Mask material: challenges and virucidal properties as an effective solution against coronavirus SARS-CoV-2

Abstract COVID-19 viruses are primarily transmitted between people via respiratory droplets generated from an infected person while coughing, sneezing, exhaling or close contact. Hence, the use of masks are part of prevention and control measures to limit the spread of COVID-19. A comprehensive study on various materials used in masks is required. The filtration efficiency of cotton masks increases with increase in thread count and number of layers, but breathability is affected and therefore a risk for longer durations. Cotton-based masks have filtration efficiency ranging from 5% to 80% depending on the number of layers. Combinations of different hybrid fabric materials and design have an efficiency ranging from 37% to 97%. Bio-cellulose, which is derived from cellulosic biomass by synthesis techniques involving various physical and chemical processes followed by refining techniques, possesses remarkable properties including biodegradability, biocompatibility, low toxicity, etc., making it the most suitable mask material. Masks made of bio-cellulose have an important property of hydrophilicity which makes it adhere to the face tightly, giving a cooling effect to the face. Use of nanocellulose masks can help attaining filtration efficiency up to 99.9980–99.9995% along with other desirable properties. Hence, there is an immediate need to address the issues and challenges of mask materials and work towards the design and development of low cost masks to overcome these shortcomings by the researchers and manufacturers.