An overview of functional nanoparticles as novel emerging antiviral therapeutic agents

Modifying cellulose fibres with carbon dots: a promising approach for the development of antimicrobial fibres

This study focuses on the development of antimicrobial fibres for use in medical and healthcare textile industries. Carbon dots (CDs) were designed with boronic acid groups for the attachment to cellulose fibres found in cotton textiles and to enhance their attachment to glycogens on bacterial surfaces. Boronic acid-based and curcumin-based CDs were prepared and characterized using various techniques, showing a nanoscale size and zeta potential values. The CDs inhibited the growth of both Staphylococcus epidermidis and Escherichia coli bacteria, with UV-activated CDs demonstrating improved antibacterial activity. The antimicrobial activity of the CDs was then tested, revealing strong adherence to cellulose paper fibres with no CD diffusion and potent inhibition of bacterial growth. Cytotoxicity assays on human cell lines showed no toxicity towards cells at concentrations of up to 100 µg ml-1 but exhibited increased toxicity at concentrations exceeding 1000 µg ml-1. However, CD-modified cellulose paper fibres showed no toxicity against human cell lines, highlighting the antimicrobial properties of the CD-modified cellulose fibres are safe for human use. These findings show promising potential for applications in both industrial and clinical settings.

Nanoparticle‑based antiviral strategies to combat the influenza virus (Review)

The rapid availability of effective antiviral treatments would be beneficial during the early phases of a pandemic, as they could reduce viral loads and control serious infections until antigenic vaccines become widely available. One promising alternative therapy to combat pandemics is nanotechnology, which has the potential to inhibit a wide variety of viruses, including the influenza virus. This review summarizes the recent progress using gold, copper, silver, silicone, zinc and selenium nanoparticles, since these materials have shown remarkable antiviral capacity against influenza A virus.

Development and Fabrication of a Molecularly Imprinted Polymer-Based Electroanalytical Sensor for the Determination of Acyclovir

Acyclovir (ACV), a synthetic nucleoside derivative of purine, is one of the most potent antiviral medications recommended in the specific management of varicella-zoster and herpes simplex viruses. The molecularly imprinted polymer (MIP) was utilized to create an effective and specific electrochemical sensor using a straightforward photopolymerization process to determine ACV. The polymeric thin coating was developed using the template molecule ACV, a functional monomer acrylamide, a basic monomer 2-hydroxyethyl methacrylate, a cross-linker ethylene glycol dimethacrylate, and a photoinitiator 2-hydroxy-2-methyl propiophenone on the exterior of the glassy carbon electrode (GCE). Scanning electron microscopy, attenuated total reflectance-Fourier transform infrared spectroscopy, electrochemical impedance spectroscopy, and cyclic voltammetry were employed for the purpose of characterizing the constructed sensor (AM-ACV@MIP/GCE). Differential pulse voltammetry and a 5 mM ferrocyanide/ferricyanide ([Fe(CN)6]3-/4-) redox reagent were used to detect the ACV binding to the specific cavities on MIP. The study involves density functional theory (DFT) calculations, which were conducted to investigate template-functional monomer interactions thoroughly, calculate template-functional monomer interaction energies, and determine the optimal template/functional monomer ratio. DFT calculations were performed using Becke's three-parameter hybrid functional with the Lee-Yang-Parr correlation functional (B3LYP) method and 6-31G(d,p) basis set. The sensor exhibits linear performance throughout the concentration region 1 × 10-11 to 1 × 10-10 M, and the limit of detection and limit of quantification were 7.15 × 10-13 M and 2.38 × 10-12 M, respectively. For the electrochemical study of ACV, the sensor demonstrated high accuracy, precision, robustness, and a short detection time. Furthermore, the developed electrochemical sensor exhibited exceptional recovery in tablet dosage form and commercial human blood samples, with recoveries of 99.40 and 100.44%, respectively. The findings showed that the AM-ACV@MIP/GCE sensor would effectively be used to directly assess pharmaceuticals from actual specimens and would particularly detect ACV compared to structurally similar pharmaceutical compounds.

Nanomedicine approaches against SARS-CoV-2 and variants

The world is grappling with the ongoing crisis of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), a global pandemic that continues to have a detrimental impact on public health and economies worldwide. The virus's relentless mutation has led to more transmissible, immune-evasive strains, thereby escalating the incidence of reinfection. This underscores the urgent need for highly effective and safe countermeasures against SARS-CoV-2 and its evolving variants. In the current context, nanomedicine presents an innovative and promising alternative to mitigate the impacts of this pandemic wave. It does so by harnessing the structural and functional properties at a nanoscale in a straightforward and adaptable manner. This review emphasizes the most recent progress in the development of nanovaccines, nanodecoys, and nanodisinfectants to tackle SARS-CoV-2 and its variants. Notably, the insights gained and strategies implemented in managing the ongoing pandemic may also offer invaluable guidance for the development of potent nanomedicines to combat future pandemics.

The Interplay of Genital Herpes with Cellular Processes: A Pathogenesis and Therapeutic Perspective

Genital herpes, primarily caused by herpes simplex virus-2 (HSV-2), remains a pressing global health concern. Its remarkable ability to intertwine with cellular processes, from harnessing host machinery for replication to subverting antiviral defenses like autophagy and programmed cell death, exemplifies the intricate interplay at the heart of its pathogenesis. While the biomedical community has extensively researched antiviral interventions, the efficiency of these strategies in managing HSV-2 remains suboptimal. Recognizing this, attention has shifted toward leveraging host cellular components to regulate HSV-2 replication and influence the cell cycle. Furthermore, innovative interventional strategies-including drug repurposing, microbivacs, connecting the host microbiome, and exploiting natural secondary metabolites-are emerging as potential game changers. This review summarizes the key steps in HSV-2 pathogenesis and newly discovered cellular interactions, presenting the latest developments in the field, highlighting existing challenges, and offering a fresh perspective on HSV-2's pathogenesis and the potential avenues for its treatment by targeting cellular proteins and pathways.

Current Overview of Metal Nanoparticles' Synthesis, Characterization, and Biomedical Applications, with a Focus on Silver and Gold Nanoparticles

Metal nanoparticles (NPs) have garnered considerable attention, due to their unique physicochemical properties, that render them promising candidates for various applications in medicine and industry. This article offers a comprehensive overview of the most recent advancements in the manufacturing, characterization, and biomedical utilization of metal NPs, with a primary focus on silver and gold NPs. Their potential as effective anticancer, anti-inflammatory, and antimicrobial agents, drug delivery systems, and imaging agents in the diagnosis and treatment of a variety of disorders is reviewed. Moreover, their translation to therapeutic settings, and the issue of their inclusion in clinical trials, are assessed in light of over 30 clinical investigations that concentrate on administering either silver or gold NPs in conditions ranging from nosocomial infections to different types of cancers. This paper aims not only to examine the biocompatibility of nanomaterials but also to emphasize potential challenges that may limit their safe integration into healthcare practices. More than 100 nanomedicines are currently on the market, which justifies ongoing study into the use of nanomaterials in medicine. Overall, the present review aims to highlight the potential of silver and gold NPs as innovative and effective therapeutics in the field of biomedicine, citing some of their most relevant current applications.

Metabolomics-directed nanotechnology in viral diseases management: COVID-19 a case study

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is currently regarded as the twenty-first century's plague accounting for coronavirus disease 2019 (COVID-19). Besides its reported symptoms affecting the respiratory tract, it was found to alter several metabolic pathways inside the body. Nanoparticles proved to combat viral infections including COVID-19 to demonstrate great success in developing vaccines based on mRNA technology. However, various types of nanoparticles can affect the host metabolome. Considering the increasing proportion of nano-based vaccines, this review compiles and analyses how COVID-19 and nanoparticles affect lipids, amino acids, and carbohydrates metabolism. A search was conducted on PubMed, ScienceDirect, Web of Science for available information on the interrelationship between metabolomics and immunity in the context of SARS-CoV-2 infection and the effect of nanoparticles on metabolite levels. It was clear that SARS-CoV-2 disrupted several pathways to ensure a sufficient supply of its building blocks to facilitate its replication. Such information can help in developing treatment strategies against viral infections and COVID-19 based on interventions that overcome these metabolic changes. Furthermore, it showed that even drug-free nanoparticles can exert an influence on biological systems as evidenced by metabolomics.

Nano-Enabled Antivirals for Overcoming Antibody Escaped Mutations Based SARS-CoV-2 Waves

This review discusses receptor-binding domain (RBD) mutations related to the emergence of various SARS-CoV-2 variants, which have been highlighted as a major cause of repetitive clinical waves of COVID-19. Our perusal of the literature reveals that most variants were able to escape neutralizing antibodies developed after immunization or natural exposure, pointing to the need for a sustainable technological solution to overcome this crisis. This review, therefore, focuses on nanotechnology and the development of antiviral nanomaterials with physical antagonistic features of viral replication checkpoints as such a solution. Our detailed discussion of SARS-CoV-2 replication and pathogenesis highlights four distinct checkpoints, the S protein (ACE2 receptor coupling), the RBD motif (ACE2 receptor coupling), ACE2 coupling, and the S protein cleavage site, as targets for the development of nano-enabled solutions that, for example, prevent viral attachment and fusion with the host cell by either blocking viral RBD/spike proteins or cellular ACE2 receptors. As proof of this concept, we highlight applications of several nanomaterials, such as metal and metal oxide nanoparticles, carbon-based nanoparticles, carbon nanotubes, fullerene, carbon dots, quantum dots, polymeric nanoparticles, lipid-based, polymer-based, lipid-polymer hybrid-based, surface-modified nanoparticles that have already been employed to control viral infections. These nanoparticles were developed to inhibit receptor-mediated host-virus attachments and cell fusion, the uncoating of the virus, viral gene expression, protein synthesis, the assembly of progeny viral particles, and the release of the virion. Moreover, nanomaterials have been used as antiviral drug carriers and vaccines, and nano-enabled sensors have already been shown to enable fast, sensitive, and label-free real-time diagnosis of viral infections. Nano-biosensors could, therefore, also be useful in the remote testing and tracking of patients, while nanocarriers probed with target tissue could facilitate the targeted delivery of antiviral drugs to infected cells, tissues, organs, or systems while avoiding unwanted exposure of non-target tissues. Antiviral nanoparticles can also be applied to sanitizers, clothing, facemasks, and other personal protective equipment to minimize horizontal spread. We believe that the nanotechnology-enabled solutions described in this review will enable us to control repeated SAR-CoV-2 waves caused by antibody escape mutations.

Broad-Spectrum, Potent, and Durable Ceria Nanoparticles Inactivate RNA Virus Infectivity by Targeting Virion Surfaces and Disrupting Virus-Receptor Interactions

There is intense interest in developing long-lasting, potent, and broad-spectrum antiviral disinfectants. Ceria nanoparticles (CNPs) can undergo surface redox reactions (Ce³⁺ ↔ Ce⁴⁺) to generate ROS without requiring an external driving force. Here, we tested the mechanism behind our prior finding of potent inactivation of enveloped and non-enveloped RNA viruses by silver-modified CNPs, AgCNP1 and AgCNP2. Treatment of human respiratory viruses, coronavirus OC43 and parainfluenza virus type 5 (PIV5) with AgCNP1 and 2, respectively, prevented virus interactions with host cell receptors and resulted in virion aggregation. Rhinovirus 14 (RV14) mutants were selected to be resistant to inactivation by AgCNP2. Sequence analysis of the resistant virus genomes predicted two amino acid changes in surface-located residues D91V and F177L within capsid protein VP1. Consistent with the regenerative properties of CNPs, surface-applied AgCNP1 and 2 inactivated a wide range of structurally diverse viruses, including enveloped (OC43, SARS-CoV-2, and PIV5) and non-enveloped RNA viruses (RV14 and feline calicivirus; FCV). Remarkably, a single application of AgCNP1 and 2 potently inactivated up to four sequential rounds of virus challenge. Our results show broad-spectrum and long-lasting anti-viral activity of AgCNP nanoparticles, due to targeting of viral surface proteins to disrupt interactions with cellular receptors.

Antiviral activity of silver nanoparticles against the influenza A virus

Viral infections occupy an essential place in modern medicine, particularly a large group of diseases caused by the influenza viruses. They are rapidly transmitted and mutate quickly, which can lead to significant socio-economic consequences. Silver nanoparticles (AgNPs) are considered to be an effective antimicrobial agent. This study shows that they have strong antiviral properties against the influenza A virus infection. Their absence of cytotoxicity at inhibitory concentrations demonstrates that they could be an effective antiviral agent against this virus. As AgNPs inhibit the influenza A virus replication and spread, they could also be successfully used as a post-infection virostatic agent.

Antiviral Peptides Delivered by Chitosan-Based Nanoparticles to Neutralize SARS-CoV-2 and HCoV-OC43

The COVID-19 pandemic has made it clear that there is a crucial need for the design and development of antiviral agents that can efficiently reduce the fatality rate caused by infectious diseases. The fact that coronavirus mainly enters through the nasal epithelial cells and spreads through the nasal passage makes the nasal delivery of antiviral agents a promising strategy not only to reduce viral infection but also its transmission. Peptides are emerging as powerful candidates for antiviral treatments, showing not only a strong antiviral activity, but also improved safety, efficacy, and higher specificity against viral pathogens. Based on our previous experience on the use of chitosan-based nanoparticles to deliver peptides intra-nasally the current study aimed to explore the delivery of two-novel antiviral peptides making use of nanoparticles consisting of HA/CS and DS/CS. The antiviral peptides were chemically synthesized, and the optimal conditions for encapsulating them were selected through a combination of physical entrapment and chemical conjugation using HA/CS and DS/CS nanocomplexes. Finally, we evaluated the in vitro neutralization capacity against SARS-CoV-2 and HCoV-OC43 for potential use as prophylaxis or therapy.

Smart Nanomaterials in Cancer Theranostics: Challenges and Opportunities

Cancer is ranked as the second leading cause of death globally. Traditional cancer therapies including chemotherapy are flawed, with off-target and on-target toxicities on the normal cells, requiring newer strategies to improve cell selective targeting. The application of nanomaterial has been extensively studied and explored as chemical biology tools in cancer theranostics. It shows greater applications toward stability, biocompatibility, and increased cell permeability, resulting in precise targeting, and mitigating the shortcomings of traditional cancer therapies. The nanoplatform offers an exciting opportunity to gain targeting strategies and multifunctionality. The advent of nanotechnology, in particular the development of smart nanomaterials, has transformed cancer diagnosis and treatment. The large surface area of nanoparticles is enough to encapsulate many molecules and the ability to functionalize with various biosubstrates such as DNA, RNA, aptamers, and antibodies, which helps in theranostic action. Comparatively, biologically derived nanomaterials perceive advantages over the nanomaterials produced by conventional methods in terms of economy, ease of production, and reduced toxicity. The present review summarizes various techniques in cancer theranostics and emphasizes the applications of smart nanomaterials (such as organic nanoparticles (NPs), inorganic NPs, and carbon-based NPs). We also critically discussed the advantages and challenges impeding their translation in cancer treatment and diagnostic applications. This review concludes that the use of smart nanomaterials could significantly improve cancer theranostics and will facilitate new dimensions for tumor detection and therapy.

Viricidal Activity of Thermoplastic Polyurethane Materials with Silver Nanoparticles

The use of diverse Ag-based nanoparticulated forms has shown promising results in controlling viral propagation. In this study, a commercial nanomaterial consisting of ceramic-coated silver nanoparticles (AgNPs) was incorporated into thermoplastic polyurethane (TPU) plates using an industrial protocol, and the surface composition, ion-release dynamics and viricidal properties were studied. The surface characterization by FESEM-EDX revealed that the molar composition of the ceramic material was 5.5 P:3.3 Mg:Al and facilitated the identification of the embedded AgNPs (54.4 ± 24.9 nm). As determined by ICPMS, the release rates from the AgNP-TPU into aqueous solvents were 4 ppm/h for Ag and Al, and 28.4 ppm/h for Mg ions. Regarding the biological assays, the AgNP-TPU material did not induce significant cytotoxicity in the cell lines employed. Its viricidal activity was characterized, based on ISO 21702:2019, using the Spring viraemia of carp virus (SVCV), and then tested against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The results demonstrated that AgNP-TPU materials exhibited significant (75%) and direct antiviral activity against SVCV virions in a time- and temperature-dependent manner. Similar inhibition levels were found against SARS-CoV-2. These findings show the potential of AgNP-TPU-based materials as a supporting strategy to control viral spread.

Cellular uptake of metal oxide-based nanocomposites and targeting of chikungunya virus replication protein nsP3

Emergence of new pathogenic viruses along with adaptive potential of RNA viruses has become a major public health concern. Therefore, it is increasingly crucial to investigate and assess the antiviral potential of nanocomposites, which is constantly advancing area of medical biology. In this study, two types of nanocomposites: Ag/NiO and Ag₂O/NiO/ZnO with varying molar ratios of silver and silver oxide, respectively have been synthesised and characterised. Three metal/metal oxide (Ag/NiO) composites having different amounts of Ag nanoparticles (NPs) anchored on NiO octahedrons are AN-5 % (5 % Ag), AN-10 % (10 % Ag) and AN-15 % (15 % Ag)) and three ternary metal oxide nanocomposites (Ag₂O/NiO/ZnO) i.e., A/N/Z-1, A/N/Z-2, and A/N/Z-3 with different molar ratios of silver oxide (10 %, 20 % and 30 %, respectively) were evaluated for their antiviral potential. Cellular uptake of nanocomposites was confirmed by ICP-MS. Intriguingly, molecular docking of metal oxides in the active site of nsP3 validated the binding of nanocomposites to chikungunya virus replication protein nsP3. In vitro antiviral potential of nanocomposites was tested by performing plaque reduction assay, cytopathic effect (CPE) analysis and qRT-PCR. The nanocomposites showed significant reduction in virus titre. Half-maximal inhibitory concentration (IC₅₀) for A/N/Z-3 and AN-5 % were determined to be 2.828 and 3.277 µg/mL, respectively. CPE observation and qRT-PCR results were consistent with the data obtained from plaque reduction assay for A/N/Z-3 and AN-5 %. These results have opened new avenues for development of nanocomposites based antiviral therapies.

Copper-based nanoparticles against microbial infections

Drug-resistant bacteria and highly infectious viruses are among the major global threats affecting the human health. There is an immediate need for novel strategies to tackle this challenge. Copper-based nanoparticles (CBNPs) have exhibited a broad antimicrobial capacity and are receiving increasing attention in this context. In this review, we describe the functionalization of CBNPs, elucidate their antibacterial and antiviral activity as well as applications, and briefly review their toxicity, biodistribution, and persistence. The limitations of the current study and potential solutions are also shortly discussed. The review will guide the rational design of functional nanomaterials for antimicrobial application. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease.

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 synthesis and antimicrobial mechanism of nanoparticles: applications in agricultural and agrifood safety

The growing demand for food and its safety are a challenge for agriculture and agrifood. This has led to the incorporation of alternatives such as organic agriculture, the use of biocontrollers, the development of transgenic plants resistant to pathogens and the incorporation of nanotechnology. In this sense, agrochemicals based on nanoparticles (NPs) have been developed. Recently, the green synthesis of NPs has grown rapidly and, for this reason, molecules, microorganisms, fungi and plants are used. Synthesis from plant extracts offers a broad spectrum and, despite the fact that NPs are usually dispersed in size and shape, extensive antimicrobial effectiveness has been demonstrated at nanomolar concentrations. It has been shown that the mechanism of action can be through the dissipation of the driving force of the protons, the alteration of cellular permeability, the formation of bonds with the thiol group of the proteins, the generation of reactive species of oxygen, and the hyperoxidation of DNA, RNA and even the cell membrane. To improve the efficiency of NPs, modifications have been made such as coating with other metals, the addition of antibiotics, detergents and surfactants, as well as the acidification of the solution. Consequently, NPs are considered as a promising method for achieving safety in the agricultural and agrifood area. However, it is necessary to investigate the side effects of NPs, when applied in agroecological systems, on the textural, nutriment and sensory properties of food, as well as the impact on human health. © 2022 Society of Chemical Industry.

Recent advances in the use of inorganic nanomaterials as anti caries agents

Caries is the most prevalent and widespread chronic oral disease. Traditional caries filling materials, due to their lack of anti-caries capabilities, can readily develop secondary caries. Nanomaterials proposed as an effective approach for caries treatment can inhibit biofilm formation. It also can not only reduce demineralization but also promote remineralization. In recent years, nanotechnology in anti-caries materials, particularly nano-adhesive and nano-composite resin, has advanced rapidly. Because inorganic nanoparticles (NPs) interfere with bacterial metabolism and inhibit biofilm development, inorganic NPs have emerged as a new trend in dental applications. Metal and metal oxide NPs by releasing metal ions, oxidative stress induction, and non-oxidative mechanisms showed significant antimicrobial activity. For applying metal and metal oxide NPs as anti caries agents, silver, zinc, titanium, copper, and calcium ions have been shown significant attention. Moreover, fluoride functionalized inorganic NPs were also employed to improve their efficacy of them. The fluoride-functionalized NPs can promote remineralization, and inhibit demineralization by enhancing apatite formation. In this review, we have provided an overview and recent advances in the use of inorganic NPs as anti caries agents. Furthermore, their antimicrobial, remineralizing, and mechanical impacts on dental materials were discussed.

New insights from nanotechnology in SARS-CoV-2 detection, treatment strategy, and prevention

The recent outbreak of SARS-CoV-2 resulted into the deadly COVID-19 pandemic, which has made a profound impact on mankind and the world health care system. SARS-CoV-2 is mainly transmitted within the population via symptomatic carriers, enters the host cell via ACE2 and TMPSSR2 receptors and damages the organs. The standard diagnostic tests and treatment methods implemented lack required efficiency to beat SARS-CoV-2 in the race of its spreading. The most prominently used diagnostic test,reverse transcription-polymerase chain reaction (a nucleic acid-based method), has limitations including a prolonged time taken to reveal results, limited sensitivity, a high rate of false negative results, and lacking specificity due to a homology with other viruses. Furthermore, as part of the treatment, antiviral drugs such as remdesivir, favipiravir, lopinavir/ritonavir, chloroquine, daclatasvir, atazanavir, and many more have been tested clinically to check their potency for the treatment of SARS-CoV-2 but none of these antiviral drugs are the definitive cure or suitable prophylaxis. Thus, it is always required to combat SARS-CoV-2 spread and infection for a better and precise prognosis. This review answers the above mentioned challenges by employing nanomedicine for the development of improved detection, treatment, and prevention strategies for SARS-CoV-2. In this review, nanotechnology-based detection methods such as colorimetric assays, photothermal biosensors, molecularly imprinted nanoparticles sensors, electrochemical nanoimmunosensors, aptamer-based biosensors have been discussed. Furthermore, nanotechnology-based treatment strategies involving polymeric nanoparticles, metallic nanoparticles, lipid nanoparticles, and nanocarrier-based antiviral siRNA delivery have been depicted. Moreover, SARS-CoV-2 prevention strategies, which include the nanotechnology for upgrading personal protective equipment, facemasks, ocular protection gears, and nanopolymer-based disinfectants, have been also reviewed. This review will provide a one-site informative platform for researchers to explore the crucial role of nanomedicine in managing the COVID-19 curse more effectively.

Silver Nanoparticles: Review of Antiviral Properties, Mechanism of Action and Applications

New antiviral drugs and new preventive antiviral strategies are a target of intense scientific interest. Thanks to their peculiar properties, nanomaterials play an important role in this field, and, in particular, among metallic materials, silver nanoparticles were demonstrated to be effective against a wide range of viruses, in addition to having a strong antibacterial effect. Although the mechanism of antiviral action is not completely clarified, silver nanoparticles can directly act on viruses, and on their first steps of interaction with the host cell, depending on several factors, such as size, shape, functionalization and concentration. This review provides an overview of the antiviral properties of silver nanoparticles, along with their demonstrated mechanisms of action and factors mainly influencing their properties. In addition, the fields of potential application are analyzed, demonstrating the versatility of silver nanoparticles, which can be involved in several devices and applications, including biomedical applications, considering both human and animal health, environmental applications, such as air filtration and water treatment, and for food and textile industry purposes. For each application, the study level of the device is indicated, if it is either a laboratory study or a commercial product.

Advances in Antiviral Delivery Systems and Chitosan-Based Polymeric and Nanoparticulate Antivirals and Antiviral Carriers

Current antiviral therapy research is focused on developing dosage forms that enable highly effective drug delivery, providing a selective effect in the organism, lower risk of adverse effects, a lower dose of active pharmaceutical ingredients, and minimal toxicity. In this article, antiviral drugs and the mechanisms of their action are summarized at the beginning as a prerequisite background to develop relevant drug delivery/carrier systems for them, classified and briefly discussed subsequently. Many of the recent studies aim at different types of synthetic, semisynthetic, and natural polymers serving as a favorable matrix for the antiviral drug carrier. Besides a wider view of different antiviral delivery systems, this review focuses on advances in antiviral drug delivery systems based on chitosan (CS) and derivatized CS carriers. CS and its derivatives are evaluated concerning methods of their preparation, their basic characteristics and properties, approaches to the incorporation of an antiviral drug in the CS polymer as well as CS nanoparticulate systems, and their recent biomedical applications in the context of actual antiviral therapy. The degree of development (i.e., research study, in vitro/ex vivo/in vivo preclinical testing), as well as benefits and limitations of CS polymer and CS nanoparticulate drug delivery systems, are reported for particular viral diseases and corresponding antivirotics.

Functional Textile Materials for Blocking COVID-19 Transmission

The outbreak of COVID-19 provided a warning sign for society worldwide: that is, we urgently need to explore effective strategies for combating unpredictable viral pandemics. Protective textiles such as surgery masks have played an important role in the mitigation of the COVID-19 pandemic, while revealing serious challenges in terms of supply, cross-infection risk, and environmental pollution. In this context, textiles with an antivirus functionality have attracted increasing attention, and many innovative proposals with exciting commercial possibilities have been reported over the past three years. In this review, we illustrate the progress of textile filtration for pandemics and summarize the recent development of antiviral textiles for personal protective purposes by cataloging them into three classes: metal-based, carbon-based, and polymer-based materials. We focused on the preparation routes of emerging antiviral textiles, providing a forward-looking perspective on their opportunities and challenges, to evaluate their efficacy, scale up their manufacturing processes, and expand their high-volume applications. Based on this review, we conclude that ideal antiviral textiles are characterized by a high filtration efficiency, reliable antiviral effect, long storage life, and recyclability. The expected manufacturing processes should be economically feasible, scalable, and quickly responsive.

Probing the affinity of noble metal nanoparticles to the segments of the SARS-CoV-2 spike protein

Currently, scientists have devoted great efforts to finding effective treatments to combat COVID-19 infections. Although noble metal nanoparticles are able to realize protein modifications, their interactions with the protein are still unclear from the atomic perspective. To supply a general understanding, in this work, we have carried out theoretical calculations to investigate the interaction between protein segments (RBD1, RBD2, RBD3) of SARS-Cov-2 spike protein and a series of noble metal (Au, Ag, Cu, Pd, Pt) surfaces regarding the binding strength, protein orientations, and electronic modulations. In particular, the Au surface has shown the strongest binding preferences for the protein segments, which induces electron transfer between the Au and receptor-binding domain (RBD) segments. This further leads to the polarization of segments for virus denaturation. This work has offered a direct visualization of protein interactions with noble metal surfaces from the atomic level, which will benefit anti-virus material developments in the future.

Nano drug-delivery systems for management of AIDS: liposomes, dendrimers, gold and silver nanoparticles

AIDS causes increasing mortality every year. With advancements in nanomedicine, different nanomaterials (NMs) have been applied to treat AIDS and overcome its limitations. Among different NMs, nanoparticles (NPs) can act as nanocarriers due to their enhanced solubility, sustained release, targeting abilities and facilitation of drug-dose reductions. This review discusses recent advancements in therapeutics for AIDS/HIV using various NMs, mainly focused on three classifications: polymeric, liposomal and inorganic NMs. Polymeric dendrimers, polyethylenimine-NPs, poly(lactic-co-glycolic acid)-NPs, chitosan and the use of liposomal-based delivery systems and inorganic NPs, including gold and silver NPs, are explored. Recent advances, current challenges and future perspectives on the use of these NMs for better management of HIV/AIDS are also discussed.

Ostwald Ripening and Antibacterial Activity of Silver Nanoparticles Capped by Anti-Inflammatory Ligands

Silver nanoparticles (AgNPs) have been extensively studied during recent decades as antimicrobial agents. However, their stability and antibacterial activity over time have yet to be sufficiently studied. In this work, AgNPs were coated with different stabilizers (naproxen and diclofenac and 5-chlorosalicylic acid) in different concentrations. The suspensions of nanostructures were characterized by transmission electron microscopy, UV-Vis and FT-IR spectroscopic techniques. The antibacterial activity as a function of time was determined through microbiological studies against Staphylococcus aureus. The AgNPs show differences in stabilities when changing the coating agent and its concentration. This fact could be a consequence of the difference in the nature of the interaction between the stabilizer and the surface of the NPs, which were evaluated by FT-IR spectroscopy. In addition, an increase in the size of the nanoparticles was observed after 30 days, which could be related to an Ostwald maturation phenomenon. This result raises new questions about the role that stabilizers play on the surface of NPs, promoting size change in NPs. It is highly probable that the stabilizer functions as a growth controller of the NPs, thus determining an effect on their biological properties. Finally, the antibacterial activity was evaluated over time against the bacterium Staphylococcus aureus. The results showed that the protective or stabilizing agents can play an important role in the antibacterial capacity, the control of the size of the AgNPs and additionally in the stability over time.

Employing functionalized graphene quantum dots to combat coronavirus and enterovirus

The ongoing COVID-19 (i.e., coronavirus) pandemic continues to adversely affect the human life, economy, and the world's ecosystem. Although significant progress has been made in developing antiviral materials for the coronavirus, much more work is still needed. In this work, N-functionalized graphene quantum dots (GQDs) were designed and synthesized as the antiviral nanomaterial for Feline Coronavirus NTU156 (FCoV NTU156) and Enterovirus 71 (EV71)) with ultra-high inhibition (>99.9%). To prepare the GQD samples, a unique solid-phase microwave-assisted technique was developed and the cell toxicity was established on the H171 and H184 cell lines after 72 h incubation, indicating superior biocompatibility. The surface functionality of GQDs (i.e., the phenolic and amino groups) plays a vital role in interacting with the receptor-binding-domain of the spike protein. It was also found that the addition of polyethylene glycol is advantageous for the dispersion and the adsorption of functionalized GQDs onto the virus surface, leading to an enhanced virus inhibition. The functionality of as-prepared GQD nanomaterials was further confirmed where a functionalized GQD-coated glass was shown to be extremely effective in hindering the virus spread for a relatively long period (>20 h).

Colloidal Solutions as Advanced Coatings for Active Packaging Development: Focus on PLA Systems

Due to rising consumer demand the food packaging industry is turning increasingly to packaging materials that offer active functions. This is achieved by incorporating active compounds into the basic packaging materials. However, it is currently believed that adding active compounds as a coating over the base packaging material is more beneficial than adding them in bulk or in pouches, as this helps to maintain the physicochemical properties of the base material along with higher efficiency at the interface with the food. Colloidal systems have the potential to be used as active coatings, while the application of coatings in the form of colloidal dispersions allows for prolonged and controlled release of the active ingredient and uniform distribution, due to their colloidal/nano size and large surface area ratio. The objective of this review is to analyse some of the different colloidal solutions previously used in the literature as coatings for active food packaging and their advantages. The focus is on natural bio-based substances and packaging materials such as PLA, due to consumer awareness and environmental and regulatory issues. The antiviral concept through the surface is also discussed briefly, as it is an important strategy in the context of the current pandemic crisis and cross-infection prevention.

Antiviral role of nanomaterials: a material scientist's perspective

The present world continues to face unprecedented challenges caused by the COVID-19 pandemic. Collaboration between researchers of multiple disciplines is the need of the hour. There is a need to develop antiviral agents capable of inhibiting viruses and tailoring existing antiviral drugs for efficient delivery to prevent a surge in deaths caused by viruses globally. Biocompatible systems have been designed using nanotechnological principles which showed appreciable results against a wide range of viruses. Many nanoparticles can act as antiviral therapeutic agents if synthesized by the correct approach. Moreover, nanoparticles can act as carriers of antiviral drugs while overcoming their inherent drawbacks such as low solubility, poor bioavailability, uncontrolled release, and side effects. This review highlights the potential of nanomaterials in antiviral applications by discussing various studies and their results regarding antiviral potential of nanoparticles while also suggesting future directions to researchers.

Trends in Drug Delivery Systems for Natural Bioactive Molecules to Treat Health Disorders: The Importance of Nano-Liposomes

Drug delivery systems are believed to increase pharmaceutical efficacy and the therapeutic index by protecting and stabilizing bioactive molecules, such as protein and peptides, against body fluids' enzymes and/or unsuitable physicochemical conditions while preserving the surrounding healthy tissues from toxicity. Liposomes are biocompatible and biodegradable and do not cause immunogenicity following intravenous or topical administration. Still, their most important characteristic is the ability to load any drug or complex molecule uncommitted to its hydrophobic or hydrophilic character. Selecting lipid components, ratios and thermo-sensitivity is critical to achieve a suitable nano-liposomal formulation. Nano-liposomal surfaces can be tailored to interact successfully with target cells, avoiding undesirable associations with plasma proteins and enhancing their half-life in the bloodstream. Macropinocytosis-dynamin-independent, cell-membrane-cholesterol-dependent processes, clathrin, and caveolae-independent mechanisms are involved in liposome internalization and trafficking within target cells to deliver the loaded drugs to modulate cell function. A successful translation from animal studies to clinical trials is still an important challenge surrounding the approval of new nano-liposomal drugs that have been the focus of investigations. Precision medicine based on the design of functionalized nano-delivery systems bearing highly specific molecules to drive therapies is a promising strategy to treat degenerative diseases.

Therapeutic and diagnostic applications of nanoparticles in the management of COVID-19: a comprehensive overview

In December 2019, Coronavirus Disease 2019 (COVID-19) was reported in Wuhan, China. Comprehensive strategies for quick identification, prevention, control, and remedy of COVID-19 have been implemented until today. Advances in various nanoparticle-based technologies, including organic and inorganic nanoparticles, have created new perspectives in this field. These materials were extensively used to control COVID-19 because of their specific attribution to preparing antiviral face masks, various safety sensors, etc. In this review, the most current nanoparticle-based technologies, applications, and achievements against the coronavirus were summarized and highlighted. This paper also offers nanoparticle preventive, diagnostic, and treatment options to combat this pandemic.

Biomedical Applications of Biosynthesized Gold Nanoparticles from Cyanobacteria: an Overview

Recently there had been a great interest in biologically synthesized nanoparticles (NPs) as potential therapeutic agents. The shortcomings of conventional non-biological synthesis methods such as generation of toxic byproducts, energy consumptions, and involved cost have shifted the attention towards green syntheses of NPs. Among noble metal NPs, gold nanoparticles (AuNPs) are the most extensively used ones, owing to the unique physicochemical properties. AuNPs have potential therapeutic applications, as those are synthesized with biomolecules as reducing and stabilizing agent(s). The green method of AuNP synthesis is simple, eco-friendly, non-toxic, and cost-effective with the use of renewable energy sources. Among all taxa, cyanobacteria have attracted considerable attention as nano-biofactories, due to cellular uptake of heavy metals from the environment. The cellular bioactive pigments, enzymes, and polysaccharides acted as reducing and coating agents during the process of biosynthesis. However, cyanobacteria-mediated AuNPs have potential biomedical applications, namely, targeted drug delivery, cancer treatment, gene therapy, antimicrobial agent, biosensors, and imaging.

Supramolecular assembly of pentamidine and polymeric cyclodextrin bimetallic core-shell nanoarchitectures

Advanced nanoscale antimicrobials, originated from the combination of noble metal nanoparticles (NPs) with conventional antimicrobial drugs, are considered the next generation of antimicrobial agents. Therefore, there is an increasing demand for rapid, eco-friendly, and relatively inexpensive synthetic approaches for the preparation of nontoxic metallic nanostructures endowed with unique physicochemical properties. Recently, we have proposed a straightforward synthetic strategy that exploits the properties of polymeric β-cyclodextrin (PolyCD) to act as both the reducing and stabilizing agent to produce monodispersed and stable gold-based NPs either as monometallic (nanoG) structures or core-shell bimetallic (nanoGS) architectures with an external silver layer. Here, we describe the preparation of a supramolecular assembly between nanoGS and pentamidine, an antileishmanial drug endowed with a wide range of therapeutic properties (i.e., antimicrobial, anti-inflammatory, and anticancer). The physicochemical characterization of the supramolecular assembly (nanoGSP) in terms of size and colloidal stability was investigated by complementary spectroscopic techniques, such as UV-vis, ζ-potential, and dynamic light scattering (DLS). Furthermore, the role of PolyCD during the reduction/stabilization of metal NPs was investigated for the first time by NMR spectroscopy.

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.

Advanced Drug Delivery Platforms for the Treatment of Oral Pathogens

The oral cavity is a complex ecosystem accommodating various microorganisms (e.g., bacteria and fungi). Various factors, such as diet change and poor oral hygiene, can change the composition of oral microbiota, resulting in the dysbiosis of the oral micro-environment and the emergence of pathogenic microorganisms, and consequently, oral infectious diseases. Systemic administration is frequently used for drug delivery in the treatment of diseases and is associated with the problems, such as drug resistance and dysbiosis. To overcome these challenges, oral drug delivery systems (DDS) have received considerable attention. In this literature review, the related articles are identified, and their findings, in terms of current therapeutic challenges and the applications of DDSs, especially nanoscopic DDSs, for the treatment of oral infectious diseases are highlighted. DDSs are also discussed in terms of structures and therapeutic agents (e.g., antibiotics, antifungals, antiviral, and ions) that they deliver. In addition, strategies (e.g., theranostics, hydrogel, microparticle, strips/fibers, and pH-sensitive nanoparticles), which can improve the treatment outcome of these diseases, are highlighted.

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.

Role of Nanomaterials in COVID-19 Prevention, Diagnostics, Therapeutics, and Vaccine Development

Facing the deadly pandemic caused by the SARS-CoV-2 virus all over the globe, it is crucial to devote efforts to fighting and preventing this infectious virus. Nanomaterials have gained much attention after the approval of lipid nanoparticle-based COVID-19 vaccines by the United States Food and Drug Administration (USFDA). In light of increasing demands for utilizing nanomaterials in the management of COVID-19, this comprehensive review focuses on the role of nanomaterials in the prevention, diagnostics, therapeutics, and vaccine development of COVID-19. First, we highlight the variety of nanomaterials usage in the prevention of COVID-19. We discuss the advantages of nanomaterials as well as their uses in the production of diagnostic tools and treatment methods. Finally, we review the role of nanomaterials in COVID-19 vaccine development. This review offers direction for creating products based on nanomaterials to combat COVID-19.

A comprehensive review and outlook on the experimental techniques to investigate the complex dynamics of pulsed laser ablation in liquid for nanoparticle synthesis

Pulsed laser ablation in liquid (PLAL) has been established as one of the most efficient and impactful methods for producing pure and ligand-free nanoparticles (NPs). PLAL has successfully been utilized for the synthesis of metal NPs, semiconductor NPs, ceramic NPs, and even nanocomposites. A variety of NPs, including core-shell, nanocubes, nanorods, and many other complex structures, can be synthesized using PLAL. The versatility associated with PLAL has led to the synthesis of NPs that have found applications in the field of biomedicine, sensing technology, energy harvesting, and various industries. Despite all the aforementioned advantages, there has been an ambiguity in terms of conditions/parameters for the nanoparticle synthesis as reported by various research groups. This has led to a perception that PLAL provides little or no control over the properties of the synthesized NPs. The properties of the NPs are reliant on transient dynamics caused due to a high-intensity laser's interaction with the target material. To understand the process of nanoparticle synthesis and to control the properties of NPs, it is critical to understand the various processes that occur during PLAL. The investigation of PLAL is essential for understanding the dynamical processes involved. However, the investigation techniques employed to probe PLAL present their own set of difficulties, as high temporal as well as spatial resolution is a prerequisite to probe PLAL. Hence, the purpose of this Review is to understand the dynamical processes of PLAL and gain an insight into the various investigation techniques and their data interpretation. In addition to the current challenges, some ways of overcoming these challenges are also presented. The benefits of concurrent investigations with special emphasis on the simultaneous investigation by multiple techniques are summarized, and furthermore, a few examples are also provided to help the readers understand how the simultaneous investigation works.

Nanocomposites Based on Cerium, Lanthanum, and Titanium Oxides Doped with Silver for Biomedical Application

Nanosized composites CeO2–Ag, La2O3–Ag, and TiO2–Ag are a class of nanomaterials suitable for photocatalysis, optical devices, and photoelectrochemical elements. Further, nanocomposites with several wt.% of silver can be used as creating materials for pathogenic virus inactivation with pandemic-neutralizing potential. Thus, CeO2–Ag, La2O3–Ag, and TiO2–Ag nanocomposites are prospective materials due to their optical and biological activity. In the present work, CeO2–Ag, La2O3–Ag, and TiO2–Ag nanocomposites were synthesized by the co-precipitation method. The morphological and optical properties and the structure of the prepared nanocomposites were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM) with EDX, and nitrogen adsorption-desorption based on BET, Raman spectroscopy, and photoluminescence (PL). Both oxide matrixes corresponded to the cubic crystal lattice with the inclusion of argentum into the crystal lattice of oxides at relative low c(Ag) and reduction of silver on particle surface at 5 wt.% Ag and greater. The CeO2, TiO2, and La2O3 with a concentration of 4 wt.% Ag inhibited the growth processes of prokaryotic cells of E. coli, Bacillus sp., and S. aureus compared to pure oxides. Influenza A virus and herpes completely suppressed reproduction by nanocomposites of CeO2–Ag (2, 5 wt.%) and La2O3–Ag (2, 5 wt.%) action.

The Pivotal Role of Quantum Dots-Based Biomarkers Integrated with Ultra-Sensitive Probes for Multiplex Detection of Human Viral Infections

The spread of viral diseases has caused global concern in recent years. Detecting viral infections has become challenging in medical research due to their high infectivity and mutation. A rapid and accurate detection method in biomedical and healthcare segments is essential for the effective treatment of pathogenic viruses and early detection of these viruses. Biosensors are used worldwide to detect viral infections associated with the molecular detection of biomarkers. Thus, detecting viruses based on quantum dots biomarkers is inexpensive and has great potential. To detect the ultrasensitive biomarkers of viral infections, QDs appear to be a promising option as biological probes, while physiological components have been used directly to detect multiple biomarkers simultaneously. The simultaneous measurement of numerous clinical parameters of the same sample volume is possible through multiplex detection of human viral infections, which reduces the time and cost required to record any data point. The purpose of this paper is to review recent studies on the effectiveness of the quantum dot as a detection tool for human pandemic viruses. In this review study, different types of quantum dots and their valuable properties in the structure of biomarkers were investigated. Finally, a vision for recent advances in quantum dot-based biomarkers was presented, whereby they can be integrated into super-sensitive probes for the multiplex detection of human viral infections.

A novel inactivated virus system (InViS) for a fast and inexpensive assessment of viral disintegration

The COVID-19 pandemic has caused considerable interest worldwide in antiviral surfaces, and there has been a dramatic increase in the research and development of innovative material systems to reduce virus transmission in the past few years. The International Organization for Standardization (ISO) norms 18,184 and 21,702 are two standard methods to characterize the antiviral properties of porous and non-porous surfaces. However, during the last years of the pandemic, a need for faster and inexpensive characterization of antiviral material was identified. Therefore, a complementary method based on an Inactivated Virus System (InViS) was developed to facilitate the early-stage development of antiviral technologies and quality surveillance of the production of antiviral materials safely and efficiently. The InViS is loaded with a self-quenched fluorescent dye that produces a measurable increase in fluorescence when the viral envelope disintegrates. In the present work, the sensitivity of InViS to viral disintegration by known antiviral agents is demonstrated and its potential to characterize novel materials and surfaces is explored. Finally, the InViS is used to determine the fate of viral particles within facemasks layers, rendering it an interesting tool to support the development of antiviral surface systems for technical and medical applications.

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.

Advances in Nanomaterial-Based Platforms to Combat COVID-19: Diagnostics, Preventions, Therapeutics, and Vaccine Developments

The COVID-19 pandemic caused by the SARS-CoV-2, a ribonucleic acid (RNA) virus that emerged less than two years ago but has caused nearly 6.1 million deaths to date. Recently developed variants of the SARS-CoV-2 virus have been shown to be more potent and expanded at a faster rate. Until now, there is no specific and effective treatment for SARS-CoV-2 in terms of reliable and sustainable recovery. Precaution, prevention, and vaccinations are the only ways to keep the pandemic situation under control. Medical and scientific professionals are now focusing on the repurposing of previous technology and trying to develop more fruitful methodologies to detect the presence of viruses, treat the patients, precautionary items, and vaccine developments. Nanomedicine or nanobased platforms can play a crucial role in these fronts. Researchers are working on many effective approaches by nanosized particles to combat SARS-CoV-2. The role of a nanobased platform to combat SARS-CoV-2 is extremely diverse (i.e., mark to personal protective suit, rapid diagnostic tool to targeted treatment, and vaccine developments). Although there are many theoretical possibilities of a nanobased platform to combat SARS-CoV-2, until now there is an inadequate number of research targeting SARS-CoV-2 to explore such scenarios. This unique mini-review aims to compile and elaborate on the recent advances of nanobased approaches from prevention, diagnostics, treatment to vaccine developments against SARS-CoV-2, and associated challenges.

Silver nanoclusters show advantages in macrophage tracing in vivo and modulation of anti-tumor immuno-microenvironment

Macrophage-based nanomedicine represents an emerging powerful strategy for cancer therapy. Unfortunately, some obstacles and challenges limit the translational applications of macrophage-mediated nanodrug delivery system. For instance, tracking and effective cell delivery for targeted tumor sites remain to be overcome, and controlling the states of macrophages is still rather difficult due to their plastic nature in response to external stimuli. To address these critical issues, here, we reported a novel type of silver nanoclusters (AgNCs) with excellent fluorescent intensity, especially long-lasting cell labeling stability after endocytosis by macrophages, indicating promising applications in tracking macrophage-based nanomedicine delivery. Our mechanistic investigations uncovered that these merits originate from the escape of AgNCs from lysosomal degradation within macrophages. In addition, the AgNCs would prime the M1-like polarization of macrophages (at least in part) through the toll-like receptor 4 signaling pathway. The engineered macrophages laden with AgNCs could be employed for lung metastasis breast cancer treatment, showing the effective targeting propensity to metastatic tumors, remarkable regulation of tumor immune microenvironment and inhibition of tumor growth. Collectively, AgNC-trained macrophages appear to be a promising strategy for tumor immune-microenvironment regulation, which might be generalized to a wider spectrum of cancer therapeutics.

Therapeutic significance of nano- and biosensor technology in combating SARS-CoV-2: a review

The diagnosis of novel coronavirus (COVID-19) has gained the spotlight of the world's scientific community since December 2019 and it remains an important issue due to the emergence of novel variants around the globe. Early diagnosis of coronavirus is captious to prevent and hard to control. This pandemic can be eradicated by implementing suppressing strategies which can lead to better outcomes and more lives being saved. Therefore, the analysis showed that COVID-19 can only be managed by adopting public health measures, such as testing, isolation and social distancing. Much work has been done to diagnose coronavirus. Various testing technologies have been developed, opted and modified for rapid and accurate detection. The advanced molecular diagnosis relies on the detection of SARS-CoV-2 as it has been considered the main causative agent of this pandemic. Studies have shown that several molecular tests are considered essential for the confirmation of coronavirus infection. Various serology-based tests are also used in the detection and diagnosis of coronavirus including point-of-care assays and high-throughput enzyme immunoassays that aid in the diagnosis of COVID-19. Both these assays are time-consuming and have less diagnostic accuracy. Nanotechnology has the potential to develop new strategies to combat COVID-19 by developing diagnostics and therapeutics. In this review, we have focused on the nanotechnology-based detection techniques including nanoparticles and biosensors to obstruct the spread of SARS-CoV-2.

Methods for Green Synthesis of Metallic Nanoparticles Using Plant Extracts and their Biological Applications - A Review

Nanotechnology, a fast-developing branch of science, is gaining extensive popularity among researchers simply because of the multitude of applications it can offer. In recent years, biological synthesis has been widely used instead of physical and chemical synthesis methods, which often produce toxic products. These synthesis methods are now being commonly adapted to discover new applications of nanoparticles synthesized using plant extracts. In this review, we elucidate the various ways by which nanoparticles can be biologically synthesized. We further discuss the applications of these nanoparticles.

Partial carbonization of quercetin boosts the antiviral activity against H1N1 influenza A virus

Inflenza A viruses (IAVs) are highly transmissible and pathogenic Orthomyxoviruses, which have led to worldwide outbreaks and seasonal pandemics of acute respiratory diseases, causing serious threats to public health. Currently used anti-influenza drugs may cause neurological side effects, and they are increasingly less effective against mutant strains. To help prevent the spread of IAVs, in this work, we have developed quercetin-derived carbonized nanogels (CNGs_Qur) that display potent viral inhibitory, antioxidative, and anti-inflammatory activities. The antiviral CNGs_Qur were synthesized by mild carbonization of quercetin (Qur), which successfully preserved their antioxidative and anti-inflammatory properties while also contributed enhanced properties, such as water solubility, viral binding, and biocompatibility. Antiviral assays of co-treatment, pre-treatment, and post-treatment indicate that CNGs_Qur interacts with the virion, revealing that the major antiviral mechanism resulting in the inhibition of the virus is by their attachment on the cell surface. Among them, the selectivity index (SI) of CNGs_Qur270 (>857.1) clearly indicated its great potential for clinical application in IAVs inhibition, which was much higher than that of pristine quercetin (63.7) and other clinical drugs (4-81). Compared with quercetin at the same dose, the combined effects of viral inhibition, antioxidative and anti-inflammatory activities impart the superior therapeutic effects of CNGs_Qur270 aerosol inhalation in the treatment of IAVs infection, as evidenced by a mouse model. These CNGs_Qur effectively prevent the spread of IAVs and suppress virus-induced inflammation while also exhibiting good in vivo biocompatibility. CNGs_Qur shows much promise as a clinical therapeutic agent against infection by IVAs.