory cytokines upon HSV-1 infection. Combined treatment with AgNPs and acyclovir (ACV) confirmed that AgNPs significantly enhanced the inhibitory effect of ACV against HSV-1. Our findings may contribute to an understanding of the mechanism of the antiviral effect of AgNPs against HSV-1 and help to provide a theoretical basis for their clinical application.

Impact of Particle Size on Toxicity, Tissue Distribution and Excretion Kinetics of Subchronic Intratracheal Instilled Silver Nanoparticles in Mice

The unique physicochemical properties of silver nanoparticles (AgNPs) make them useful in a wide range of sectors, increasing their propensity for human exposure, as well as the need for thorough toxicological assessment. The biodistribution of silver, hematological parameters and GSH/GSSG levels in the lung and liver were studied in mice that were intratracheally instilled with AgNP (5 and 50 nm) and AgNO₃ once a week for 5 weeks, followed by a recovery period of up to 28 days (dpi). Data was gathered to build a PBPK model after the entry of AgNPs into the lungs. AgNPs could be absorbed into the blood and might cross the physiological barriers and be distributed extensively in mice. Similar to AgNO₃, AgNP5 induced longer-lasting toxicity toward blood cells and increased GSH levels in the lung. The exposure to AgNP50 increased the GSH from 1 dpi onward in the liver and silver was distributed to the organs after exposure, but its concentration decreased over time. In AgNP5 treated mice, silver levels were highest in the spleen, kidney, liver and blood, persisting for at least 28 days, suggesting accumulation. The major route for excretion seemed to be through the urine, despite a high concentration of AgNP5 also being found in feces. The modeled silver concentration was in line with the in vivo data for the heart and liver.

Inhalation exposure to silver nanoparticles induces hepatic inflammation and oxidative stress, associated with altered renin-angiotensin system signaling, in Wistar rats

Silver nanoparticles (AgNPs) have become increasingly popular in the biomedical field over the last few decades due to its proven antibacterial property. Previous scientific studies have reported that one of the major organs responsible for detoxification of AgNPs is the liver. The liver is also the primary organ responsible for secretion of angiotensinogen (AGT), a key signaling molecule involved in the renin-angiotensin system (RAS), which plays an important role in maintaining cardiac output and vascular pressure. The aim of this study was to assess any potential changes in the RAS-associated gene signaling, inflammatory response, and hepatocellular toxicity resulting from AgNP exposure. To do this, 6-week-old, male Wistar rats were exposed to a subacute inhalation exposure of AgNP (200 ppb/days over 4 h/days exposure, for 5 d) and their livers were analyzed for alterations in RAS components, inflammation, and oxidative stress. Real time qPCR analysis showed that AgNP-exposure resulted in a significant increase in hepatic AGT, angiotensin converting enzyme (ACE)-1, and ACE-2 mRNA expression. Expression of inflammatory markers interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α were also upregulated with AgNP-exposure, compared to controls. Furthermore AgNP-exposure mediated a significant increase in hepatic expression of catalase, and superoxide dismutase, and oxidative stress, as assessed via 8-Oxo-2'-deoxyguanosine staining. Increased oxidative stress was associated with increased monocyte/macrophage-2 staining in the liver of AgNP-exposed rats. Such findings indicate that subacute inhalation exposure to AgNPs mediate increased hepatic RAS signaling, associated with inflammation, macrophage infiltration, and oxidative stress.

A Perspective on Reproductive Toxicity of Metallic Nanomaterials

Nanotechnological tools have been greatly exploited in all possible fields. However, advancement of nanotechnology has raised concern about their adverse effects on human and environment. These deleterious effects cannot be ignored and need to be explored due to safety purpose. Several recent studies have demonstrated possible health hazard of nanoparticles on organism. Moreover, studies showed that toxicity of metallic nanomaterial could also lead to reproductive toxicity. Various deleterious effects have demonstrated decreased sperm motility, increased abnormal spermatozoa, altered sperm count, and altered sperm morphology. Morphological and ultrastructural changes also have been reported due to the accumulation of these nanomaterials in reproductive organs. Nonetheless, studies also suggest crossing of metallic nanoparticles through blood testes barrier and generation of oxidative stress which plays major role in reproductive toxicity. In the present study, we have incorporated updated information by gathering all available literature about various metallic nanomaterials and risk related to reproductive system.

AgNPs/nGOx/Apra Nanocomposites for Synergistic Antimicrobial Therapy and Scarless Skin Recovery

The misuse of antimicrobials has caused a remarkable increase of antibiotic-resistant bacteria. Developing novel antimicrobial agents with high activity and low rates of resistance development is in great demand yet...

Emerging importance of nanotechnology-based approaches to control the COVID-19 pandemic; focus on nanomedicine iterance in diagnosis and treatment of COVID-19 patients

The ongoing outbreak of the newly emerged coronavirus disease 2019, which has tremendously concerned global health safety, is the result of infection with severe acute respiratory syndrome of coronavirus 2 with high morbidity and mortality. Because of the coronavirus has no specific treatment, so it is necessary to early detection and produce antiviral agents and efficacious vaccines in order to prevent the contagion of coronavirus. Due to the unique properties of nanomaterials, nanotechnology appears to be a highly relevant discipline in this global emergency, providing expansive chemical functionalization to develop advanced biomedical tools. Fascinatingly, nanomedicine as a hopeful approach for the treatment and diagnosis of diseases, could efficiently help success the fight among coronavirus and host cells. In this review, we will critically discuss how nanomedicine can play an indispensable role in creating useful treatments and diagnostics for coronavirus.

Silver Nanoparticles as Potential Antiviral Agents

Since the early 1990s, nanotechnology has led to new horizons in nanomedicine, which encompasses all spheres of science including chemistry, material science, biology, and biotechnology. Emerging viral infections are creating severe hazards to public health worldwide, recently, COVID-19 has caused mass human casualties with significant economic impacts. Interestingly, silver nanoparticles (AgNPs) exhibited the potential to destroy viruses, bacteria, and fungi using various methods. However, developing safe and effective antiviral drugs is challenging, as viruses use host cells for replication. Designing drugs that do not harm host cells while targeting viruses is complicated. In recent years, the impact of AgNPs on viruses has been evaluated. Here, we discuss the potential role of silver nanoparticles as antiviral agents. In this review, we focus on the properties of AgNPs such as their characterization methods, antiviral activity, mechanisms, applications, and toxicity.

Optimization of hyphenated asymmetric flow field-flow fractionation for the analysis of silver nanoparticles in aqueous solutions

The extensive use of silver nanoparticles (AgNPs) in consumer products, medicine, and industry leads to their release into the environment. Thus, a characterization of the concentration, size, fate, and toxicity of AgNPs under environmental conditions is required. In this study, we present the characterization and optimization of an asymmetric flow field-flow fractionation (AF4) system coupled with UV/Vis spectrophotometer and dynamic light scattering (DLS) detector as a powerful tool for the size separation and multi-parameter characterization of AgNPs in complex matrices. The hyphenated AF4-UV/Vis-DLS system was first characterized using individual injections of the different size fractions. We used electrostatically stabilized AgNPs of 20-, 50-, and 80-nm nominal diameters coated with lipoic acid. We investigated the effect of applied cross-flows, carrier solutions, focus times, and quantity of injected particles on the nature of the AF4 fractograms and on the integrity of the AgNPs. Best size separation of a 1:1 mixture of 20- and 80-nm AgNPs was achieved using cross-flows of 0.5 and 0.7 mL/min with 1 mM NaCl and 0.05% v/v Mucasol as carrier solutions. We also researched the behavior of AgNPs in natural waters using the hyphenated AF4-UV/Vis-DLS system, under determined optimal conditions. Schematic and photograph of the AF4 setup with numbered hardware devices. Dashed lines represent electrical connections; continuous lines represent fluidic connections. For a better overview, not all fluidic connections between pump/6-way valve (2) and the Eclipse AF4 device (3) are shown in the schematic. The fluorescence detector (FL (7)) was not used in the study presented herein.

Silver, copper and copper oxide nanoparticles in the fight against human viruses: progress and perspectives

The rapid development of nanomedicine has created a high demand for silver, copper and copper oxide nanoparticles. Due to their high reactivity and potent antimicrobial activity, silver and copper-based nanomaterials have been playing an important role in the search for new alternatives for the treatment of several issues of concern, such as pathologies caused by bacteria and viruses. Viral diseases are a significant and constant threat to public health. The most recent example is the pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this context, the object of the present review is to highlight recent progress in the biomedical uses of these metal nanoparticles for the treatment and prevention of human viral infections. We discuss the antiviral activity of AgNPs and Cu-based NPs, including their actions against SARS-CoV-2. We also discuss the toxicity, biodistribution and excretion of AgNPs and CuNPs, along with their uses in medical devices or on inert surfaces to avoid viral dissemination by fomites. The challenges and limitations of the biomedical use of these nanoparticles are presented.

Anticancer Potential of Biogenic Silver Nanoparticles: A Mechanistic Study

The continuous loss of human life due to the paucity of effective drugs against different forms of cancer demands a better/noble therapeutic approach. One possible way could be the use of nanostructures-based treatment methods. In the current piece of work, we have synthesized silver nanoparticles (AgNPs) using plant (Heliotropiumbacciferum) extract using AgNO3 as starting materials. The size, shape, and structure of synthesized AgNPs were confirmed by various spectroscopy and microscopic techniques. The average size of biosynthesized AgNPs was found to be in the range of 15 nm. The anticancer potential of these AgNPs was evaluated by a battery of tests such as MTT, scratch, and comet assays in breast (MCF-7) and colorectal (HCT-116) cancer models. The toxicity of AgNPs towards cancer cells was confirmed by the expression pattern of apoptotic (p53, Bax, caspase-3) and antiapoptotic (BCl-2) genes by RT-PCR. The cell viability assay showed an IC₅₀ value of 5.44 and 9.54 µg/mL for AgNPs in MCF-7 and HCT-116 cell lines respectively. We also observed cell migration inhibiting potential of AgNPs in a concentration-dependent manner in MCF-7 cell lines. A tremendous rise (150–250%) in the production of ROS was observed as a result of AgNPs treatment compared with control. Moreover, the RT-PCR results indicated the difference in expression levels of pro/antiapoptotic proteins in both cancer cells. All these results indicate that cell death observed by us is mediated by ROS production, which might have altered the cellular redox status. Collectively, we report the antimetastasis potential of biogenic synthesized AgNPs against breast and colorectal cancers. The biogenic synthesis of AgNPs seems to be a promising anticancer therapy with greater efficacy against the studied cell lines.

Nanoparticle delivery system, highly active antiretroviral therapy, and testicular morphology: The role of stereology

The conjugation of nanoparticles (NPs) with antiretroviral drugs is a drug delivery approach with great potential for managing HIV infections. Despite their promise, recent studies have highlighted the toxic effects of nanoparticles on testicular tissue and their impact on sperm morphology. This review explores the role of stereological techniques in assessing the testicular morphology in highly active antiretroviral therapy (HAART) when a nanoparticle drug delivery system is used. Also, NPs penetration and pharmacokinetics concerning the testicular tissue and blood-testis barrier form the vital part of this review. More so, various classes of NPs employed in biomedical and clinical research to deliver antiretroviral drugs were thoroughly discussed. In addition, considerations for minimizing nanoparticle-drugs toxicity, ensuring enhanced permeability of nanoparticles, maximizing drug efficacy, ensuring adequate bioavailability, and formulation of HAART-NPs fabrication are well discussed.

Perinatal exposure to silver nanoparticles reprograms immunometabolism and promotes pancreatic beta-cell death and kidney damage in mice

Silver nanoparticles (AgNPs) are extensively utilized in food, cosmetics, and healthcare products. Though the effects of AgNPs exposure on adults are well documented, the long-term effects of gestational/perinatal exposure upon the health of offspring have not been addressed. Herein, we show that only perinatal exposure to AgNPs through the mother could lead to chronic inflammation in offspring which persists till adulthood. Further, AgNPs exposure altered offspring's immune responses against environmental stresses. AgNPs exposed offspring showed an altered response in splenocyte proliferation assay when challenged to lipopolysaccharide, concanavalin-A, AgNPs, or silver ions. Perinatal AgNPs exposure affected metabolic parameters (resistin, glucagon-like peptide-1, leptin, insulin) and upregulated JNK/P38/ERK signaling in the pancreas. We observed pancreatic damage, reduced insulin level, and increased blood glucose levels. Further, we observed renal damage, particularly to tubular and glomerular regions as indicated by histopathology and electron microscopy. Our study thus shows that only perinatal exposure to AgNPs could induce persistent inflammation, alter immune responses against foreign antigens and metabolism which may contribute to pancreatic and renal damage later in life.

Chitosan-Based Nanoparticles Against Viral Infections

Viral infections, in addition to damaging host cells, can compromise the host immune system, leading to frequent relapse or long-term persistence. Viruses have the capacity to destroy the host cell while liberating their own RNA or DNA in order to replicate within additional host cells. The viral life cycle makes it challenging to develop anti-viral drugs. Nanotechnology-based approaches have been suggested to deal effectively with viral diseases, and overcome some limitations of anti-viral drugs. Nanotechnology has enabled scientists to overcome the challenges of solubility and toxicity of anti-viral drugs, and can enhance their selectivity towards viruses and virally infected cells, while preserving healthy host cells. Chitosan is a naturally occurring polymer that has been used to construct nanoparticles (NPs), which are biocompatible, biodegradable, less toxic, easy to prepare, and can function as effective drug delivery systems (DDSs). Furthermore, chitosan is Generally Recognized as Safe (GRAS) by the US Food and Drug Administration (U.S. FDA). Chitosan NPs have been used in drug delivery by the oral, ocular, pulmonary, nasal, mucosal, buccal, or vaginal routes. They have also been studied for gene delivery, vaccine delivery, and advanced cancer therapy. Multiple lines of evidence suggest that chitosan NPs could be used as new therapeutic tools against viral infections. In this review we summarize reports concerning the therapeutic potential of chitosan NPs against various viral infections.

Nanotechnology for virus treatment

The continued emergence of novel viruses poses a significant threat to global health. Uncontrolled outbreaks can result in pandemics that have the potential to overburden our healthcare and economic systems. While vaccination is a conventional modality that can be employed to promote herd immunity, antiviral vaccines can only be applied prophylactically and do little to help patients who have already contracted viral infections. During the early stages of a disease outbreak when vaccines are unavailable, therapeutic antiviral drugs can be used as a stopgap solution. However, these treatments do not always work against emerging viral strains and can be accompanied by adverse effects that sometimes outweigh the benefits. Nanotechnology has the potential to overcome many of the challenges facing current antiviral therapies. For example, nanodelivery vehicles can be employed to drastically improve the pharmacokinetic profile of antiviral drugs while reducing their systemic toxicity. Other unique nanomaterials can be leveraged for their virucidal or virus-neutralizing properties. In this review, we discuss recent developments in antiviral nanotherapeutics and provide a perspective on the application of nanotechnology to the SARS-CoV-2 outbreak and future virus pandemics.

All That Glitters Is Not Silver-A New Look at Microbiological and Medical Applications of Silver Nanoparticles

Silver and its nanoparticles (AgNPs) have different faces, providing different applications. In recent years, the number of positive nanosilver applications has increased substantially. It has been proven that AgNPs inhibit the growth and survival of bacteria, including human and animal pathogens, as well as fungi, protozoa and arthropods. Silver nanoparticles are known from their antiviral and anti-cancer properties; however, they are also very popular in medical and pharmaceutical nanoengineering as carriers for precise delivery of therapeutic compounds, in the diagnostics of different diseases and in optics and chemistry, where they act as sensors, conductors and substrates for various syntheses. The activity of AgNPs has not been fully discovered; therefore, we need interdisciplinary research to fulfil this knowledge. New forms of products with silver will certainly find application in the future treatment of many complicated and difficult to treat diseases. There is still a lack of appropriate and precise legal condition regarding the circulation of nanomaterials and the rules governing their safety use. The relatively low toxicity, relative biocompatibility and selectivity of nanoparticle interaction combined with the unusual biological properties allow their use in animal production as well as in bioengineering and medicine. Despite a quite big knowledge on this topic, there is still a need to organize the data on AgNPs in relation to specific microorganisms such as bacteria, viruses or fungi. We decided to put this knowledge together and try to show positive and negative effects on prokaryotic and eukaryotic cells.

Inorganic and Polymeric Nanoparticles for Human Viral and Bacterial Infections Prevention and Treatment

Infectious diseases hold third place in the top 10 causes of death worldwide and were responsible for more than 6.7 million deaths in 2016. Nanomedicine is a multidisciplinary field which is based on the application of nanotechnology for medical purposes and can be defined as the use of nanomaterials for diagnosis, monitoring, control, prevention, and treatment of diseases, including infectious diseases. One of the most used nanomaterials in nanomedicine are nanoparticles, particles with a nano-scale size that show highly tunable physical and optical properties, and the capacity to a wide library of compounds. This manuscript is intended to be a comprehensive review of the available recent literature on nanoparticles used for the prevention and treatment of human infectious diseases caused by different viruses, and bacteria from a clinical point of view by basing on original articles which talk about what has been made to date and excluding commercial products, but also by highlighting what has not been still made and some clinical concepts that must be considered for futures nanoparticles-based technologies applications.

New Textile for Personal Protective Equipment—Plasma Chitosan/Silver Nanoparticles Nylon Fabric

Fabric structures are prone to contamination with microorganisms, as their morphology and ability to retain moisture creates a proper environment for their growth. In this work, a novel, easily processed and cheap coating for a nylon fabric with antimicrobial characteristics was developed. After plasma treatment, made to render the fabric surface more reactive sites, the fabric was impregnated with chitosan and silver nanoparticles by simply dipping it into a mixture of different concentrations of both components. Silver nanoparticles were previously synthesized using the Lee–Meisel method, and their successful obtention was proven by UV–Vis, showing the presence of the surface plasmon resonance band at 410 nm. Nanoparticles with 25 nm average diameter observed by STEM were stable, mainly in the presence of chitosan, which acted as a surfactant for silver nanoparticles, avoiding their aggregation. The impregnated fabric possessed bactericidal activity higher for Gram-positive Staphylococcus aureus than for Gram-negative Pseudomonas aeruginosa bacteria for all combinations. The percentage of live S. aureus and P. aeruginosa CFU was reduced to less than 20% and 60%, respectively, when exposed to each of the coating combinations. The effect was more pronounced when both chitosan and silver were present in the coating, suggesting an effective synergy between these components. After a washing process, the antimicrobial effect was highly reduced, suggesting that the coating is unstable after washing, being almost completely removed from the fabric. Nevertheless, the new-coated fabric can be successfully used in single-use face masks. To our knowledge, the coating of nylon fabrics intended for face-mask material with both agents has never been reported.

Silver nanoparticles: synthesis, characterisation and biomedical applications

Nanotechnology is a rapidly growing field due to its unique functionality and a wide range of applications. Nanomedicine explores the possibilities of applying the knowledge and tools of nanotechnology for the prevention, treatment, diagnosis and control of disease. In this regard, silver nanoparticles with diameters ranging from 1 to 100 nm are considered most important due to their unique properties, ability to form diverse nanostructures, their extraordinary range of bactericidal and anticancer properties, wound healing and other therapeutic abilities and their cost-effectiveness in production. The current paper reviews various types of physical, chemical and biological methods used in the production of silver nanoparticles. It also describes approaches employing silver nanoparticles as antimicrobial and antibiofilm agents, as antitumour agents, in dentistry and dental implants, as promoters of bone healing, in cardiovascular implants and as promoters of wound healing. The paper also explores the mechanism of action, synthesis methods and morphological characterisation of silver nanoparticles to examine their role in medical treatments and disease management.

Inorganic nanomaterials for fighting surface and airborne pathogens and viruses

Nowadays, the deadly viruses (including the latest coronavirus) and pathogens transmission became the major concern worldwide. Efforts have been made to combat with these fatal germs transmitted by the airborne, human-to-human contacts and contaminated surfaces. Thus, the antibacterial and antiviral materials have been widely researched. Meanwhile, the development of diverse nanomaterials with the antiviral traits provided several benefits to counter the threats from the surface and airborne viruses especially during the Covid-19 pandemic. Based on these facts, this paper overviewed the advantages of various nanomaterials that can disinfect and deactivate different lethal viruses transmitted through the air and surfaces. The past development, recent progress, future trends, environmental impacts, biocidal effects and prospects of these nanomaterials for the antiviral coating applications have been emphasized.

Nano Antiviral Photodynamic Therapy: a Probable Biophysicochemical Management Modality in SARS-CoV-2

INTRODUCTION

COVID-19 disease has shocked the world by its spread and contagiousness. At this time, there is no valid vaccine and no proven drug treatment for COVID-19 patients. Current treatments are focused on Oxygenation, Cytokine Storm management, anti-inflammatory effects, and antiviral therapy. Antiviral photodynamic therapy (aPDT) is based on the reaction between a photo-sensitive agent and a light source in the presence of oxygen which can produce oxidative and free radical agents to damage the virus' structures. Recent studies show that nanotechnology can improve aPDT's outcome. The aim of this study was to find out the potential therapeutic effects of Nano antiviral photodynamic therapy on COVID-19.

AREAS COVERED

This review evaluates Nano Antiviral Photodynamic Therapy: A Probable Biophysicochemical Management Modality in SARS-CoV-2. Data were extracted from published different studies published on PUBMED, SCOPUS, and Web of Science.

EXPERT OPINION

Studies indicating that aPDT and Nano-based aPDT can be useful in viral pulmonary complications like Influenza, SARS-CoV, and MERS, but there was no direct study on SARS-Cov-2. Recent studies showed that Nano-based aPDT could relate to control of the stages of viral infections. Altogether, further investigations for the application of nanomedicine in antimicrobial photodynamic inactivation are needed for COVID-19 Management.

Toxicological alterations induced by subacute exposure of silver nanoparticles in Wistar rats

Silver nanoparticles (AgNPs) have become crucial players in the field of medicine and various other industries. AgNPs have a wide array of applications, which includes production of electronic goods, cosmetics, synthesis of dyes, and printing inks, as well as targeted delivery of drugs to specialized cells inside the body. Even though humans readily come in contact with these particles, the organ-specific accumulation and resulting mechanisms of toxicity induced by inhaled AgNPs are still under investigation. The goal of this study was to determine the organ distribution of inhaled AgNPs and investigate the resulting systemic toxicity. To do this, male Wistar rats were exposed by inhalation to AgNPs for 4 hr/day (200 parts per billion/day) for five consecutive days. The nanoparticles were generated using a laser ablation technique using a soft-landing ion mobility (SLIM) instrument. Inductively coupled plasma mass spectrometric (ICP-MS) analysis showed organ-specific accumulation of the nanoparticles, with the highest concentration present in the lungs, followed by the liver and kidneys. Nanoparticle distribution was characterized in the organs using scanning electron microscopy (SEM) and matrix-assisted laser desorption/ionization mass spectrometric (MALDI-MS) imaging. Bone marrow cytotoxicity assay of the cells from the femur of rats showed micronuclei formation and signs of cellular cytotoxicity. Moreover, rats displayed increased levels of circulating lactate and glutathione disulphide (GSSG), as determined by liquid chromatography-mass spectrometry (LC-MS) analysis. Collectively, our observations suggest that inhaled subacute exposure to AgNP results in accumulation of AgNPs in the lungs, liver, and kidneys, preferentially, as well as mediates induced systemic toxicity.

Targeted silver nanoparticles for rheumatoid arthritis therapy via macrophage apoptosis and Re-polarization

Infiltration of inflammatory cells, especially the M1 macrophages that secrete various types of inflammation cytokines, play crucial roles in the pathogenesis of rheumatoid arthritis (RA). To relief synovial inflammation, M1 macrophages must be eliminated or switched to anti-inflammatory M2 phenotype. We herein developed folic acid modified silver nanoparticles (FA-AgNPs) that can actively deliver into M1 macrophages to synergistically induce M1 macrophages reduction and M2 macrophages polarization for effective RA treatment. The AgNPs was facilely prepared, PEGylated and modified with FA to realize M1 macrophages targeting delivery via folate receptor overexpressed on M1 macrophages surface. After entering cells, FA-AgNPs dissolved and released Ag⁺ in response to intracellular glutathione (GSH), which is the key element to exert a series of anti-inflammatory functions, such as M1 macrophages apoptosis and reactive oxygen species (ROS) scavenging to facilitate M2 macrophages polarization, both of which contributed to RA treatment. This nano-system could passively accumulate into inflamed joints, permit potent anti-inflammatory activity, and impose strong therapeutic efficacy in mice RA models with high biosafety. After treatment, FA-AgNPs could be gradually cleared from the body mainly via feces without tissue accumulation, and did not show any appreciable long-term toxicity. This work declares the first example of using bio-active nanoparticles for RA treatment without loading any drugs, and highlights the potential of FA-AgNPs for targeted RA therapy via simultaneous M1 macrophage apoptosis and M1-to-M2 macrophages re-polarization.