Electrospinning Technology Research Articles

STING Membrane Prevents Post-Surgery Tissue Adhesion and Tumor Recurrence of Colorectal Cancer.

Surgery is the standard treatment regimen for resectable colorectal cancer (CRC). However, it is very hard to completely remove all cancer cells in clinical practice, leading to the high recurrence rates of the disease. Moreover, the post-surgery tissue adhesion greatly prevents the possibility of reoperation, significantly limiting the long-term surviving of CRC patients. To overcome CRC recurrence and avoid the post-surgery tissue adhesion, this work develops a novel stimulator of interferon genes "STING" membrane based on the coaxial electrospinning technology and hyaluronic acid modification. A reactive oxygen species responsive prodrug of gambogic acid (GB) and a potent STING agonist (CDN) are coloaded in the core-shell structure of the membrane, which endows the loaded drug with sustained and sequential release patterns. The localized delivery of GB and CDN can selectively induce efficient immunogenic cell death of cancer cells and then evoke the systemic anticancer immunity by activating the Cyclic GMP-AMP (cGAMP) synthase/STING pathway. As-designed "STING" membrane not only safely prevents tumor recurrence through the synergistic chemoimmunotherapy but also efficiently avoids the post-surgery tissue adhesion, facilitating the clinical intervention of CRC.

Robust natural graphite-based bulk graphites with nanodiamond-containing fibrous nanofiller as reinforcement by electrohydrodynamic processing

One-dimensional (1D) structures, such as carbon nanotubes and carbon fibers, used as reinforcements in advanced carbon materials, have been greatly appreciated but facing with some significant challenges of dispersion and interfacial bonding. We utilized electrospinning technology to create a new 1D nanofiller. This material is a superfine fiber composed of polyacrylonitrile (PAN) with a high nanodiamond (ND) content of 75 %, which is referred to as PDNF. During the preparation process, these nanofillers were blended with natural flake graphite (NFG) through electro-spraying. The as-prepared mixture served as the precursor powder sintered into NFG-based high-strength bulk graphite (HPG). During spark plasma sintering at 1800 °C, fibrous PDNF undergoes a phase transformation of diamond to graphite, with onion carbon pinning into and markedly reducing cleavage along the (002) plane of NFG, foundational to the high strength of NFG-based HPG. The PDNF's fiber-like structure and NFG's flake structure greatly increase the interfacial area between the matrix and reinforcement. Furthermore, the PDNF excels at blunting and deflecting cracks, thus bolstering the NFG-based HPG's overall resistance to crack propagation. The density, Young's modulus, and flexural strength of the as-prepared NFG-based HPG achieve 1.65 g/cm3, 17.4 GPa, and 145 MPa, respectively. Most importantly, this process can be a general approach for other high-performance composite materials.

Advancing lithium-ion battery technology with electrospun PVDF-HFP/SiO2 nanocomposite electrolyte membrane and CuCo2O4 high-performance anode material

Electrospinning technology represents a rapid, cost-effective, and secure method for fabricating separators designed for lithium-ion batteries. Within this study, we employed electrospinning technology to craft a PVDF-HFP-SiO2 nanofiber membrane. Throughout various characterizations, this membrane exhibited commendable mechanical attributes, with a maximum tensile stress reaching approximately 11.5 MPa and a maximum tensile strain of 156.3 %. Additionally, it demonstrated exceptional thermal stability, as evidenced by a degradation temperature reaching 450 °C. Simultaneously, we developed a novel flower-like CuCo2O4 anode material directly grown on a 3D nickel foam substrate, eliminating the need for a binder. Electrochemical assessments conducted on cells assembled with nanofiber membrane and CuCo2O4 anode revealed heightened ionic conductivity, with an interfacial resistance of 40 Ω·cm2, alongside exceptional capacity and cycling performance which maintained a discharge capacity of 613 mA h g−1 after 50 cycles, with a Coulombic efficiency consistently above ∼98 %. The enhanced electrochemical performance can be attributed to several factors, including the distinctive flower-shaped electrode, which provides a more extensive network of ion and electron transport channels. Additionally, the porous nanofiber separator, complemented by the presence of doped ceramic particles, plays a vital role in augmenting performance.

Large-Scale Wearable Textile-Based Sweat Sensor with High Sensitivity, Rapid Response, and Stable Electrochemical Performance.

Textile-based sweat sensors display great potential to enhance wearable comfort and health monitoring; however, their widespread application is severely hindered by the intricate manufacturing process and electrochemical characteristics. To address this challenge, we combined both impregnation coating technology and conjugated electrospinning technology to develop an electro-assisted impregnation core-spinning technology (EAICST), which enables us to simply construct a sheath-core electrochemical sensing yarn (TPFV/CPP yarn) via coating PEDOT:PSS-coated carbon fibers (CPP) with polyurethane (TPU)/polyacrylonitrile (PAN)/poloxamer (F127)/valinomycin as shell. The TPFV/CPP yarn was sewn into the fabric and integrated with a sensor to achieve a detachable feature and efficiently monitor K+ levels in sweat. By introducing EAICST, a speed of 10 m/h can be realized in the continuous preparation of the TPFV/CPP yarn, while the interconnected pores in the yarn sheath enable it to quickly capture and diffuse sweat. Besides, the sensor exhibited excellent sensitivity (54.26 mV/decade), fast response (1.7 s), anti-interference, and long-term stability (5000 s or more). Especially, it also possesses favorable washability and wear resistance properties. Taken together, this study provides a crucial technical foundation for the development of advanced wearable devices designed for sweat analysis.

In-situ polarized coaxial PVDF/PL nanofiber filtration membrane with high efficiency, low resistance and antimicrobial properties

Aerosols are prone to breed bacteria on air filtration materials so as to cause secondary air pollution, especially carrying bacteria and viruses. This paper utilized coaxial electrospinning technology with traditional Chinese medicine Physalis alkekengi Linn as the core layer antibacterial material and polyvinylidene fluoride/polyacrylonitrile mixed solution as the shell layer material. Nonsolvent phase separation technology was employed to prepare the porous shell layer, achieving sustained slow-release and long-lasting antibacterial effects from the core P. alkekengi Linn. In addition, an in-situ polarization technology from high voltage in electrospinning process was adopted to achieve permanent polarization of polyvinylidene fluoride, which changed from α-crystal to β-crystal. Using the electrostatic charge adsorption effect and the ultra-fine pore size screening of the nanofiber membrane, high-efficiency and low-resistance filtration of aerosols above 0.3 μm was achieved (99.98% filtration efficiency and filtration resistance less than 25 Pa). It can be widely used in the field of air filtration and protection in high-risk environments such as stations, schools, and hospitals, achieving long-lasting antibacterial, high-efficiency, and low-resistance air filtration and protection.

Rapid, Massive, and Green Synthesis of Polyoxometalate-Based Metal-Organic Frameworks to Fabricate POMOF/PAN Nanofiber Membranes for Selective Filtration of Cationic Dyes.

Developing high-efficiency membrane materials for the rapid removal of organic dyes is crucial but remains a challenge. Polyoxometalates (POMs) clusters with anionic structures are promising candidates for the removal of cationic dyes via electrostatic interactions. However, their shortcomings, such as their solubility and inability to be mass-produced, hinder their application in water pollution treatment. Here, we propose a simple and green strategy utilizing the room temperature stirring method to mass produce nanoscale polyoxometalate-based metal-organic frameworks (POMOFs) with porous rhomboid-shaped dodecahedral and hexagonal prism structures. The products were labeled as POMOF1 (POMOF-PW12) and POMOF2 (POMOF-PMo12). Subsequently, a series of x wt% POMOF1/PAN (x = 0, 3, 5, and 10) nanofiber membranes (NFMs) were prepared using electrospinning technology, where polyacrylonitrile (PAN) acts as a "glue" molecule facilitating the bonding of POMOF1 nanoparticles. The as-prepared samples were comprehensively characterized and exhibited obvious water stability, as well as rapid selective adsorption filtration performance towards cationic dyes. The 5 wt% POMOF1/PAN NFM possessed the highest removal efficiency of 96.7% for RhB, 95.8% for MB, and 86.4% for CV dyes, which realized the selective separation over 95% of positively charged dyes from the mixed solution. The adsorption mechanism was explained using FT-IR, SEM, Zeta potential, and adsorption kinetics model, which proved that separation was determined via electrostatic interaction, hydrogen bonding, and π-π interactions. Moreover, the POMOF1/PAN membrane presented an outstanding recoverable and stable removal rate after four cycles. This study provides a new direction for the systematic design and manufacture of membrane separation materials with outstanding properties for contaminant removal.

High performance bimetallic ZIF-CoZn@PVDF-HFP composite nanofiber membrane for membrane distillation based on coaxial electrospinning technology

Membrane Distillation (MD) technology stands out for its cost-effectiveness and sustainability in diverse applications, such as high-salinity wastewater treatment and seawater desalination. However, conventional MD membranes frequently encounter challenges associated with inadequate permeate flux and insufficient anti-wetting performance. In the present study, we fabricated a series of ZIF-CoZn@PVDF-HFP composite nanofiber membranes with a core–shell structure via coaxial electrospinning. Here, PVDF-HFP functions as the core, while a blend of bimetallic Zeolitic imidazolate framework ZIF-CoZn nanoparticles and PVDF-HFP constitutes the shell. Through the utilization of the coaxial technology, functional nanoparticles achieve uniform and stably dispersed on the nanofiber surface, leading to the creation of a secondary rough structure in addition to the inherent roughness of single-nozzle electrospinning. This results in a surface with a 3D-hierarchical structure. The significantly amplifies the evaporation area on the surface of the composite nanofiber membrane, thereby bolstering the permeate flux in the MD process. Additionally, the incorporation of bimetallic ZIF-CoZn nanoparticles, recognized for their superior hydrophobicity and low thermal conductivity, improves the anti-wetting and heat-insulating properties of the composite nanofiber membrane, further advancing permeate flux performance. Using a 35 g L−1 NaCl as the feed solution, the optimal 1 % ZIF-CoZn@PVDF-HFP composite nanofiber membrane demonstrated a permeate flux of 21.8 L m−2 h−1, coupled with a salt rejection rate exceeding 99.9 %. Even during long-term MD testing, it maintained excellent insulation and anti-wetting capabilities. Our research offers a convenient and effective approach for fabricating anti-wetting composite nanofiber membranes.

Solid-State Electrolytes by Electrospinning Techniques for Lithium Batteries.

Solid-state lithium batteries (SSLBs) are regarded as next-generation energy storage devices because of their advantages in terms of safety and energy density. However, the poor interfacial compatibility and low ionic conductivity seriously hinder their development. Electrospinning is considered as a promising method for fabricating solid-state electrolytes (SSEs) with controllable nanofiber structures, scalability, and cost-effectiveness. Numerous efforts are dedicated to electrospinning SSEs with high ionic conductivity and strong interfacial compatibility, but a comprehensive summary is lacking. Here, the history of electrospinning SSEs is overeviewed and introduce the electrospinning mechanism, followed by the manipulation of electrospun nanofibers and their utilization in SSEs, as well as various methods to improve the ionic conductivity of SSEs. Finally, new perspectives aimed at enhancing the performance of SSEs membranes and facilitating their industrialization are proposed. This review aims to provide a comprehensive overview and future perspective on electrospinning technology in SSEs, with the goal of guiding the further development of SSLBs.

Electrospun nanofibrous mats loaded with gemcitabine and cisplatin suppress bladder tumor growth by improving the tumor immune microenvironment

The perplexing issues related to positive surgical margins and the considerable negative consequences associated with systemic chemotherapy have posed ongoing challenges for clinicians, especially when it comes to addressing bladder cancer treatment. The current investigation describes the production of nanocomposites loaded with gemcitabine (GEM) and cisplatin (CDDP) through the utilization of electrospinning technology. In vitro and in vivo studies have provided evidence of the strong effectiveness in suppressing tumor advancement while simultaneously reducing the accumulation of chemotherapy drugs within liver and kidney tissues. Mechanically, the GEM and CDDP-loaded electrospun nanocomposites could effectively eliminate myeloid-derived suppressor cells (MDSCs) in tumor tissues, and recruit CD8+ T cells and NKp46+ NK cells to kill tumor cells, which can also effectively inhibit tumor microvascular formation. Our investigation into the impact of localized administration of chemotherapy through GEM and CDDP-loaded electrospun nanocomposites on the tumor microenvironment will offer novel insights for tackling tumors.Graphical abstractDrug-loaded electrospun nanofibrous mats suppress bladder tumor growth by improving the tumor immune microenvironment.

Puerarin-Loaded Electrospun Patches with Anti-Inflammatory and Pro-Collagen Synthesis Properties for Pelvic Floor Reconstruction.

Pelvic organ prolapse (POP) is one of the most common pelvic floor dysfunction disorders worldwide. The weakening of pelvic connective tissues initiated by excessive collagen degradation is a leading cause of POP. However, the patches currently used in the clinic trigger an unfavorable inflammatory response, which often leads to implantation failure and the inability to simultaneously reverse progressive collagen degradation. Therefore, to overcome the present challenges, a new strategy is applied by introducing puerarin (Pue) into poly(l-lactic acid) (PLLA) using electrospinning technology. PLLA improves the mechanical properties of the patch, while Pue offers intrinsic anti-inflammatory and pro-collagen synthesis effects. The results show that Pue is released from PLLA@Pue in a sustained manner for more than 20days, with a total release rate exceeding 80%. The PLLA@Pue electrospun patches also show good biocompatibility and low cytotoxicity. The excellent anti-inflammatory and pro-collagen synthesis properties of the PLLA@Pue patch are demonstrated both in vitro in H2O2-stimulated mouse fibroblasts and in vivo in rat abdominal wall muscle defects. Therefore, it is believed that this multifunctional electrospun patch integrating anti-inflammatory and pro-collagen synthesis properties can overcome the limitations of traditional patches and has great prospects for efficient pelvic floor reconstruction.

Polycaprolactone/chitosan electrospun nanofibrous membranes loaded Chinese yam polysaccharide for active food packaging

In this study, the electrospun nanofibrous membranes were prepared by blending electrospinning technology with Polycaprolactone/Chitosan (PCL/CS) as a spinning carrier and Chinese Yam Polysaccharide (CYP) as active material. The membranes were characterized and antimicrobial tested to determine whether they have potential value as food packaging. The results of SEM showed that the nanofiber membranes with different concentrations had good fiber morphology, the average fiber diameter was 313 ± 178 nm–426 ± 237 nm, and the PDI value indicated that the nanofiber was polydisperse. The addition of CYP enhanced the hydrophilicity and water solubility of the nanofiber membranes, but the mechanical strength of the membranes decreased. The spectra of FTIR and DSC indicated that the PCL/CS nanofiber membrane successfully loaded CYP, and the 4 % CYP nanofiber membrane had the best thermal stability. In vitro release tests also showed that most fibrous membranes still released CYP (56.4–81.7 %) after 240 h. In addition, the antibacterial zone diameter of PCL/CS/10 % CYP nanofiber membrane against Escherichia coli and Staphylococcus aureus was 22.01 ± 1.23 mm and 18.40 ± 0.84 mm, respectively, showing obvious antibacterial effect. In the tomato antibacterial experiment, PCL/CS/10 % CYP nanofiber membrane effectively delayed the water-loss rot of cherry tomato and kept the weight loss rate of fruit at 17.6 ± 0.14 %. The results showed that PCL/CS/10% CYP nanofiber membrane had the best effect as active food packaging.

Porous nanofibers and micro-pyramid structures array for high-performance flexible pressure sensors

Flexible pressure sensors have attracted extensive research interest as smart wearable devices’ core components. However, developing flexible pressure sensors with high sensitivity and wide pressure detection range remains a great challenge. Utilizing electrospinning and mould transfer technology, this paper presents a novel ‘sandwich’ flexible pressure sensor composed of a sensitive layer of poly (lactic acid) (PLA) porous nanofiber network film and electrodes made of polydimethylsiloxane (PDMS) micro-pyramid structure array film. Through ultrasonic treatment, carbon black particles penetrate into the PLA porous nanofiber film, which effectively enhances the conductivity of the PLA film. Due to the complex conductive pathways formed by the ultra-high specific surface area of the PLA porous nanofibers and the three-dimensional amplification structure of the PDMS micro-pyramid arrays, the sensor has a high sensitivity of 54.06 kPa−1, a wide detection range of 0–56 kPa, an ultra-low detection limit of 2.5 Pa and excellent durability (10000 cycles). Impressively, the sensor is able to accurately monitor various physiological activities of the human body in real time, which is believed to be a strong impetus for the development of the next generation of wearable products.

Advanced Electrospinning Technology Applied to Polymer-Based Sensors in Energy and Environmental Applications.

Due to its designable nanostructure and simple and inexpensive preparation process, electrospun nanofibers have important applications in energy collection, wearable sports health detection, environmental pollutant detection, pollutant filtration and degradation, and other fields. In recent years, a series of polymer-based fiber materials have been prepared using this method, and detailed research and discussion have been conducted on the material structure and performance factors. This article summarizes the effects of preparation parameters, environmental factors, a combination of other methods, and surface modification of electrospinning on the properties of composite nanofibers. Meanwhile, the effects of different collection devices and electrospinning preparation parameters on material properties were compared. Subsequently, it summarized the material structure design and specific applications in wearable device power supply, energy collection, environmental pollutant sensing, air quality detection, air pollution particle filtration, and environmental pollutant degradation. We aim to review the latest developments in electrospinning applications to inspire new energy collection, detection, and pollutant treatment equipment, and achieve the commercial promotion of polymer fibers in the fields of energy and environment. Finally, we have identified some unresolved issues in the detection and treatment of environmental issues with electrospun polymer fibers and proposed some suggestions and new ideas for these issues.

One-Step Prepared Multifunctional Polyacrylonitrile/MIL-100(Fe) Membrane with High-Density Porous Fibers for Efficient Dye/Oil Wastewater Remediation.

With environmental pollution becoming more serious, developing efficient treatment technologies for all kinds of organic wastewater has become the focus of current research. In this work, the coaxial electrospinning technology was used to one-step fabricate a porous and underwater superoleophobic polyacrylonitrile nanofibrous membrane with an Fe-based metal-organic framework (MIL-100(Fe)). Benefiting from the synergistic effect of two jets, the nanofibers are smaller and denser, which prompt the exposure of more nanomaterial additives (MIL-100(Fe)). The BET surface area increased to 202.888 m2/g, and the membranes demonstrated outstanding underwater superoleophobicity. Moreover, compared with traditional blended matrix membranes by the single-axis method, separation of the modifier and membrane matrix material by coaxial methods also maintained excellent mechanical properties, which enhanced Young's modulus 3.4 times (∼1.34 MPa). As a result, facing soluble dyes, the porous C-PAN/MIL-100(Fe) membrane can demonstrate outstanding and fast adsorptive property (the Qm of MB and CR reached 44.71 and 88.74 mg g-1, respectively). For oily emulsion, the hydrophilic and oleophobic nanofibrous reticular surface provided excellent separation performance (flux: 1124.0-1549.3 L m-2 h-1, R > 98%). Moreover, the porous and underwater superoleophobic C-PAN/MIL-100(Fe)-0.5 membrane can synchronously purify the dye/oil mixture emulsions by one-step filtration. Based on the above performance, we believe that the modified nanofibrous membrane prepared by one-step coaxial electrospinning technology can promote more studies of the development of membrane preparation technology in the field of oily wastewater treatment.

Nanofibrous Porous Organic Polymers and Their Derivatives: From Synthesis to Applications.

Engineering porous organic polymers (POPs) into 1D morphology holds significant promise for diverse applications due to their exceptional processability and increased surface contact for enhanced interactions with guest molecules. This article reviews the latest developments in nanofibrous POPs and their derivatives, encompassing porous organic polymer nanofibers, their composites, and POPs-derived carbon nanofibers. The review delves into the design and fabrication strategies, elucidates the formation mechanisms, explores their functional attributes, and highlights promising applications. The first section systematically outlines two primary fabrication approaches of nanofibrous POPs, i.e., direct bulk synthesis and electrospinning technology. Both routes are discussed and compared in terms of template utilization and post-treatments. Next, performance of nanofibrous POPs and their derivatives are reviewed for applications including water treatment, water/oil separation, gas adsorption, energy storage, heterogeneous catalysis, microwave absorption, and biomedical systems. Finally, highlighting existent challenges and offering future prospects of nanofibrous POPs and their derivatives are concluded.

Nitrogen-doped carbon nanofiber loaded MOF-derived NiCo bimetallic nanoparticles accelerate the redox transformation of polysulfide for lithium- sulfur batteries

In the electrochemical study of lithium-sulfur (Li-S) batteries, the slow kinetics of the sulfur reduction reaction (SRR) leading to severe shuttle effect of polysulfides remains a major challenge. Catalysts with bimetallic nanoparticles have higher adsorption affinity for lithium polysulfides and hold great potential in improving reaction kinetics. In this study, a nitrogen-doped carbon nanofiber carrier was prepared using high-voltage electrospinning technology, and through in-situ growth and high-temperature pyrolysis process, the carrier material was uniformly loaded with active sites of NiCo bimetallic nanoparticles derived from Metal-organic framework (MOF), aiming to improve the kinetics of sulfur oxidation and reduction and reduce the severe shuttle effect of soluble polysulfides. At the same time, polymethyl methacrylate was added to adjust the pore structure of the carbon nanofibers to form an ideal independent sulfur cathode porous conductive carbon network for rapid ion transport to prevent Li2S deposition and alleviate the volume change during lithiation/delithiation process. Experimental results show that the synergistic catalytic effect of bimetallic nanoparticles can not only rapidly anchor lithium polysulfides throughout the entire reaction process of Li-S batteries, but also reduce the resistance during the reaction process, accelerating the conversion of lithium polysulfides to Li2S deposition. It demonstrates outstanding electrochemical performance, with a first-cycle discharge specific capacity as high as 1431.7 mAh g−1 at a 0.2 C rate, and a Coulombic efficiency of 96%. After 500 cycles, its capacity still maintains at 628.5 mAh g−1, with a decay rate of only 0.11% per cycle. This study provides a feasible insight into the synergistic catalysis of MOF-derived metal nanoparticles, which has important guiding significance and potential impact on the catalysis of Li-S batteries by bimetallic nanoparticles with an independent sulfur cathode structure, and is expected to accelerate the industrialization process of Li-S batteries.

Electrospun multi-chamber core-shell nanofibers and their controlled release behaviors: A review.

Core-shell structure is a concentric circle structure found in nature. The rapid development of electrospinning technology provides more approaches for the production of core-shell nanofibers. The nanoscale effects and expansive specific surface area of core-shell nanofibers can facilitate the dissolution of drugs. By employing ingenious structural designs and judicious polymer selection, specialized nanofiber drug delivery systems can be prepared to achieve controlled drug release. The synergistic combination of core-shell structure and materials exhibits a strong strategy for enhancing the drug utilization efficiency and customizing the release profile of drugs. Consequently, multi-chamber core-shell nanofibers hold great promise for highly efficient disease treatment. However, little attention concentration is focused on the effect of multi-chamber core-shell nanofibers on controlled release of drugs. In this review, we introduced different fabrication techniques for multi-chamber core-shell nanostructures, including advanced electrospinning technologies and surface functionalization. Subsequently, we reviewed the different controlled drug release behaviors of multi-chamber core-shell nanofibers and their potential needs for disease treatment. The comprehensive elucidation of controlled release behaviors based on electrospun multi-chamber core-shell nanostructures could inspire the exploration of novel controlled delivery systems. Furthermore, once these fibers with customizable drug release profiles move toward industrial mass production, they will potentially promote the development of pharmacy and the treatment of various diseases. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies.

A Colorimetric Nanofiber Film Based on Ethyl Cellulose/Gelatin/Purple Sweet Potato Anthocyanins for Monitoring Pork Freshness.

In this study, colorimetric indicator nanofiber films based on ethyl cellulose (EC)/gelatin (G) incorporating purple sweet potato anthocyanins (PSPAs) were designed via electrospinning technology for monitoring and maintaining the freshness of pork. The film presented good structural integrity and stability in a humid environment with water vapor permeability (WVP) of 6.07 ± 0.14 × 10-11 g·m-1s-1Pa-1 and water contact angle (WCA) of 81.62 ± 1.43°. When PSPAs were added into the nanofiber films, the antioxidant capacity was significantly improved (p < 0.05) with a DPPH radical scavenging rate of 68.61 ± 1.80%. The nanofiber films showed distinguishable color changes as pH changes and was highly sensitive to volatile ammonia than that of casting films. In the application test, the film color changed from light pink (fresh stage) to light brown (secondary freshness stage) and then to brownish green (spoilage stage), indicating that the nanofiber films can be used to detect the real-time freshness of pork during storage. Meanwhile, it could prolong the shelf life of pork by inhibiting the oxidation degree. Hence, these results suggested that the EC/G/PSPA film has promising future for monitoring freshness and extending shelf life of pork.

Photosynthetic nano fibers: Living microalgae packaging into polyvinyl alcohol nanofibers using an electrospinning method

AbstractAlthough microalgae are often studied for their biochemical extracts, utilizing them in a viable state opens new avenues for sustainable oxygenation in various systems. This study addresses the challenges of maintaining system homeostasis and presents an effective method for immobilizing live microalgae within poly(vinyl alcohol) (PVA) nanofibers using electrospinning technology. Characterization techniques, including scanning electron microscopy (SEM), fluorescence microscopy, Fourier‐transform infrared (FTIR) spectroscopy, and differential scanning calorimetry (DSC), were used to validate successful immobilization. Rheological studies were performed to investigate the influence of microalgae on the fiber morphology. Changing the PVA concentration, the fiber diameter could be regulated between 150 and 650 nm in the spinnable range. The addition of microalgae to the solution increased the viscosity of the prepared solution and reduced the resulting fiber diameter by approximately 2/3. Our results show that PVA nanofibers effectively encapsulate living microalgae and allow for sustained transport of nutrients and metabolites. The photosynthetic efficacy of the encapsulated microalgae was evaluated using dissolved oxygen measurements and showed two times higher rates of oxygen production and consumption compared with a film‐based approach. Our results show that PVA nanofibers effectively encapsulated living microalgae and allowed for the sustained transport of nutrients and metabolites. This innovative methodology provides a robust platform for immobilizing living microorganisms, with broad implications for applications ranging from regenerative medicine to sustainable agriculture.

Direct electrospinning of reconstructable PVDF-TrFE nanofibrous mat onto conductive cement nanocomposite for triboelectricity-assisted net zero energy structure

As interest in harvesting green energy and utilizing renewable energy in the building sector has increased, the concept of Net Zero Energy Structure (NZES) has been highlighted. In this study, a strategy to develop the sustainable triboelectricity-assisted NZES is proposed. The multi-walled Carbon nanotube (MWCNT)-incorporated Cement Composite (CCC) is adopted as the structural/electrical member of the triboelectric nanogenerator (TENG) and the polyvinylidene difluoride-trifluoroethylene (PVDF-TrFE) nanofiber is directly electrospun onto the surface of CCC to act as the contact layer of the CCC-based TENG. The optimal concentration of incorporated MWCNT, CMC, is determined to be 1 vol%, considering the compressive strength and electrical property of CCC. The conditions of the electrospinning process for configuring the electrospun PVDF-TrFE nanofibrous mat on the surfaces of CCCs with various shapes are investigated. The electrical output performance of the CCC-TENG is characterized by varying the various environmental and operational parameters. The direct electrospun PVDF-TrFE nanofibrous mat on the CCC-TENG significantly increases the output voltage to approximately 6 times that of flat TENG. The maximum peak power generated from CCC-TENG reaches 60.9 μW when the connected load resistance is 50 MΩ. Furthermore, as a proof-of-concept, the reconstructability of the PVDF-TrFE nanofibrous mat using the direct electrospinning process, as well as the restorations in terms of surface micro/nanostructures and electrical output performance, are demonstrated. Given the wide range of applications of cement and various functionalities of direct electrospinning technology, the sustainable triboelectricity-assisted NZES with CCC and direct electrospun PVDF-TrFE nanofibrous mat is expected to have great potential to take a step toward the development of sustainable Net Zero Energy Community in the future.