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The field of flame retardancy for polymeric materials (i.e. plastics, foams and in particular textiles) is currently facing several changes and challenges because some of the current halogenated or phosphorus-based flame retardants (FRs) have proven to be persistent, bioaccumulative, carcinogenic and/or toxic for animals and humans. Thus, the search for highly efficient green flame retardant products, which are exploitable by using simple and environmentally-friendly techniques (i.e. impregnation/exhaustion, layerby-layer), is driving the researchers towards the development of worthy alternatives. In this context, very recently, biomacromolecules (in particular proteins and deoxyribonucleic acid) have been thoroughly investigated because they exhibit significant potentials as novel green FRs for selected fabrics (cotton, polyester and their blends), as well as for bulk polymers (ethylene vinyl-acetate copolymers) and foamed polyurethane substrates. This work aims to review our recent results related to the "unconventional" use of these biomacromolecules as FRs with low-environmental impact for fabric substrates, as well as the challenges and the perspectives that these products may offer in the forthcoming years in the field of flame retardancy for textiles. To provide the basic knowledge necessary for understanding the role of biomacromolecules as FRs for textiles to the readers, first of all the description of the structure, main properties and conventional applications of proteins and deoxyribonucleic acid is provided; the thermal and thermo-oxidative stability, the reaction to a flame exposure or to an irradiative heat source of the selected fabricscotton, polyester and their blendswill be discussed, as well.

Chronic wounds are a major concern for global health, affecting millions of individuals worldwide. As their occurrence is correlated with age and age-related comorbidities, their incidence in the population is set to increase in the forthcoming years. This burden is further worsened by the rise of antimicrobial resistance (AMR), which causes wound infections that are increasingly hard to treat with current antibiotics. Antimicrobial bionanocomposites are an emerging class of materials that combine the biocompatibility and tissue-mimicking properties of biomacromolecules with the antimicrobial activity of metal or metal oxide nanoparticles. Among these nanostructured agents, zinc oxide (ZnO) is one of the most promising for its microbicidal effects and its anti-inflammatory properties, and as a source of essential zinc ions. This review analyses the most recent developments in the field of nano-ZnO–bionanocomposite (nZnO-BNC) materials—mainly in the form of films, but also hydrogel or electrospun bandages—from the different preparation techniques to their properties and antibacterial and wound-healing performances. The effect of nanostructured ZnO on the mechanical, water and gas barrier, swelling, optical, thermal, water affinity, and drug-release properties are examined and linked to the preparation methods. Antimicrobial assays over a wide range of bacterial strains are extensively surveyed, and wound-healing studies are finally considered to provide a comprehensive assessment framework. While early results are promising, a systematic and standardised testing procedure for the comparison of antibacterial properties is still lacking, partly because of a not-yet fully understood antimicrobial mechanism. This work, therefore, allowed, on one hand, the determination of the best strategies for the design, engineering, and application of n-ZnO-BNC, and, on the other hand, the identification of the current challenges and opportunities for future research.

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