Protein-based materials for sustainable, multifunctional air filtration

Diverse air pollutants pose a significant threat to human health, making the development of multifunctional air filtration necessary. To mitigate the risk of secondary pollution associated with conventional materials, there has been a growing focus on biomaterials. Compared with other bio-polymer air filters, natural proteins include a huge amount of various functional groups (e.g. amino acids) enabling multiple filtration capabilities. In recent years, abundant natural proteins as raw materials, such as zein (corn protein), soy protein, gelatin silk, etc., for constructing multifunctional air filters were reported, and many important results caused attentions. Thus, a comprehensive overview of the progress and achievements of protein-based air filters is necessary. In this review, the advantages of protein materials, filtration mechanisms, and structural designs for optimizing filtration performance, as well as other features such as moisture resistance and antimicrobial properties for protein-based air filters are comprehensively summarized and/or analyzed. Finally, future research perspectives and developments of multifunctional protein materials for air filtration are proposed.