The pandemic situation caused by coronavirus clearly demonstrated the need for alternatives able to protect the respiratory tract and inactivate the infectious agents. Based on this, antibacterial face-mask filters of polycaprolactone (PCL) dopped with magnesium oxide (MgO) and copper oxide (CuO) nanoparticles (NPs) were produced using an electrospinning technique. A morphological analysis of electrospun meshes evaluated the success of nanoparticles’ incorporation as well as the average fibers’ diameters (481 ± 272 nm). The performance of electrospun nanofibers was also assessed in terms of tensile strength (0.88 ± 0.25 MPa), water vapor permeability (11,178.66 ± 35.78 g·m⁻²·day⁻¹), stability under wet conditions and antibacterial activity according to the standard guidelines. The filters showed structural stability up to 2 h of washing and improved antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) for optimized concentrations of MgO and CuO NPs. Overall, electrospun meshes with antibacterial activity were successfully developed for advanced filtering applications.

Aqueous extracts of commercially available red macroalgae Porphyra dioica were integrated as inner coatings of food-grade polypropylene (PP) films through use of electrospinning and electrospraying technologies. Two coating formulations (A = 5 wt% P. dioica extract and 7.5 wt% polyvinyl alcohol (PVA); B = 1 wt% P. dioica extract, 1 wt% PVA, and 17% gelatine) were evaluated as to their capacity to delay spoilage of minced chicken breasts, through monitoring of microbial growth (total mesophile aerobic colony counts), colour stability, lipid oxidation (thiobarbituric acid reactive substances (TBARS)), and sensory analysis over a 4-day refrigerated storage. Scanning electron microscopy (SEM) imaging revealed an increased nanofiber and nanoparticle density on extract-enriched fibers, without compromise to their morphology or the homogeneity of the coatings. Total microbial counts on coating B samples was significantly (p < 0.001) reduced compared to uncoated plastic wraps. The coated samples also exhibited fewer colour degradation, though the coatings did not differ substantially from uncoated plastic wrap. Sensory analysis test subjects successfully distinguished the raw samples based on their treatment and gave a positive approval rating (66.7%) to the extract-enriched coatings when asked about edibility post storage.

The use of X-rays as a first-line treatment for gastric tumors is constrained by inaccurate target delineation and high toxicity to surrounding healthy tissues. The potential of inorganic nanoparticles (INPs; e.g. gold, silver, titanium oxide, tungsten oxide) in imaging and cancer therapy has been discussed as a solution to improve radiotherapy effectiveness, particularly in situations of challenging organ segmentation. X-rays interact with these INPs leading to the release of photons and electrons motivated by the photoelectric effect and Compton scattering that induces a cascade effect, resulting in the breakdown of DNA strands of tumor cells. Despite the associated radio-enhancing advantages, concerns have been raised regarding the bioaccumulation and potential toxicity of these nanoparticles, which could limit their administration and, consequently, their efficiency. To address these limitations, delivery systems based on novel biomaterials designs have been developed. These systems aim of achieve a more localized effect of NPs through targeting strategies, functionalization and use of delivery platforms that do not compromise surrounding healthy tissues. This review discusses the results of dose escalation induced by INPs in gastric tumors, along with the impact of design of INPs on the radiobiological effects observed. Furthermore, it explores prospective developments for combined therapy and potential alternatives for local delivery of nanoparticles. STATEMENT OF SIGNIFICANCE: Gastric cancer (GC) affects over more than one million globally each year. Considering the limited efficacy of chemo- and radiotherapies, surgical resection remains the standard treatment. However, stomach function and the patient quality of life are often compromised after surgical intervention. To enhance the effectiveness of radiotherapy in GC, small particles - typically composed of high atomic number materials - are being explored for their ability to increase tumor cell sensitivity to the X-rays. The delivery strategies and optimal design of these particles within the gastric environment are critical factors under investigation to maximize their radiosensitizing effects. The reduction of treatment invasiveness, and gastric cancer recurrence are key aspects associated with the translation of this approach to clinical routine.

The use of electrospun meshes has been proposed as highly efficient protective equipment to prevent respiratory infections. Those infections can result from the activity of micro-organisms and other small dust particles, such as those resulting from air pollution, that impair the respiratory tract, induce cellular damage and compromise breathing capacity. Therefore, electrospun meshes can contribute to promoting air-breathing quality and controlling the spread of such epidemic-disrupting agents due to their intrinsic characteristics, namely, low pore size, and high porosity and surface area. In this review, the mechanisms behind the pathogenesis of several stressors of the respiratory system are covered as well as the strategies adopted to inhibit their action. The main goal is to discuss the performance of antimicrobial electrospun nanofibers by comparing the results already reported in the literature. Further, the main aspects of the certification of filtering systems are highlighted, and the expected technology developments in the industry are also discussed.

The use of nanoparticles in electrospinning has gained great attention in recent years, due to nanoparticle characteristics, namely their high surface area to volume ratio