Aligned Nanofibers Research Articles

Promoting neurite outgrowth and neural stem cell migration using aligned nanofibers decorated with protrusions and galectin-1 coating.

Biomaterials integrated with both topological cues and biological modifications are urgently needed in regenerative medicine. Here, aligned nanofibrous scaffolds decorated with nanoscale SiO2 protrusions and galectin-1 coating are reported. Prospects in neurite outgrowth and neural stem cell migration are discussed for suitable use in neural tissue engineering.

Combining a Density Gradient of Biomacromolecular Nanoparticles with Biological Effectors in an Electrospun Fiber-Based Nerve Guidance Conduit to Promote Peripheral Nerve Repair.

Peripheral nerve injury is a serious medical problem with limited surgical and clinical treatment options. It is of great significance to integrate multiple guidance cues in one platform of nerve guidance conduits (NGCs) to promote axonal elongation and functional recovery. Here, a multi-functional NGC is constructed to promote nerve regeneration by combining ordered topological structure, density gradient of biomacromolecular nanoparticles, and controlled delivery of biological effectors to provide the topographical, haptotactic, and biological cues, respectively. On the surface of aligned polycaprolactone nanofibers, a density gradient of bioactive nanoparticles capable of delivering recombinant human acidic fibroblast growth factor is deposited. On the graded scaffold, the proliferation of Schwann cells is promoted, and the directional extension of neurites from both PC12 cells and dorsal root ganglions is improved in the direction of increasing particle density. After being implanted in vivo for 6 and 12 weeks to repair a 10-mm rat sciatic nerve defect, the NGC promotes axonal elongation and remyelination, achieving the regeneration of the nerve not only in anatomical structure but also in functional recovery. Taken together, the NGC provides a favorable microenvironment for peripheral nerve regeneration and holds great promise for realizing nerve repair with an efficacy close to autograft.

Charge-Boosting Strategy for Wearable Nanogenerators Enabled by Integrated Piezoelectric/Conductive Nanofibers.

The surface charge density enhancement by incorporating conductive paths into organic/inorganic piezoelectric composites is considered to be an effective way to achieve high-performance piezoelectric nanogenerators (PENGs). However, it is challenging to boost the charge density of aligned piezoelectric nanofibers due to the difficulty in efficiently building well-distributed conductive paths in their dense structure. In this work, a charge boosting strategy was proposed for enhancing the surface charge density of aligned piezoelectric nanofibers, that is, synchronously preparing piezoelectric/conductive hybrid nanofibers to realize the effective conductive paths for transferring the underlying charges to the surface of the PDMS/BaTiO3 composites. To this end, antimony-doped tin oxide (ATO) conductive nanofibers and barium titanate (BaTiO3) piezoelectric nanofibers with the same preparation conditions were selected and synchronously prepared by the polymer template electrospinning technology, followed by the calcination process. Benefiting from the well-distributed conductive paths for transferring the charges, the open-circuit voltage and short-circuit current of a PENG with 12 wt% ATO in hybrid nanofibers reached 46 V and 14.5 μA (30 kPa pressure), respectively, which were much higher than the pristine BaTiO3-based PENG. The high piezoelectric performance of the developed PENGs guaranteed their great potential applications in powering wearable microelectronics and monitoring human activity. This charge boosting strategy via the piezoelectric/conductive hybrid nanofibers may inspire the further development of high-performance energy harvesting technology.

A Nanofiber‐embedded Microfluidic Platform for Studying Neurobiology

AbstractDue to their biomimetic properties, electrospun nanofibers have been widely used in neurobiology studies. However, mechanistic understanding of cell‐nanofiber interactions is challenging based on the current in vitro culture systems due to the lack of control of spatiotemporal patterning of cells and difficulty in monitoring single cell behavior. To overcome these issues, we apply microfluidic technology in combination with electrospun nanofibers for in vitro studies of interactions between neurons and nanofiber materials. We demonstrate a unique nanofiber embedded microfluidic device which contains patterned aligned or random electrospun nanofibers as a new culture system. With this device, we test how different topographies affect axonal growth. Also, we conduct laser based axotomy on neurons cultured on our device to investigate axonal regeneration. The proposed device could be a useful tool for investigating nerve injury mechanisms and high‐throughput screening of biomaterials or drugs for nerve repair. The knowledge obtained using this device can be applicable to design medical devices such as nerve conduits for effective nerve regeneration.

Dual-Aligned carbon nanofiber scaffolds as heat conduction path to enhance thermal conductivity of polymer composites

To improve the thermal conductivity of thermal interface materials (TIM), we constructed a dual-aligned scaffold, i.e., both aligned carbon nanofiber (CNFs) in the microscopic structures and directional microporous channels, serving as the heat conduction paths of TIMs. The dual-aligned scaffold was firstly fabricated by combining magnetic alignment and conventional freeze-casting, and the composites of the dual-aligned scaffold and silicone rubber (D-AS/SR) were then obtained by immersing the dual-aligned scaffold into the silicone rubber with vacuum assistance. Through this method, not only the high axial thermal conductivity of CNFs can be fully utilized, but also a long-range continuous and parallel structure can be fabricated as the heat conduction paths of TIMs. The results show that the thermal conductivity of the D-AS/SR composites reached 4.66 W/(m·K) at 7.73 vol% CNFs, which is 1.5 times higher than that of the composites constructed by conventional freezing casting and 25 times higher than that of pure silicone rubber. Additionally, the compressive strength of the D-AS/SR composites was greatly improved, whereas the electrical insulation of the composites was significantly reduced, which limited the use of D-AS/SR composites in conditions requiring good electrical insulation.

Electrospun aligned nanofibers: A review

Electrospinning (e-spinning) is famous for the construction and production of ultrafine and continuous micro-/nanofibers. Then, the alignment of electrospun (e-spun) nanofibers becomes one of the most valuable research topics. Because aligned fibers have more advantages over random fibers, such as better mechanical properties, faster charge transport, more regular spatial structure, etc. This review summarizes various electrospinning techniques of fabricating aligned e-spun nanofibers, such as early conventional methods, near-field e-spinning, and three-dimensional (3D) printing e-spinning. Among them, four auxiliary preparation methods (e.g., auxiliary solid template, auxiliary liquid, auxiliary electromagnetic field and auxiliary airflow), two collection modes (static and dynamic collection), and the controllability of near-field e-spinning and 3D printing e-spinning are highlighted. The representative applications depending on aligned nanofibers are classified and briefly introduced, emphasizing in the fields of 1D applications (e.g., field-effect transistor, nanochannel and guidance carrier), 2D applications (e.g., platform for gas detection, filter, and electrode materials storage), and 3D applications (e.g., bioengineering, supercapacitor, and nanogenerator). At last, the challenges and prospects are addressed.

Sutureless transplantation of in vivo priming human mesenchymal stem cell sheet promotes the therapeutic potential for cardiac repair

The heart, contrary to its small size, vigorously pumps oxygen and nutrients to our entire body indeterminably; and thus, its dysfunction could be devastating. Until now, there ave been several major obstacles to applying a cardiac patch for the treatment for myocardial infarction, including poor integration and low engraftment rates, due to the highly-curved surface of the heart and its dynamic nature. Here, we demonstrate a novel way for a comprehensive cardiac repair achieved by the sutureless transplantation of a highly integrable in vivo priming bone marrow mesenchymal stem cell (BMSC) sheet based on the utilization of a highly aligned thermoresponsive nanofiber membrane. Moreover, we developed a BMSC sheet specialized for vascular regeneration through ‘in-vivo priming’ using human umbilical vein endothelial cells. A prolonged secretion of multiple angiogenic cytokines, such as vascular endothelial growth factor, angiopoietin-1, insulin-like growth factor-1, which was observed in vitro from the specialized BMSC sheet seemed to lead a significant improvement in the cardiac function, including intrinsic contractibility and remodeling. In this study, we provide strong evidence that in vivo priming of a human BMSC sheet develops the therapeutic potential for cardiac repair.

Enhance Fracture Toughness and Fatigue Resistance of Hydrogels by Reversible Alignment of Nanofibers.

Biological tissues, such as heart valve, tendon, etc., possess excellent mechanical properties, which arises from their inherent anisotropic arrangement of soft and hard phases. Inspired by the anisotropic structures, many methods have been developed to synthesize hydrogels that can achieve mechanical properties comparable to biological tissues. Here, we describe a new method to enhance fracture toughness and fatigue resistance of hydrogels by introducing nanofibers which can reversibly align with elastic deformation to form an anisotropic structure. As a demonstration, we introduce stiff, rod-like cellulose nanocrystals (CNCs) into a polyacrylamide (PAAm) network. CNCs aggregate into clusters to form hard phases and entangle with the PAAm network. The CNC/PAAm composite hydrogel is initially isotropic, becomes anisotropic upon loading, and recovers to be isotropic upon unloading. During the deformation, the aligned CNC clusters at the crack tip can transmit the stress over the size of the cluster, effectively resisting crack growth. We use photoelasticity and small-angle X-ray scattering (SAXS) tests to observe the change of microstructures associated with deformation. The fracture toughness of CNC/PAAm hydrogels with different sizes of CNCs can reach 1000 J/m2. The fatigue threshold is about 100 J/m2, an order of magnitude higher than that of PAAm hydrogel. This work provides a simple and general method to strengthen hydrogels under both monotonic and cyclic loads.

Enhanced performance of microbial fuel cells with a bacteria/shape-controllable aligned carbon nanofibers hybrid biofilm

Improving the bacterial loading contents and extracellular electron transfer (EET) efficiency are promising strategies to enhance the overall performance of microbial fuel cells (MFCs). Herein, an aligned carbon nanofiber-bacteria (ACNF-bacteria) hybrid is prepared and used as an efficient anode employing the electrospinning and co-filtration method. The ACNF matrix reveals rich porous structure, large specific surface area, and obviously improved electrocatalytic performance compared to the pristine carbon cloth (CC) anode. Specifically, MFC with the ACNF-bacteria anode achieves a maximum power density of 704 mW m−2, which is 1.7, 2.1 times higher than that of ACNF, CNF and CC anode. Impressively, the coulombic efficiency and chemical oxygen demand (COD) removal rate for ACNF-bacteria anode reach 47.4% and 87.9%, respectively, far exceeding the CC anode (29.3% and 47.6%). Considering all the factors of low cost, facial fabrication, and high-power output, this novel ACNF-bacteria anode provides great potential for high-performance and cost-effective MFCs in a large scale.

Fiber alignment and mode-mixity effects on fracture behavior of CNF/epoxy nanocomposite adhesive joints

In this study, the effect of carbon nanofiber (CNF) alignment was investigated on the enhancement of mixed mode fracture toughness of CNF/epoxy nanocomposite adhesive joints. CNFs were aligned in through-thickness direction inside epoxy using AC electric field. Asymmetric double cantilever beam (ADCB), Double cantilever beam (DCB), and end notched flexure (ENF) specimens were fabricated with pure epoxy, random, and aligned CNF/epoxy to investigate the mixed mode, mode-I, mode-II fracture response, respectively. Mixed mode and mode-II fracture toughness of 0.8 wt% aligned CNF/epoxy increased by 20% and 31.5%, respectively, compared to neat epoxy specimens (Gm,c = 960 ± 100 J/m2, GIIC = 2772 ± 116 J/m2). The mode-I fracture toughness of 0.8 wt% aligned CNF/epoxy was also increased by 195%, compared to the neat epoxy specimens (GIC = 300 ± 31 J/m2). Scanning electron micrograph analysis of fracture surfaces revealed that CNF pull-out, debonding and plastic void growth of epoxy are the key toughening mechanisms for all modes of fracture. These mechanisms were not so prevalent in the case of mixed mode and mode II fracture. Numerical modeling of all joints conducted using cohesive zone modeling matched satisfactorily with experimental findings.

Polyvinylidene fluoride/ barium titanate nanocomposite aligned hollow electrospun fibers as an actuator

Piezoelectric polymers such as polyvinylidene fluoride (PVDF) are widely utilized in electronic devices. However, their applications as high-performance flexible actuators are still not described well. The performance of the PVDF-based actuators is strongly related to the quality of the β-phase crystals. The elaboration of a one-dimensional element through electrospinning of aligned hollow nanofibers facilitates the formation of the β-phase crystals in PVDF and improves its actuation performance. Also, barium titanate (BaTiO3) nanoparticles can enhance the piezoelectric performance of the polymer actuators. The synergistic effect of the mechanical drawing and a high-intensity electric field during the electrospinning process resulted in the fabrication of ultra-thin-shell PVDF/BaTiO3 aligned hollow nanofibers with the predominant β-phase content of 99%, as was revealed by FTIR and XRD data. The aligned hollow nanofibers were then used as piezoelectric actuators with a high actuation deflection of 28 µm in response to the reasonable voltage of 480 V.

Effect of hydrogen flow rate on the synthesis of carbon nanofiber using microwave-assisted chemical vapour deposition with ferrocene as a catalyst

Carbon nanostructure materials are becoming of considerable commercial importance, with interest growing rapidly over the decade since the discovery of carbon nanofibers. In this study, a new novel method is introduced to synthesize the carbon nanofibers by gas-phase, where a single-stage microwave-assisted chemical vapour deposition approach is used with ferrocene as a catalyst and acetylene and hydrogen as precursor gases. Hydrogen flow rate plays a significant role in the formation of carbon nanofibers, as being the carrier and reactant gas in the floating catalyst method. The effect of process parameters such as microwave power, radiation time and gas ratio of C2H2/H2 was investigated statistically. The carbon nanofibers were characterized using scanning and transmission electron microscopy and thermogravimetric analysis. The analysis revealed that the optimized conditions for carbon nanofibers production were microwave power (1000 W), radiation time (35 min) and acetylene/hydrogen ratio (0.8). The field emission scanning electron microscope and transmission electron microscope analyses revealed that the vertical alignment of carbon nanofibers has tens of microns long with a uniform diameter ranging from 115 to 131 nm. High purity of 93% and a high yield of 12 g of CNFs were obtained. These outcomes indicate that identifying the optimal values for process parameters is important for synthesizing high quality and high CNF yield.

Development of high resilience spiral wound suture-embedded gelatin/PCL/heparin nanofiber membrane scaffolds for tendon tissue engineering

This study develops a spiral wound scaffold based on gelatin/PCL/heparin (GPH) nanofiber membranes for tendon tissue engineering. By embedding sutures in dual layers of aligned GPH nanofiber membranes, prepared from mixed electrospinning of gelatin and PCL/heparin solutions, we fabricate a high resilience scaffold intended for the high loading environment experienced by tendons. The basic fibroblast growth factor (bFGF) was anchored to GPH scaffold through bioaffinity between heparin and bFGF, aim to provide biological cues for maintenance of tenogenic phenotype. In addition, the aligned nanofiber morphology is expected to provide physical cues toward seeded tenocytes. With sustained release of bFGF, GPH-bFGF can enhance proliferation, up-regulate tenogenic gene expression, and increase synthesis of tendon-specific proteins by tenocytes in vitro. Furthermore, by properly maintaining tendon phenotypes, GPH-bFGF/tenocytes constructs showed improved mechanical properties over GPH-bFGF. From in vivo study using GPH-bFGF/tenocytes constructs to repair rabbit Achilles tendon defects, neotendon tissue formation was confirmed from histological staining and biomechanical analysis. These findings collectively demonstrate that the newly designed GPH-bFGF scaffold could provide a niche for inducing tendon tissue regeneration by effectively restoring the tendon tissue structure and function.

Rational design of stretchable and highly aligned organic/inorganic hybrid nanofiber films for multidirectional strain sensors and solar-driven thermoelectrics

Electrospinning technology is an effective and simple approach to prepare nanofiber films, which has been widely used in the wearable electronics based on energy harvesting. However, their application in the field of thermoelectrics is rarely reported mainly due to the ultralow performance and difficulty in maintaining temperature difference. Herein, we have designed highly aligned organic/inorganic hybrid nanofiber films with excellent stretchability and thermoelectric performance via electrospinning technology and surface coating methods. The aligned structure is beneficial to fast carrier transportation, in which a sevenfold increase in power factor is achieved as compared with the random structure. Additionally, novel radiative-cooling photothermal-heating electrodes are successfully designed to fabricate solar-driven thermoelectric generators based on the unique aligned nanofiber structure, providing a new concept to build in-plane temperature difference for ultrathin-film-based thermoelectrics. Furthermore, two highly aligned organic/inorganic hybrid nanofiber films are stacked orthogonally to assemble multidirectional strain sensors, which can distinguish the complex motion of human joints. These findings will inspire the future development and application of electrospun nanofiber-based thermoelectrics in the next-generation wearable electronics.

The alignment of the substrate nanofibers directing cellular energy metabolism

Electrospinning technology is critical in tissue engineering due to its ability to mimic the extracellular matrix. Cells sense their surroundings and perform a series of adaptive behaviors, including proliferation, differentiation, and migration. Here, we prepared two electrospinning fibers with different alignments to investigate the effect of the fibrous network on cell metabolism. We found that cells spread along the fiber orientation. Compared to random fibers, cells on aligned fibers were more elongated and expressed less phosphorylated myosin II. These morphological changes were associated with altered cellular metabolism. HK2, PDK1, and LDHA proteins expression and glycolytic capacity were enhanced in cells on random fibers. These results tentatively demonstrated the influence of substrate morphology on the metabolic state of cells.

3D cell/scaffold model based on aligned-electrospun-nanofiber film/hydrogel multilayers for construction of anisotropic engineered tissue.

Many tissues have a three-dimensional (3D) anisotropic structure compatible with their physiological functions. Engineering an in vitro 3D tissue having the natural structure and functions is a hotspot in tissue engineering with application for tissue regeneration, drug screening, and disease modeling. Despite various designs that have successfully guided the cellular alignment, only a few of them could precisely control the orientation of each layer in a multilayered construct or achieve adequate cell contact between layers. This study proposed a design of a multilayered 3D cell/scaffold model, that is, the cell-loaded aligned nanofiber film/hydrogel (ANF/Gel) model. The characterizations of the 3D cell-loaded ANF/Gel model in terms of design, construction, morphology, and cell behavior were systematically studied. The ANF was produced by efficiently aligned electrospinning using a self-designed, fast-and-easy collector, which was designed based on the parallel electrodes and modified with a larger gap area up to about 100 cm2. The nanofibers generated by this simple device presented numerous features like high orientation, uniformity in fiber diameter, and thinness. The ANF/Gel-based cell/scaffold model was formed by encapsulating cell-loaded multilayered poly(lactic-co-glycolic acid)-ANFs in hydrogel. Cells within the ANF/Gel model showed high viability and displayed aligned orientation and elongation in accordance with the nanofiber orientation in each film, forming a multilayered tissue having a layer spacing of 60 μm. This study provides a multilayered 3D cell/scaffold model for the in vitro construction of anisotropic engineered tissues, exhibiting potential applications in cardiac tissue engineering.

Electrospun aligned poly(ε-caprolactone) nanofiber yarns guiding 3D organization of tendon stem/progenitor cells in tenogenic differentiation and tendon repair.

Hierarchical anisotropy structure directing 3D cellular orientation plays a crucial role in designing tendon tissue engineering scaffolds. Despite recent development of fabrication technologies for controlling cellular organization and design of scaffolds that mimic the anisotropic structure of native tendon tissue, improvement of tenogenic differentiation remains challenging. Herein, we present 3D aligned poly (ε-caprolactone) nanofiber yarns (NFYs) of varying diameter, fabricated using a dry-wet electrospinning approach, that integrate with nano- and micro-scale structure to mimic the hierarchical structure of collagen fascicles and fibers in native tendon tissue. These aligned NFYs exhibited good in vitro biocompatibility, and their ability to induce 3D cellular alignment and elongation of tendon stem/progenitor cells was demonstrated. Significantly, the aligned NFYs with a diameter of 50 μm were able to promote the tenogenic differentiation of tendon stem/progenitor cells due to the integration of aligned nanofibrous structure and suitable yarn diameter. Rat tendon repair results further showed that bundled NFYs encouraged tendon repair in vivo by inducing neo-collagen organization and orientation. These data suggest that electrospun bundled NFYs formed by aligned nanofibers can mimic the aligned hierarchical structure of native tendon tissue, highlighting their potential as a biomimetic multi-scale scaffold for tendon tissue regeneration.

Shape-reconfigurable transparent wood based on solid-state plasticity of polythiourethane for smart building materials with tunable light guiding, energy saving, and fire alarm actuating functions

Transparent wood (TW) is a promising light and thermal management material that has enormous potential for energy-efficient engineering applications. However, almost all the polymers currently used to fabricate TW fall under the thermosetting or thermoplastic category, exhibiting extremely monotonous performance and lack of intelligence. Herein, a smart shape-reconfigurable TW is developed through infiltration the polythiourethane covalent adaptable networks (PTU CANs) into the delignified wood (DW) scaffolds. Benefiting from the solid-state plasticity and thermadapt shape-memory behavior of PTU CANs and the highly aligned cellulose nanofibers of the DW scaffolds, the resulting TW exhibits reconfigurable shape memory behavior, excellent optical properties (transmittance of ∼90% and tunable light guiding effects), and low thermal conductivity (212.8 mW m−1K−1). In addition, the tensile strength, modulus, and toughness of TW are 60.14 MPa, 2.09 GPa, and 1.19 MJ m−3, respectively. Moreover, the reconfigurable shape-memory performance of the TW allows it to be used as a smart actuator for designing a fire alarm system. Compared with traditional TW, the TW reported in this work not only maintains high optical transmittance, but also exhibits excellent reconfigurable shape memory properties, which can promote the high-value utilization for TW. The incorporation of the shape reconfiguration, light guiding, energy saving, and fire alarm actuating properties to the TW opens a new avenue for the design and development of advanced functional and intelligent building materials.

Membrane supported poly(butylene adipate-co-terephthalate) nanofibrous matrices as cardiac patch: Effect of basement membrane for the fiber deposition and cellular behavior

Electrospun nanofibrous matrices are convenient biomaterials that mimic extracellular matrices for adhesion, migration, proliferation, and differentiation of cells. The aim of this study is to optimize the electrospinning parameters for poly(butylene adipate-co-terephthalate) (PBAT) nanofiber production by the response surface methodology (RSM) and to develop a suitable material design for the usability of PBAT in cardiac tissue engineering. Therefore, electrospun PBAT nanofibrous matrices collected on solvent-casted polycaprolactone (PCL) or PBAT basement membranes at optimized conditions. The attachment and proliferation behavior of the H9C2 rat cardiomyoblasts investigated on different PBAT and PCL surface features as a model cell line. For this purpose, neat PBAT and PCL films have been used comparatively with both random (R-PBAT) and aligned PBAT (A-PBAT) nanofibers coated films. The effect of polymer concentration, flow rate, applied voltage, and needle tip-connector distance on fiber diameter and alignment was examined in the electrospinning process and optimum processing parameters were determined by RSM. The PBAT nanofibers were spun on basement membranes with 10% (w/v) polymer concentration, 1 mL/h volumetric flow rate, 2000 rpm collector rotation velocity (for aligned ones), 15 kV applied voltage, and 20 cm needle tip-collector distance. The average diameter of random (R-PBAT) and aligned (A-PBAT) nanofibers was calculated as 555 ± 126 nm and 417 ± 137 nm. The mechanical test results showed that the alignment topography increased the elastic modulus of PBAT nanofibers compared to random matrices. The alignment of fibers found as 91% and 75% within the ± 10° range for A-PBAT/SC-PBAT and A-PBAT/SC-PCL, respectively. These findings showed that usage of PCL, instead of PBAT, as basement membrane decrease the alignment of deposited nanofibers. A 7-day cell culture study conducted with H9C2 cells seeded samples to investigate the influence of these differences on cell behavior. The results indicated that the alignment of fibers provides a suitable topography to proliferate and spread in myocyte morphology for H9C2 cells especially compared to neat films. Cellular behavior and nanofiber deposition have been affected by the usage of various basement membrane polymers. These findings demonstrated that the usage of basement membrane as support material provides the required thickness and mechanical properties to the aligned PBAT nanofiber matrices, and this double layer structure might be a promising candidate for cardiac tissue engineering with further studies.

Self-powered biocompatible humidity sensor based on an electrospun anisotropic triboelectric nanogenerator for non-invasive diagnostic applications

The development of innovative devices that enables real-time monitoring of physiological activities and environmental conditions for healthcare applications has gained momentum in recent years. However, it is still a challenge to fabricate a self-sustainable wearable device with inherent comfort, long-time wearing and electrostatic discharge (EDS) safety for the monitoring of human-status. Herein, we developed a self-powered humidity sensor using an electrospun anisotropic triboelectric nanogenerator (A-TENG) composed of aligned MXene nanofibers (NFs) and cellulose acetate (CA) NFs. Importantly, such developed anisotropic structure of TENG exhibits its potential in sensitive moisture detection upon fast adsorption/desorption of water molecules due to increased pore length of prepared NFs. Moreover, it also benefits the device in reducing the EDS risks based on the working orientation of A-TENG. The practical application of detecting the skin moisture using finger-tapping is also demonstrated. Furthermore, CA NFs render superior antibacterial performance due to the high release of loaded copper nanoparticles at targeted skin surfaces, enabling long-time wearability of A-TENG. The above findings suggest that the highly ordered alignment of collected NFs is found to be favorable for the development of future-generation wearable devices.