Nanoparticle composite TPNT1 is effective against SARS-CoV-2 and influenza viruses

Golden Therapeutic Approach to Combat Viral Diseases Using Gold Nanomaterials

Gold nanoparticles (AuNPs), due to their unique properties and surface modification abilities, have become a promising carrier for a range of biomedical applications. AuNPs have intrinsic antiviral characteristics because of their capacity to enhance drug distribution by making antiviral medications more stable and soluble, which assures that higher quantities reach the intended site. Through surface changes, AuNPs can bind directly to viral particles or infected cells, increasing therapeutic efficiency and reducing side effects. AuNPs efficiently damage cell membranes and hinder viral reproduction within a host cell. Furthermore, because of their large surface area-to-volume ratio, which enables many functional groups to connect, improving interaction with virus particles and ceasing their multiplication. By altering dimensions and morphology or conjugating it with additional antiviral drugs, AuNPs can array their synergistic antiviral activity. Thus, the development of AuNP conjugated therapy presents a promising avenue to address the demand for novel anti-viral therapeutics against infections resistant to several drugs.

Enhanced and copper concentration dependent virucidal effect against SARS-CoV-2 of electrospun poly(vinylidene difluoride) filter materials

Virucidal filter materials were prepared by electrospinning a solution of 28 wt % poly(vinylidene difluoride) in N,N-dimethylacetamide without and with the addition of 0.25 wt %, 0.75 wt %, 2.0 wt %, or 3.5 wt % Cu(NO3)2 · 2.5H2O as virucidal agent. The fabricated materials had a uniform and defect free fibrous structure and even distribution of copper nanoclusters. X-ray diffraction analysis showed that during the electrospinning process, Cu(NO3)2 · 2.5H2O changed into Cu2(NO3)(OH)3. Electrospun filter materials obtained by electrospinning were essentially macroporous. Smaller pores of copper nanoclusters containing materials resulted in higher particle filtration than those without copper nanoclusters. Electrospun filter material fabricated with the addition of 2.0 wt % and 3.5 wt % of Cu(NO3)2 · 2.5H2O in a spinning solution showed significant virucidal activity, and there was 2.5 ± 0.35 and 3.2 ± 0.30 logarithmic reduction in the concentration of infectious SARS-CoV-2 within 12 h, respectively. The electrospun filter materials were stable as they retained virucidal activity for three months.

Natural fucoidans inhibit coronaviruses by targeting viral spike protein and host cell furin

Fucoidans are a class of long chain sulfated polysaccharides and have multiple biological functions. Herein, four natural fucoidans extracted from Fucus vesiculosus, F. serratus, Laminaria japonica and Undaria pinnatifida, were tested for their HCoV-OC43 inhibition and found to demonstrate EC50 values ranging from 0.15 to 0.61 µg/mL. That from U. pinnatifida exhibited the most potent anti-HCoV-OC43 activity with an EC50 value of 0.15 ± 0.02 µg/mL, a potency largely independent of its sulfate content. Comparison of the gene expression profiles of fucoidan-treated and untreated cells infected with HCoV-OC43 revealed that fucoidan treatment effectively diminished HCoV-OC43 gene expressions associated with induced chemokines, cytokines and viral activities. Further studies using a highly fucoidan-resistant HCoV-OC43 determined that fucoidan inhibited HCoV-OC43 infection via interfering with viral entry and led to the identification of the specific site on the N-terminal region of spike protein, that located adjacent to the host cell receptor binding domain, targeted by the virus. Furthermore, in a SARS-CoV-2 pseudovirus neutralization assay, fucoidan also blocked SARS-CoV-2 entry. In vitro and in vivo, fucoidan decreased SARS-CoV-2 viral loads and inhibited viral infection in Calu-3 or Vero E6 cells and SARS-CoV-2 infected hamsters, respectively. Fucoidan was also found to inhibit furin activity, and reported furin inhibitors were found to inhibit viral infection by wild type HCoV-OC43 or SARS-CoV-2. Accordingly, we conclude that fucoidans inhibit coronaviral infection by targeting viral spike protein and host cell furin to interfere with viral entry.

Organic-Inorganic Hybrid Nanocomposites for Nanotheranostics: Special Focus on Preventing Emerging Variants of SARS-COV-2

The worldwide emerging cases of various respiratory viral diseases and the current escalation of novel coronavirus disease (COVID-19) make people considerably attentive to controlling these viruses through innovative methods. Most re-emerging respiratory diseases envelop RNA viruses that employ attachment between the virus and host cell to get an entry form using the host cell machinery. Emerging variants of COVD-19 also bring about a constant threat to public health as it has wide infectivity and can quickly spread to infect humans. This review focuses on insights into the current investigations to prevent the progression of incipient variants of Severe Acute Respiratory Syndrome Coronavirus (SARS-COV-2) along with similar enveloped RNA viruses that cause respiratory illness in humans and animals. Nanotheranostics is a trailblazing arena of nanomedicine that simultaneously helps prevent or treat diseases and diagnoses. Nanoparticle coating and nanofibers were extensively explored, preventing viral contaminations. Several studies have proven the virucidal activities of metal nanoparticles like copper, silver, and titanium against respiratory viral pathogens. Worldwide many researchers have shown surfaces coated with ionic nanoparticles like zinc or titanium act as potent antiviral agents against RNA viruses. Carbon nanotubes, quantum dots, silica nanoparticles (NPs), polymeric and metallic nanoparticles have also been explored in the field of nanotheranostics in viral detection. In this review, we have comprehensively discussed different types of metallic, ionic, organic nanoparticles and their hybrids showing substantial antiviral properties to stop the progression of the novel coronavirus disease focused on three key classes: prevention, diagnostics, and treatment.

Biomimetic SARS-CoV-2 Spike Protein Nanoparticles

COVID-19 is an infectious respiratory disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This virus contains a crucial coat protein that engages with target cells via a receptor binding domain (RBD) on its spike protein. To better study the RBD and its therapeutic opportunities, we genetically engineered a simple fusion with a thermo-responsive elastin-like polypeptide (ELP). These fusions express in Escherichia coli at a high yield in the soluble fraction and were easily purified using ELP-mediated phase separation (79 mg/L culture). Interestingly, they assembled peptide-based nanoparticles (Rh = 71.4 nm), which was attributed to oligomerization of RBDs (25.3 kDa) counterbalanced by steric stabilization by a soluble ELP (73.4 kDa). To investigate their biophysical properties, we explored the size, shape, and binding affinity for the human angiotensin-converting enzyme 2 (hACE2) and cellular uptake. Biomimetic nanoparticles such as these may enable future strategies to target the same cells, tissues, and cell-surface receptors as those harnessed by SARS-CoV-2.

Identification of diphenylurea derivatives as novel endocytosis inhibitors that demonstrate broad-spectrum activity against SARS-CoV-2 and influenza A virus both in vitro and in vivo

Rapid evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza A virus (IAV) poses enormous challenge in the development of broad-spectrum antivirals that are effective against the existing and emerging viral strains. Virus entry through endocytosis represents an attractive target for drug development, as inhibition of this early infection step should block downstream infection processes, and potentially inhibit viruses sharing the same entry route. In this study, we report the identification of 1,3-diphenylurea (DPU) derivatives (DPUDs) as a new class of endocytosis inhibitors, which broadly restricted entry and replication of several SARS-CoV-2 and IAV strains. Importantly, the DPUDs did not induce any significant cytotoxicity at concentrations effective against the viral infections. Examining the uptake of cargoes specific to different endocytic pathways, we found that DPUDs majorly affected clathrin-mediated endocytosis, which both SARS-CoV-2 and IAV utilize for cellular entry. In the DPUD-treated cells, although virus binding on the cell surface was unaffected, internalization of both the viruses was drastically reduced. Since compounds similar to the DPUDs were previously reported to transport anions including chloride (Cl-) across lipid membrane and since intracellular Cl- concentration plays a critical role in regulating vesicular trafficking, we hypothesized that the observed defect in endocytosis by the DPUDs could be due to altered Cl- gradient across the cell membrane. Using in vitro assays we demonstrated that the DPUDs transported Cl- into the cell and led to intracellular Cl- accumulation, which possibly affected the endocytic machinery by perturbing intracellular Cl- homeostasis. Finally, we tested the DPUDs in mice challenged with IAV and mouse-adapted SARS-CoV-2 (MA 10). Treatment of the infected mice with the DPUDs led to remarkable body weight recovery, improved survival and significantly reduced lung viral load, highlighting their potential for development as broad-spectrum antivirals.

The anti SARS-CoV-2 activity of nanofibrous filter materials activated with metal clusters

Nanofibrous filter materials were prepared by electrospinning a solution of 28 wt% poly(vinylidene fluoride) in N,N-dimethylacetamide with and without the addition of 2 wt% AgNO₃, Cu(NO₃)₂·2.5H₂O or ZnCl₂. X-ray diffraction, scanning electron microscopy with energy dispersive X-ray spectroscopy, inductively coupled plasma mass spectroscopy, thermogravimetric analysis, contact angle measurement, nitrogen sorption, and mercury intrusion porosimetry methods were used for the characterization of physical structure as well as the chemical composition of the electrospun materials. Particle filtration efficiency and antiviral activity against the SARS-CoV-2 alpha variant were tested in order to estimate the suitability of the prepared electrospun filter materials for application as indoor air filtration systems with virucidal properties. All filter materials prepared with salts demonstrated very high particle filtration efficiency (≥98.0%). The best antiviral activity was demonstrated by a material containing Cu(NO₃)₂·2.5H₂O in the spinning solution, which displayed the decrease in the number of infectious virions by three orders of magnitude after a contact time of 12 h. Materials with the addition of AgNO₃ and ZnCl₂ decreased the number of infectious virions after the same contact time by only ∼8 and ∼11 times, respectively.

Delta SARS-CoV-2 inactivation and bactericidal performance of cotton wipes decorated with TiO2/Ag nanoparticles like Brazilian heavy-fruited Myrciaria cauliflora

The current pandemic of Coronavirus Disease 2019 (COVID-19) raised several concerns about using conventional textiles for manufacturing personal protective equipment without self-disinfecting properties since the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is transmitted mainly by aerosols that can transpose cotton masks. Therefore, developing new cotton fibers with high self-disinfecting ability is essential to avoid a new pandemic due to new SARS-CoV-2 variants. Herein, we developed cotton wipes (CFs) with fibers coated by Ag, TiO₂, and Ag/TiO₂ hybrid nanoparticles like Brazilian heavy-fruited Myrciaria cauliflora by a sonochemical approach. Moreover, the coated CFs present high antimicrobial performance against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), being able to inactivate infectious SARS-CoV-2 (Delta variant) by the destruction of the spike, membrane, and nucleocapsid proteins while the viral RNA is not significantly affected, according to the molecular biological findings.

Nanomaterials to combat SARS-CoV-2: Strategies to prevent, diagnose and treat COVID-19

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the associated coronavirus disease 2019 (COVID-19), which severely affect the respiratory system and several organs and tissues, and may lead to death, have shown how science can respond when challenged by a global emergency, offering as a response a myriad of rapid technological developments. Development of vaccines at lightning speed is one of them. SARS-CoV-2 outbreaks have stressed healthcare systems, questioning patients care by using standard non-adapted therapies and diagnostic tools. In this scenario, nanotechnology has offered new tools, techniques and opportunities for prevention, for rapid, accurate and sensitive diagnosis and treatment of COVID-19. In this review, we focus on the nanotechnological applications and nano-based materials (i.e., personal protective equipment) to combat SARS-CoV-2 transmission, infection, organ damage and for the development of new tools for virosurveillance, diagnose and immune protection by mRNA and other nano-based vaccines. All the nano-based developed tools have allowed a historical, unprecedented, real time epidemiological surveillance and diagnosis of SARS-CoV-2 infection, at community and international levels. The nano-based technology has help to predict and detect how this Sarbecovirus is mutating and the severity of the associated COVID-19 disease, thereby assisting the administration and public health services to make decisions and measures for preparedness against the emerging variants of SARS-CoV-2 and severe or lethal COVID-19.

Nanoscale Technologies in the Fight against COVID-19: From Innovative Nanomaterials to Computer-Aided Discovery of Potential Antiviral Plant-Derived Drugs

The last few years have increasingly emphasized the need to develop new active antiviral products obtained from artificial synthesis processes using nanomaterials, but also derived from natural matrices. At the same time, advanced computational approaches have found themselves fundamental in the repurposing of active therapeutics or for reducing the very long developing phases of new drugs discovery, which represents a real limitation, especially in the case of pandemics. The first part of the review is focused on the most innovative nanomaterials promising both in the field of therapeutic agents, as well as measures to control virus spread (i.e., innovative antiviral textiles). The second part of the review aims to show how computer-aided technologies can allow us to identify, in a rapid and therefore constantly updated way, plant-derived molecules (i.e., those included in terpenoids) potentially able to efficiently interact with SARS-CoV-2 cell penetration pathways.

Effects of Boswellia species on viral infections with particular attention to SARS-CoV-2

The emergence of pathogenic viruses is a worldwide frequent cause of diseases and, therefore, the design of treatments for viral infections stands as a significant research topic. Despite many efforts, the production of vaccines is faced with many obstacles and the high rate of viral resistance caused a severe reduction in the efficacy of antiviral drugs. However, the attempt of developing novel natural drugs, as well as the exertion of medicinal plants, may be an applicable solution for the treatment of viral diseases. Boswellia species exhibited a wide range of pharmacological activities in various conditions such as bronchial asthma, rheumatism, and Crohn’s illness. Additionally, pharmacological studies reported the observance of practical antiviral activities from different parts of this substance, especially the oleo-gum-resin. Therefore, this work provided an overview on the antiviral properties of Boswellia species and their potential therapeutic effects in the field of COVID-19 pandemic.

Enzyme Nanoscale Interactions with Manganese Zinc Sulfide Give Insight into Potential Antiviral Mechanisms and SARS-CoV-2 Inhibition

Recent interest in nanomedicine has skyrocketed because of mRNA vaccine lipid nanoparticles (LNPs) against COVID-19. Ironically, despite this success, the innovative nexus between nanotechnology and biochemistry, and the impact of nanoparticles on enzyme biochemical activity is poorly understood. The studies of this group on zinc nanoparticle (ZNP) compositions suggest that nanorod morphologies are preferred and that ZNP doped with manganese or iron can increase activity against model enzymes such as luciferase, DNA polymerase, and β-galactosidase (β-Gal), with the latter previously being associated with antimicrobial activity. SARS-CoV-2 encodes several of these types of oxido-reductase, polymerase, or hydrolase types of enzymes, and while metamaterials or nanoparticle composites have become important in many fields, their application against SARS-CoV-2 has only recently been considered. Recently, this group discovered the antiviral activity of manganese-doped zinc sulfide (MnZnS), and here the interactions of this nanoparticle composite with β-Gal, angiotensin converting enzyme (ACE), and human ACE2 (hACE2), the SARS-CoV-2 receptor, are demonstrated. Low UV, circular dichroism, and zeta potential results confirm their enzyme interaction and inhibition by fluorometric area under the curve (AUC) measurements. The IC₅₀ of enzyme activity varied depending on the manganese percentage and surface ranging from 20 to 50 μg/mL. MnZnS NPs give a 1–2 log order inhibition of SARS-CoV-2; however, surface-capping with cysteine does not improve activity. These data suggest that Mn substituted ZNP interactions to hACE2 and potentially other enzymes may underlie its antiviral activity, opening up a new area of pharmacology ready for preclinical translation.

Exploring the Role of Heavy Metals and Their Derivatives on the Pathophysiology of COVID-19

Many aspects of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its disease, COVID-19, have been studied to determine its properties, transmission mechanisms, and pathology. These efforts are aimed at identifying potential approaches to control or treat the disease. Early treatment of novel SARS-CoV-2 infection to minimize symptom progression has minimal evidence; however, many researchers and firms are working on vaccines, and only a few vaccines exist. COVID-19 is affected by several heavy metals and their nanoparticles. We investigated the effects of heavy metals and heavy metal nanoparticles on SARS-CoV-2 and their roles in COVID-19 pathogenesis. AgNPs, AuNPs, gold-silver hybrid NPs, copper nanoparticles, zinc oxide, vanadium, gallium, bismuth, titanium, palladium, silver grafted graphene oxide, and some quantum dots were tested to see if they could minimize the severity or duration of symptoms in patients with SARS-CoV-2 infection when compared to standard therapy.

Zinc associated nanomaterials and their intervention in emerging respiratory viruses: Journey to the field of biomedicine and biomaterials

Respiratory viruses represent a severe public health risk worldwide, and the research contribution to tackle the current pandemic caused by the SARS-CoV-2 is one of the main targets among the scientific community. In this regard, experts from different fields have gathered to confront this catastrophic pandemic. This review illustrates how nanotechnology intervention could be valuable in solving this difficult situation, and the state of the art of Zn-based nanostructures are discussed in detail. For virus detection, learning from the experience of other respiratory viruses such as influenza, the potential use of Zn nanomaterials as suitable sensing platforms to recognize the S1 spike protein in SARS-CoV-2 are shown. Furthermore, a discussion about the antiviral mechanisms reported for ZnO nanostructures is included, which can help develop surface disinfectants and protective coatings. At the same time, the properties of Zn-based materials as supplements for reducing viral activity and the recovery of infected patients are illustrated. Within the scope of noble adjuvants to improve the immune response, the ZnO NPs properties as immunomodulators are explained, and potential prototypes of nanoengineered particles with metallic cations (like Zn2+) are suggested. Therefore, using Zn-associated nanomaterials from detection to disinfection, supplementation, and immunomodulation opens a wide area of opportunities to combat these emerging respiratory viruses. Finally, the attractive properties of these nanomaterials can be extrapolated to new clinical challenges.

Potential Application of Bionanoparticles to Treat Severe Acute Respiratory Syndrome Coronavirus-2 Infection

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a contagious virus that spreads exponentially across the world, resulting in serious viral pneumonia. Several companies and researchers have put their tremendous effort into developing novel vaccines or drugs for the complete eradication of COVID-19 caused by SARS-CoV-2. Bionanotechnology plays a vital role in designing functionalized biocompatible nanoparticulate systems with higher antiviral capabilities. Thus, several nanocarriers have been explored in designing and delivering drugs and vaccines. This problem can be overcome with the intervention of biomaterials or bionanoparticles. The present review describes the comparative analysis of SARS infection and its associated etiological agents. This review also highlighted some nanoparticles that have been explored in the treatment of COVID-19. However, these carriers elicit several problems once they come in contact with biological systems. Often, the body’s immune system treats these nanocarriers as foreign particles and antigens. In contrast, some bionanoparticles are highlighted here with their potential application in SARS-CoV-2. However, bionanoparticles have demonstrated some drawbacks discussed here with the possible outcomes. The scope of bioinspired nanoparticles is also discussed in detail to explore the new era of research. It is highly essential for the effective delivery of these nanoparticles to the target site. For effective management of SARS-CoV-2, different delivery patterns are also discussed here.

Past and Current Progress in the Development of Antiviral/Antimicrobial Polymer Coating towards COVID-19 Prevention: A Review

The astonishing outbreak of SARS-CoV-2 coronavirus, known as COVID-19, has attracted numerous research interests, particularly regarding fabricating antimicrobial surface coatings. This initiative is aimed at overcoming and minimizing viral and bacterial transmission to the human. When contaminated droplets from an infected individual land onto common surfaces, SARS-CoV-2 coronavirus is able to survive on various surfaces for up to 9 days. Thus, the possibility of virus transmission increases after touching or being in contact with contaminated surfaces. Herein, we aim to provide overviews of various types of antiviral and antimicrobial coating agents, such as antimicrobial polymer-based coating, metal-based coating, functional nanomaterial, and nanocomposite-based coating. The action mode for each type of antimicrobial agent against pathogens is elaborated. In addition, surface properties of the designed antiviral and antimicrobial polymer coating with their influencing factors are discussed in this review. This paper also exhibits several techniques on surface modification to improve surface properties. Various developed research on the development of antiviral/antimicrobial polymer coating to curb the COVID-19 pandemic are also presented in this review.

Nanotechnology-based therapeutic formulations in the battle against animal coronaviruses: an update

Outbreak of infectious diseases imposes a serious threat to human population and also causes a catastrophic impact on global economy. Animal coronaviruses remain as one of the intriguing problems, known to cause deadly viral diseases on economically important animal population, and also these infections may spread to other animals and humans. Through isolation of the infected animals from others and providing appropriate treatment using antiviral drugs, it is possible to prevent the virus transmission from animals to other species. In recent times, antiviral drug-resistant strains are being emerged as a deadly virus which are known to cause pandemic. To overcome this, nanoparticles-based formulations are developed as antiviral agent which attacks the animal coronaviruses at multiple sites in the virus replication cycle. Nanovaccines are also being formulated to protect the animals from coronaviruses. Nanoformulations contain particles of one or more dimensions in nano-scale (few nanometers to 1000 nm), which could be inorganic or organic in nature. This review presents the comprehensive outline of the nanotechnology-based therapeutics formulated against animal coronaviruses, which includes the nanoparticles-based antiviral formulations and nanoparticles-based adjuvant vaccines. The mechanism of action of these nanoparticles-based antivirals against animal coronavirus is also discussed using relevant examples. In addition, the scope of repurposing the existing nano-enabled antivirals and vaccines to combat the coronavirus infections in animals is elaborated.

Effective SARS-CoV-2 antiviral activity of hyperbranched polylysine nanopolymers

The coronavirus pandemic (COVID-19) had spread rapidly since December 2019, when it was first identified in Wuhan, China. As of April 2021, more than 130 million cases have been confirmed, with more than 3 million deaths, making it one of the deadliest pandemics in history. Different approaches must be put in place to confront a new pandemic: community-based behaviours (i.e., isolation and social distancing), antiviral treatments, and vaccines. Although behaviour-based actions have produced significant benefits and several efficacious vaccines are now available, there is still an urgent need for treatment options. Remdesivir represents the first antiviral drug approved by the Food and Drug Administration for COVID-19 but has several limitations in terms of safety and treatment benefits. There is still a strong request for other effective, safe, and broad-spectrum antiviral systems in light of future emergent coronaviruses. Here, we describe a polymeric nanomaterial derived from L-lysine, with an antiviral activity against SARS-CoV-2 associated with a good safety profile in vitro. Nanoparticles of hyperbranched polylysine, synthesized by L-lysine's thermal polymerization catalyzed by boric acid, effectively inhibit the SARS-CoV-2 replication. The virucidal activity is associated with the charge and dimension of the nanomaterial, favouring the electrostatic interaction with the viral surface being only slightly larger than the virions' dimensions. Low-cost production and easiness of synthesis strongly support the further development of such innovative nanomaterials as a tool for potential treatments of COVID-19 and, in general, as broad-spectrum antivirals.