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.

The use of toxic crosslinking agents and reagents in the fabrication of hydrogels is a frequent issue which is particularly concerning for biomedical or food packaging applications. In this study, novel antibacterial bionanocomposite films were obtained through a simple solvent casting technique without using any crosslinking substance. Films were made from a flexible and transparent whey protein matrix containing zinc oxide nanoparticles synthesised via a wet chemical precipitation route. The physicochemical and functional properties of the ZnO nanoparticles and of the composite films were characterised, and their antibacterial activity was tested against S. epidermidis and E. coli. The synthesised ZnO nanoparticles had an average size of about 30 nm and a specific surface area of 49.5 m²/g. The swelling ratio of the bionanocomposite films increased at basic pH, which is an appealing feature in relation to the absorption of chronic wound exudate. A n-ZnO concentration-dependent antibacterial effect was observed for composite films. In particular, marked antibacterial activity was observed against S. epidermidis. Overall, these findings suggest that this novel material can be a promising and sustainable alternative in the design of advanced solutions for wound dressing or food packaging.

Space resources activities are currently the objective of a thriving cross-disciplinary global effort aimed at assessing their role and potential in the future of humankind. New innovative mission concepts, legal frameworks, and advanced technologies are being actively developed and proposed with the final goal of enabling profitable and efficient space resource utilization. The immediate location for these impacts is the Moon. In sight of this bright cohort of imminent perspectives, it is imperative for the global community to properly assess the potential effects and consequences of the forthcoming space resources activities, with the goal of including sustainability in the foundations of the ongoing progress and ensuring its enforcement in every future endeavor. Within this context, this article addresses the topics of Moon mining waste management and a lunar circular economy as key issues in the sustainable utilization of space resources. The most promising technologies are considered for lunar resources extraction and processing—with special focus on water—correlating their waste generation potential to the scale of the efforts implemented and to the projected availability of the resources of interest. Importance is also given to the corollary activities of space mining—such as logistics and transport operations—for their implications in waste management. Protocols and technologies with the lower waste generation potential are identified and further scenarios are elaborated for waste handling, reduction, reuse, and recycle, as well as end-of-life strategies for mining plants. This report's recommendations are proposed for the development of incremental regulation for waste management, including but not limited to the definition of common areas of noninterest for waste disposal and regulatory obligations for conducting impact assessments before the establishment of mining activities. Please note that this abstract is submitted under the auspices of the Space Generation Advisory Council, as part of the activities of the Space Exploration Project Group.