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Electrospun nanofibrous membranes have garnered significant attention in antimicrobial applications, owing to their intricate three-dimensional network that confers an interconnected porous structure, high specific surface area, and tunable physicochemical properties, as well as their notable capacity for loading and sustained release of antimicrobial agents. Tailoring polymer or hybrid-based nanofibrous membranes with stimuli-responsive characteristics further enhances their versatility, enabling them to exhibit broad-spectrum or specific activity against diverse microorganisms. In this review, we elucidate the pivotal advancements achieved in the realm of stimuli-responsive antimicrobial electrospun nanofibers operating by light, temperature, pH, humidity, and electric field, among others. We provide a concise introduction to the strategies employed to design smart electrospun nanofibers with antimicrobial properties. The core section of our review spotlights recent progress in electrospun nanofiber-based systems triggered by single- and multi-stimuli. Within each stimulus category, we explore recent examples of nanofibers based on different polymers and antimicrobial agents. Finally, we delve into the constraints and future directions of stimuli-responsive nanofibrous materials, paving the way for their wider application spectrum and catalyzing progress toward industrial utilization. [ABSTRACT FROM AUTHOR]

A disposable electrochemical immunosensor for on‐site detection of aflatoxin B1(AFB1), one of the most toxic mycotoxins in agri‐food products, was fabricated through a low‐cost cut‐printing method and then modified with zein/polypyrrole(PPy) electrospun nanofibers onto which anti‐AFB1 monoclonal antibodies were immobilized covalently. Fabrication was possible with an innovative and simple approach to adsorb nanofibers onto the working electrode during electrospinning. Electrochemical impedance spectroscopy was employed as the principle of detection, and the data collected with a portable potentiostat were treated with information visualization techniques. The nanostructured immunosensor showed a high sensitivity for AFB1 with a linear detection range from 0.25 to 10 ng mL−1 and a theoretical limit of detection of 0.092 ng mL−1, which is adequate to detect AFB1 in food, according to regulatory agencies. [ABSTRACT FROM AUTHOR]

Oxygen-generating biomaterials have the potential to improve tissue engineering and regenerative therapeutic strategies. However, the development of such materials capable of controlling the local partial pressure of oxygen (pO2) in the long term is still a major challenge. Here we report nanostructured composite membranes comprising electrospun fibers exhibiting a bead-on-string structure as a controlled oxygen-release system for periodontitis treatment. For this, calcium peroxide nanoparticles (CaO2 NPs) and manganese dioxide nanosheets (MnO2 NSs) were incorporated into the structure of hydrophobic electrospun poly (lactic acid) (PLA)-based nanofibers. We use CaO2 NPs as hydrogen peroxide (H2O2)-generating precursors when exposed to water, while MnO2 NSs were applied as a nanozyme to catalyze the decomposition of H2O2 to the final oxygen product. Our results revealed that the beads on the fibrous structure acted as reservoirs of CaO2 NPs and MnO2 NSs. Moreover, the composite membranes provided sustained oxygen release over 7 days, where levels were modulated by the CaO2 NP content. Such constructs exhibited suitable physicochemical properties and antimicrobial activities against some bacteria (e.g., Porphyromonas gingivalis and Treponema denticola) typically associated with aggressive and chronic periodontitis. In vitro studies also revealed that the membranes were not cytotoxic toward human oral keratinocyte (Nok-si) cells as well as enhanced the cell viability when high content of CaO2 NP and MnO2 NS were incorporated into the fiber's structure. Taken together, our results demonstrate that the nanostructured composite membranes show potential to be employed as oxygen-release platforms for periodontal tissue regeneration. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) detection has gained considerable attention in agricultural and environmental monitoring, chemical and pharmaceutical processing, and disease diagnosis, which requires the development of sensors with high sensitivity. Herein, we propose a novel gas sensor based on nanocomposites of TiO2 hollow nanofibers and polyaniline (PANI) for the sensitive detection of ammonia at room temperature. TiO2 nanostructures in anatase phase were prepared by the combination of coaxial electrospinning and calcination treatment. The resulting material was mixed with PANI and deposited onto gold interdigitated electrodes (IDEs). The hybrid platforms exhibited superior sensing performance compared to the platform based on their individual phases, which is ascribed to a synergistic effect from p‐n heterojunction formation. Specifically, the platforms based on TiO2/PANI nanocomposite showed a fast response towards NH3 (e. g., 55 s at 10 ppm) at room temperature (25 °C). Additionally, the platform demonstrated the ability to detect NH3 at low concentrations (10–30 ppm) and a detection mechanism was proposed to explain the results. Overall, these results show the promise of electrospun TiO2 hollow nanofibers/PANI composites for the development of high‐performance room temperature ammonia sensors. [ABSTRACT FROM AUTHOR]

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