The research project, in which the CSIC and the University of Barcelona are also participating along with the UGR, aims to develop an aerosol with lipids similar to those of the skin that emulate its impermeability when applied to the mucous membranes—thus reducing or avoiding penetration by the virus
Aerosols could be used on the nasal and oral mucosae to provide additional protection to facemasks in the fight against Covid-19
Scientists from the University of Granada (UGR), in collaboration with the Spanish Higher National Research Council (CSIC) and the University of Barcelona (UB), are working on a project to strengthen the nasal and oral mucosae, increase their barrier effect, and reduce their permeability to limit or prevent penetration by SARS-CoV-2, the virus that causes COVID-19.
The SARS-CoV-2 Coronavirus infiltrates mainly through the nasal or oral mucosa, as opposed to the relatively low incidence of penetration through the skin. The study therefore aims to develop aerosols that ‘mimic’ skin lipids in their chemical and structural composition, as the latter are known to be more impervious to Coronavirus.
If this approach proves successful, better-reinforced lipid structures would form in the mucosae, which could help prevent the virus from penetrating. This innovation would not provide full protection, but the reduction in permeability could partially impede penetration of the virus at the systemic level and thus protect people. It could be particularly valuable for healthcare workers.
The research team comprises the Cosmetic and Textile Innovations Research Group of the Institute for Advanced Chemistry of Catalonia (IQAC), which pertains to the CSIC; the UB; and the UGR. Together, they are conducting the research & development project ‘Mucosal Modification as a Protection against SARS-COV-2”.
After optimizing the most suitable methodologies to evaluate the permeability of the mucosae, the researchers will first apply different aerosol formulations based on compounds similar to those of the skin on oral and nasal mucosae in an attempt to determine their impermeability. Next, they will analyse the capacity of a virus model (similar to coronavirus) to penetrate the mucosae that have been protected with the new aerosol.
“This innovation will probably not provide complete protection, but the decrease in permeability will partially prevent the virus from penetrating at the systemic level and will probably provide additional protection to that of facemasks,” explains Beatriz Clares Naveros, a lecturer at the UGR’s Department of Pharmacy and Pharmaceutical Technology, who is participating in this project together with Mª Luisa Coderch Negra (CSIC/IQAC) and Ana Cristina Calpena Campmany (UB). The team of scientists from the CSIC specialise in the chemical and structural composition of skin lipids. They have worked extensively on the extraction and characterization of lipids from keratin tissues such as the stratum corneum (the outermost layer) of skin, hair, wool, and so on.
Barrier function
Ana Calpena, from the UB’s Faculty of Pharmacy, will bring to the project her specialist knowledge of the structure, kinetics, and permeability of mucosae. Beatriz Clares will be in charge of designing and developing different formulations with protective and mucoadhesive action that can be applied to the mucosae to increase their barrier function properties.
As the outermost layer of the epidermis, the stratum corneum is made up of about 20 sub-layers of dead cells, known as corneocytes, which form a layered packing structure. Between the corneocytes are perfectly-structured lipid bilayers composed of lipids (ceramides, fatty acids, and cholesterol) that help create a practically impenetrable protective barrier. This layer becomes permeable only in the case of wounds, burns, or skin diseases.
However, the mucosae—the barriers that protect the mouth, pharynx, bronchi, lungs, and digestive system—are much more permeable and thus vulnerable to infection. “The mucous membranes are open to the outside world and that is why they have mechanisms against microbes, such as the enzymes in our saliva or the cilia in our bronchi, which are like minuscule hairs designed to filter the air we breathe. But these mechanisms are insufficient in the face of a virus like SARS-Cov-2,” the researchers explain.
“The potential impact would be huge if the entire population could be protected via the nasal mucosa from SARS-CoV-2, even partially. Today, the only protection against Covid-19 infection is based on the use of facemasks. We do not know the extent to which permeability could be reduced, but it would at least provide additional protection to the mask,” the authors note.
The raw materials used must preserve the natural properties of healthy mucosae and, at the same time, block the virus from entering, chemically and/or mechanically. The researchers will analyse the combined use of formulations that block or degrade the virus to provide synergistic effects. The design of these formulations will take into account two criteria, composition and dosage form, as both could be influential in fulfilling the aim of the project.
As well as their respective areas of specialisation, all the researchers involved in the project have extensive experience in topical administration and, between them, have carried out hundreds of absorption/permeation studies to evaluate the penetration of active ingredients through the skin or mucosae.
Cross-section of porcine buccal mucosa for ex vivo studies
The UGR researcher Beatriz Clares Naveros
Media enquiries:
Beatriz Clares Naveros, Department of Pharmacy and Pharmaceutical Technology
Faculty of Pharmacy, University of Granada
Tel.: + 34 958 246664
Email: beatrizclares@ugr.es
