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Electrospun nanofiber scaffolds have become vital in biomedical applications due to their high surface area and tunable properties. Chitosan (CS) is widely used, but its rapid degradation limits its effectiveness. This study addresses this limitation by blending CS with polycaprolactone (PCL) and applying genipin cross‐linking to enhance its stability and mechanical properties. Scanning electron microscopy indicated a uniform morphology of the electrospun fibers, and further, the crystallinity of the scaffolds before and after cross‐linking is verified. Fourier‐transform infrared spectroscopy is used to analyze the chemical structure, identifying the presence of trifluoroacetic acid residues in the as‐spun fibers. These residues are successfully eliminated through neutralization and cross‐linking, which are critical for enhancing stability and cell viability in in‐vitro studies. Mechanical testing revealed that cross‐linked CS+PCL scaffolds exhibit a 350% increase in tensile strength compared to pure CS, and zeta potential reaches the favorable for cell development ‐26.27 mV. The cytotoxicity assay results with murine NIH 3T3 fibroblast cells indicate the suitability of CS+PCL scaffolds for targeted tissue engineering and wound healing. This work establishes the potential for fine‐tuning scaffold properties to create stable, functional, and biocompatible substrates for extended biomedical use. [ABSTRACT FROM AUTHOR]

The global climate change is mainly caused by carbon dioxide (CO2) emissions. To help reduce CO2 emissions and conserve thermal energy, sustainable materials based on flexible thermal insulation are developed to minimize heat flux, drawing inspiration from natural systems such as polar bear hairs. The unique structure of hollow double‐shell fibers makes it possible to achieve low thermal conductivity in the material while retaining exceptional elasticity, allowing it to adapt to insulation systems of any shape. The layered system of porous mats reaches a thermal conductivity coefficient of 0.031 W∙m⁻¹∙K⁻¹ and enables to reduce the heat transfer. The results achieved using scanning thermal microscopy (SThM) correlate with the simulated heat flow in the case of individual fibers. This research study brings new insights into the energy efficiency of domestic environments, thereby addressing the growing demand for sustainable and high‐performance insulation materials for saving energy loss and reducing pollution footprint. [ABSTRACT FROM AUTHOR]

Given global water scarcity and the quest for sustainable energy, there's a pressing need for integrated approaches addressing water‐energy interdependence worldwide. A practical approach for this challenge involves the implementation of fog water collectors. Herein, a polyvinylidene fluoride (PVDF) multifunctional device capable of harvesting water and electricity from wind is developed and tested, collecting up to 365 mg cm−2 h−1 of fog water. Due to the piezoelectric nature of electrospun PVDF, these yarns and meshes not only serve as piezoelectric sensors, enabling the detection of incoming fog flow and determination of its speed and, bust also harvest electricity by charging a capacitor, making it a green and renewable power source. In this study, promising insights are offered into developing efficient fog water collection methods and utilizing piezoelectric fiber‐based yarns and meshes for multifunctional applications in sustainable water management, energy harvesting, and sensing in a single device. [ABSTRACT FROM AUTHOR]

Nanofibrous materials generated through electrospinning have gained significant attention in tissue regeneration, particularly in the domain of bone reconstruction. There is high interest in designing a material resembling bone tissue, and many scientists are trying to create materials applicable to bone tissue engineering with piezoelectricity similar to bone. One of the prospective candidates is highly piezoelectric poly(vinylidene fluoride) (PVDF), which was used for fibrous scaffold formation by electrospinning. In this study, we focused on the effect of PVDF molecular weight (180,000 g/mol and 530,000 g/mol) and process parameters, such as the rotational speed of the collector, applied voltage, and solution flow rate on the properties of the final scaffold. Fourier Transform Infrared Spectroscopy allows for determining the effect of molecular weight and processing parameters on the content of the electroactive phases. It can be concluded that the higher molecular weight of the PVDF and higher collector rotational speed increase nanofibers' diameter, electroactive phase content, and piezoelectric coefficient. Various electrospinning parameters showed changes in electroactive phase content with the maximum at the applied voltage of 22 kV and flow rate of 0.8 mL/h. Moreover, the cytocompatibility of the scaffolds was confirmed in the culture of human adipose-derived stromal cells with known potential for osteogenic differentiation. Based on the results obtained, it can be concluded that PVDF scaffolds may be taken into account as a tool in bone tissue engineering and are worth further investigation. [ABSTRACT FROM AUTHOR]

Skin allergies and diseases, including atopic dermatitis (AD), affect millions worldwide. Current treatments for AD are often expensive, leading to a need for cost‐effective solutions. Here, using fiber‐based patches to maintain and increase skin hydration is explored, which helps treat eczema and AD. Nanofiber membranes are manufactured via electrospinning of eight different polymers: nylon 6 (PA6), polyimide (PI), poly(3‐hydroxybuty‐rate‐co‐3‐hydroxyvalerate (PHBV), poly(l‐lactide) (PLLA), polycaprolactone (PCL), and polystyrene (PS), and two molecular weights poly(vinyl butyral‐co‐vinyl alcohol‐co‐vinyl acetate) (PVB). Further, their morphology is examined through scanning electron microscopy (SEM), fibers, and pores diameter, wettability, and membrane thickness. Additionally, water vapor transmission rates (WVTR) are measured, and notably, skin hydration tests are conducted before and after using evening primrose oil‐infused patches. The comparison and findings highlight the flexibility of electrospun patches, demonstrating their potential in maintaining skin hydration for 6 h and enhancing skin moisture, which are necessary in AD treatment. These insights, which focus on selecting the most effective performance patches, help improve skin moisture, leading to tailored treatments for AD, which can significantly impact the efforts to reduce healthcare costs and simplify skincare steps. [ABSTRACT FROM AUTHOR]

In vitro cytotoxicity assessment is indispensable in developing new biodegradable implant materials. Zn, which demonstrates an ideal corrosion rate between Mg‐ and Fe‐based alloys, has been reported to have excellent in vivo biocompatibility. Therefore, modifications aimed at improving Zn's mechanical properties should not degrade its biological response. As sufficient strength, ductility and corrosion behavior required of load‐bearing implants has been obtained in plastically deformed Zn‐3Ag‐0.5Mg, the effect of simultaneous Ag and Mg additions on in vitro cytocompatibility and antibacterial properties was studied, in relation to Zn and Zn‐3Ag. Direct cell culture on samples and indirect extract‐based tests showed almost no significant differences between the tested Zn‐based materials. The diluted extracts of Zn, Zn‐3Ag, and Zn‐3Ag‐0.5Mg showed no cytotoxicity toward MG‐63 cells at a concentration of ≤12.5%. The cytotoxic effect was observed only at high Zn2+ ion concentrations and when in direct contact with metallic samples. The highest LD50 (lethal dose killing 50% of cells) of 13.4 mg/L of Zn2+ ions were determined for the Zn‐3Ag‐0.5Mg. Similar antibacterial activity against Escherichia coli and Staphylococcus aureus was observed for Zn and Zn alloys, so the effect is attributed mainly to the released Zn2+ ions exhibiting bactericidal properties. Most importantly, our experiments indicated the limitations of water‐soluble tetrazolium salt‐based cytotoxicity assays for direct tests on Zn‐based materials. The discrepancies between the WST‐8 assay and SEM observations are attributed to the interference of Zn2+ ions with tetrazolium salt, therefore favoring its transformation into formazan, giving false cell viability quantitative results. [ABSTRACT FROM AUTHOR]