The role of nanotechnology in the fight against COVID-19

By Dr. Ramya Dwivedi, Ph.D.Mar 15 2021

Nanomedicine is a very powerful tool with the potential to mitigate the burden of disease by providing nanoparticle-based carriers and vaccines. A recent review by a team of interdisciplinary researchers looked at its role in the diagnostics, therapeutics, strategies and future perspectives for coronavirus disease 2019 (COVID-19).

Appearing in the journal Nanomedicine, the review summarized all the exciting advances made using diverse nanomaterials (polymeric, inorganic self-assembling materials and peptide-based) towards COVID-19 prevention, diagnosis and therapy.

Study: Nanotechnology against the novel coronavirus (severe acute respiratory syndrome coronavirus 2): diagnosis, treatment, therapy and future perspectives. Image Credit: Andrii Vodolazhskyi / Shutterstock

COVID-19 is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the novel coronavirus first identified in Wuhan, China, in December 2019. A positive-stranded RNA betacoronavirus, SARS-CoV-2 belongs to the largest group of viruses, the Nidovirales order, Cornidovirineae suborder and Coronaviridae family. The main characteristics of the virus include rapid mutation, altered tissue tropism, cross-species transmission and adaptation to various epidemiological conditions.

To date, the SARS-CoV-2 has infected over 118 million people worldwide and caused over 2.6 million deaths. Due to the virus’s high transmissibility and infectivity, extreme mitigation measures, such as the closure of offices, isolation, lockdown measures, and travel restrictions, were adopted worldwide. This brought ordinary activity in many sectors to a grinding halt, with devastating social and economic consequences.

While vaccines are being developed at an unprecedented pace – with some already approved and being rolled out – therapeutic advances that can mitigate severe disease in those the virus infects are still needed.

COVID-19 is a heterogeneous disease, causing multiple clinical manifestations – a huge challenge to the healthcare professionals in diagnosing the cause and treating the patients. Many approaches, strategies and technologies are required to understand the host-pathogen interaction and the disease, optimize best assays, and design effective drugs and therapy.

It is reported that, to date, nanotechnology-based tools have been effective in preclinical studies against a variety of pathogens, including respiratory viruses, herpes virus, human papillomavirus and HIV. In this context, nanotechnology draws immediate focus to aid with the COVID-19.

The nanotechnology-based strategies for COVID-19 disease management include the development of tools for rapid, accurate and sensitive diagnosis, the improvement of contact tracing tools, the production of effective disinfectants, the delivery of mRNA vaccines into human cells and the delivery of antiviral agents into the body.

Nanomaterials are less than one micrometer in size, falling in the nano-regime. This small size is comparable to the size of the virus itself, endowing nanomaterial with effective functional qualities in combating it. The small size also renders a high surface-to-volume ratio, enabling the nanomaterial to be excellent cargo-delivery moieties, improving targeted drug delivery and gene modifications and also enhancing interactions between analyte and sensor (allowing fast and accurate virus detection).

Such nanoparticle-based carriers address concerns such as cargo degradation, no bioavailability or rapid clearance of the delivery of drugs, genes and proteins to the patient’s body.

Metal nanoparticles such as silver, copper and titanium dioxide are alternatives currently used as chemical disinfectants. The unique physical and chemical properties of the particles in the nano-size range can be amply utilized in devising strategies against COVID-19.

Nanotechnology-based treatments for COVID-19 infections

The reviewers summarized the strategies for the development of novel nano-therapeutic materials for improving the efficacy of COVID-19 treatment. These included fabrication of polymeric nanoparticles with rapid and high mucus penetration features, the development of biodegradable, nontoxic and stable nanoparticles that could be used in the lung with minimum pulmonary toxicity during treatment, surface modification of nanoparticles by conjugation of PEG as a capping agent and targeting moieties to minimize adverse effects of therapy. The researchers have listed the active and effective antiviral nanostructured materials in the review.

Role of nanotechnology in vaccine development

A new generation of vaccines, called nanovaccines, has been developed, using nanoparticles to deliver antigens into the human body. It has been established that nanoparticles can target both adaptive (T cells, B cells) and innate (macrophages, monocytes and neutrophils) immune systems at the cellular level. The nanoparticles can deliver or act as an intrinsic adjuvant, with tunable physical loading of antigens.

The COVID-19 mRNA-based vaccines (made by BioNTech-Pfizer and Moderna) are encapsulated in positively charged lipid nanoparticles (LNPs), enabling resistance to RNase-mediated degradation, stable self-assembling particles that can be injected by various routes.

Other propitious vehicles for mRNA delivery are cationic polymer nanoparticles, polyethyleneimine, oil-in-water (O/W) cationic nanoemulsion and PEG-lipid functionalized dendrimer nanoparticles.

Nanomaterial applications in diagnosing COVID-19

Metallic nanoparticles are mostly intended for diagnostic purposes rather than therapy. Based on changes in surface plasmon resonance, selective naked-eye detection of COVID-19 is possible when the AuNPs (gold nanoparticles) capped with antisense oligonucleotides interact with RNA specimens within just 10 mins. This can diagnose and detect the number of positive COVID-19 cases without requiring any advanced instrumental facilities and equipment.

Future strategies by nanotechnology for COVID-19

In discussing the unsolved concerns, the reviewers pointed to the high-mutating RNA viruses that need a rapid solid approach to tackle. Overall, the profound role of nanotechnology and nanoscience is undeniable, but these promising materials could cause severe issues in lung and respiratory systems, the reviewers warned. Successful combination therapies that may involve nano-drug co-delivery systems, however, could be effective alternative options to combat the heterogeneous COVID-19.