Nanoparticles against Coronavirus-Myth or Reality?
Coronaviruses are a group of viruses that attack the upper and lower respiratory tracts in humans and cause a range of illnesses from the common cold to more serious forms such as severe acute respiratory syndrome (SARS) and the Middle East respiratory syndrome (MERS) which are life-threatening. Coronavirus are in the form of spheres with an average diameter of 125 nm. They have a viral envelope and a positive-sense single-stranded RNA genome. Virus particles of coronavirus have four types of structural proteins, namely spike (S), membrane (M), envelope (E), and nucleocapsid (N) proteins, among which the S protein has a crucial role in attaching the virus to its host’s cells and enabling it to enter the cells; thus, an effective way of fighting this virus could be targeting the S protein’s mechanism of action by developing special drugs and inhibiting compounds.
Given their high specific surface area and the possibility of being functionalized with a wide range of functional groups, nanomaterials such as gold nanoparticles and carbon quantum dots (CQDs) are standout choices for interacting with viruses and preventing their entry into cells.
In a recent paper titled “Functional Carbon Quantum Dots as Medical Countermeasures to Human Coronavirus”, a group of researchers explain the mechanism of action of these CQDs, revealed to be inhibition of HCoV-229E entry that could be due to interaction of the functional groups of the CQDs with HCoV-229E entry receptors; surprisingly, an equally large inhibition activity was observed at the viral replication step. After one viral life cycle – which is 5.5 hours for coronavirus – a great inhibition activity was also observed at the viral replication step. These CQDs with an average diameter of 10 nm and excellent solubility in water can be perfect candidates for winning the battle against coronavirus, because they easily enter the cell through endocytosis and interact with the virus’s protein, thereby preventing viral genome replication .
A Japanese group also demonstrated the possible effect of gold nanoparticles: Gold nanoparticle‐adjuvanted S protein induces a strong antigen‐specific IgG response against severe acute respiratory syndrome‐related coronavirus infection, but fails to induce protective antibodies and limit eosinophilic infiltration in lungs .
Another attempt was developed recently by chemical engineer Thomas Webster from Northeastern University in Boston, Massachusetts. He has proposed eradicating the coronavirus with nanoparticles. He said: “It’s not just having one approach to detect whether you have a virus and another is to use it as a therapy, but having the same particle the same approach, for both your detection and therapy. We have to identify what we need to put in our nanoparticle to attract it to that virus.”.
So, dear colleagues, now is your time to shine!
 Aleksandra Łoczechin, Karin Séron, Alexandre Barras, Emerson Giovanelli, Sandrine Belouzard, Yen-Ting Chen, Nils Metzler-Nolte, Rabah Boukherroub, Jean Dubuisson, Sabine Szunerits, Functional Carbon Quantum Dots as Medical Countermeasures to Human Coronavirus, ACS Appl. Mater. Interfaces 2019, 11, 46, 42964-42974.
 Hanako Sekimukai, Naoko Iwata‐Yoshikawa, Shuetsu Fukushi, Hideki Tani, Michiyo Kataoka, Tadaki Suzuki, Hideki Hasegawa, Kenichi Niikura, Katsuhiko Arai, Noriyo Nagata, Microbiology and Immunology, November 2019.
 SEBASTIAN KETTLEY, Coronavirus cure: Groundbreaking nanoparticles could wipe out COVID-19 infections – claim, published in Daily and Sunday Express, March 6, 2020.
 Layqah, L.A., Eissa, S. An electrochemical immunosensor for the corona virus associated with the Middle East respiratory syndrome using an array of gold nanoparticle-modified carbon electrodes. Microchim Acta 186, 224 (2019). https://doi.org/10.1007/s00604-019-3345-5