Future filters- A new approach to face coverings

<p>In common with many universities, academics at the University of Lincoln formed groups to help in the struggle against the Covid pandemic. A syndicate drawn from the schools of design, engineering and pharmacy developed an effective virus trapping filter that does not compromise on permeability. The group acknowledged that for a rapid roll-out of results, concurrent engineering involving the whole supply chain from suppliers to producers is necessary, and so worked from the beginning in close association with their industrial partners. The face covering originated in the school of design with a product to protect children from urban particulates. For a face covering to have a significant effect on public health, it must have a high degree of take-up by a volunteer clientele, in this case the general public, so it must be comfortable and stylish. For the wearer, the ideal face covering should offer low resistance to breathing. For a face covering, low permeability is also desirable in that it allows freer passage of breath through the covering rather than around the edges. From a simple engineering view this is awkward: passive filter mechanisms rely on the physical entanglement of particulates. Particulates – the air born viruses must contact a mesh of fibres of sufficiently low porosity to prevent the further passage of the particulates through the filter. Clearly, improvements to efficiency by this method will result in a decrease in porosity and an increase in resistance to flow. Improvements of this type are likely to be of little benefit, if the face covering becomes uncomfortable, and therefore undesirable to wear.The group investigated methods to increase filter efficiency without a disagreeable decrease in filter permeability. The team identified a commonly used neutraceutical called fucoidan, a sulfated water-soluble polysaccharide extracted from brown seaweeds such as Ascopbyllum nodosum, Fucus vesiculosus, and Saccharina japonica, as glue to stick the viruses to the filter fibres. The potential of this material as a virus adherent was proposed by Kwon et al (2020a) and offered a way forward to improve filter efficiency without lowering permeability, because the need for physical entanglement with the filter matrix to occur if a virus particle is to be captured is much reduced. This improved filter concept uses molecular biology and chemical mimicry to attract and entrap the virus on the fibres. The biochemical treated fibre admixtures enhance the propensity for viral binding through developing a molecular-level synergy on the polymer substrate which exploits the COVID-19 spike to hACE2 receptor interaction. This method was perceived to have the advantage that however the virus mutates, it must still stick to a common surface, namely the internal mucosal surfaces of the human respiratory tract.</p>