Electrospun nanofiber-based cancer sensors: A review

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.

Advances in Biomedical Applications of Solution Blow Spinning

In recent years, Solution Blow Spinning (SBS) has emerged as a new technology for the production of polymeric, nanocomposite, and ceramic materials in the form of nano and microfibers, with similar features to those achieved by other procedures. The advantages of SBS over other spinning methods are the fast generation of fibers and the simplicity of the experimental setup that opens up the possibility of their on-site production. While producing a large number of nanofibers in a short time is a crucial factor in large-scale manufacturing, in situ generation, for example, in the form of sprayable, multifunctional dressings, capable of releasing embedded active agents on wounded tissue, or their use in operating rooms to prevent hemostasis during surgical interventions, open a wide range of possibilities. The interest in this spinning technology is evident from the growing number of patents issued and articles published over the last few years. Our focus in this review is on the biomedicine-oriented applications of SBS for the production of nanofibers based on the collection of the most relevant scientific papers published to date. Drug delivery, 3D culturing, regenerative medicine, and fabrication of biosensors are some of the areas in which SBS has been explored, most frequently at the proof-of-concept level. The promising results obtained demonstrate the potential of this technology in the biomedical and pharmaceutical fields.

Fabrication of an electrospun polycaprolactone substrate for colorimetric bioassays

Colorimetric assays rely on detecting colour changes to measure the concentration of target molecules. Paper substrates are commonly used for the detection of biomarkers due to their availability, porous structure, and capillarity. However, the morphological and mechanical properties of paper, such as fibre diameter, pore size, and tensile strength, cannot be easily tuned to meet the specific requirements of colorimetric sensors, including liquid capacity and reagent immobilisation. As an alternative to paper materials, biodegradable polymeric membranes made of electrospun polycaprolactone (PCL) fibres can provide various tunable properties related to fibre diameter and pore size.We aimed to obtain a glucose sensor substrate for colorimetric sensing using electrospinning with PCL. A feeding solution was created by mixing PCL/chloroform and 3,3',5',5'-tetramethylbenzidine (TMB)/ethanol solutions. This solution was electrospun to fabricate a porous membrane composed of microfibres consist of PCL and TMB. The central area of the membrane was made hydrophilic through air plasma treatment, and it was subsequently functionalized with a solution containing glucose oxidase, horseradish peroxidase, and trehalose.The sensing areas were evaluated by measuring colour changes in glucose solutions of varying concentrations. The oxidation reactions of glucose and TMB in sensor substrates were recorded and analysed to establish the correlation between different glucose concentrations and colour changes. For comparison, conventional paper substrates prepared with same parameters were evaluated alongside the electrospun PCL substrates. As a result, better immobilization of reagents and higher sensitivity of glucose were achieved with PCL substrates, indicating their potential usage as a new sensing substrate for bioassays.

Stimuli-responsive electrospun nanofibers for drug delivery, cancer therapy, wound dressing, and tissue engineering

The stimuli-responsive nanofibers prepared by electrospinning have become an ideal stimuli-responsive material due to their large specific surface area and porosity, which can respond extremely quickly to external environmental incitement. As an intelligent drug delivery platform, stimuli-responsive nanofibers can efficiently load drugs and then be stimulated by specific conditions (light, temperature, magnetic field, ultrasound, pH or ROS, etc.) to achieve slow, on-demand or targeted release, showing great potential in areas such as drug delivery, tumor therapy, wound dressing, and tissue engineering. Therefore, this paper reviews the recent trends of stimuli-responsive electrospun nanofibers as intelligent drug delivery platforms in the field of biomedicine.

A Sequential Electrospinning of a Coaxial and Blending Process for Creating Double-Layer Hybrid Films to Sense Glucose

This study presents a glucose biosensor based on electrospun core-sheath nanofibers. Two types of film were fabricated using different electrospinning procedures. Film F1 was composed solely of core-sheath nanofibers fabricated using a modified coaxial electrospinning process. Film F2 was a double-layer hybrid film fabricated through a sequential electrospinning and blending process. The bottom layer of F2 comprised core-sheath nanofibers fabricated using a modified process, in which pure polymethacrylate type A (Eudragit L100) was used as the core section and water-soluble lignin (WSL) and phenol were loaded as the sheath section. The top layer of F2 contained glucose oxidase (GOx) and gold nanoparticles, which were distributed throughout the polyvinylpyrrolidone K90 (PVP K90) nanofibers through a single-fluid blending electrospinning process. The study investigated the sequential electrospinning process in detail. The experimental results demonstrated that the F2 hybrid film had a higher degradation efficiency of β-D-glucose than F1, reaching a maximum of over 70% after 12 h within the concentration range of 10-40 mmol/L. The hybrid film F2 is used for colorimetric sensing of β-D-glucose in the range of 1-15 mmol/L. The solution exhibited a color that deepened gradually with an increase in β-D-glucose concentration. Electrospinning is flexible in creating structures for bio-cascade reactions, and the double-layer hybrid film can provide a simple template for developing other sensing nanomaterials.

Advances in the Application of Electrospun Drug-Loaded Nanofibers in the Treatment of Oral Ulcers

Oral ulcers affect oral and systemic health and have high prevalence in the population. There are significant individual differences in the etiology and extent of the disease among patients. In the treatment of oral ulcers, nanofiber films can control the drug-release rate and enable long-term local administration. Compared to other drug-delivery methods, nanofiber films avoid the disadvantages of frequent administration and certain side effects. Electrospinning is a simple and effective method for preparing nanofiber films. Currently, electrospinning technology has made significant breakthroughs in energy-saving and large-scale production. This paper summarizes the polymers that enable oral mucosal adhesion and the active pharmaceutical ingredients used for oral ulcers. Moreover, the therapeutic effects of currently available electrospun nanofiber films on oral ulcers in animal experiments and clinical trials are investigated. In addition, solvent casting and cross-linking methods can be used in conjunction with electrospinning techniques. Based on the literature, more administration systems with different polymers and loading components can be inspired. These administration systems are expected to have synergistic effects and achieve better therapeutic effects. This not only provides new possibilities for drug-loaded nanofibers but also brings new hope for the treatment of oral ulcers.

Electrospun nanofibrous membrane for biomedical application

Electrospinning is a simple, cost-effective, flexible, and feasible continuous micro-nano polymer fiber preparation technology that has attracted extensive scientific and industrial interest over the past few decades, owing to its versatility and ability to manufacture highly tunable nanofiber networks. Nanofiber membrane materials prepared using electrospinning have excellent properties suitable for biomedical applications, such as a high specific surface area, strong plasticity, and the ability to manipulate their nanofiber components to obtain the desired properties and functions. With the increasing popularity of nanomaterials in this century, electrospun nanofiber membranes are gradually becoming widely used in various medical fields. Here, the research progress of electrospun nanofiber membrane materials is reviewed, including the basic electrospinning process and the development of the materials as well as their biomedical applications. The main purpose of this review is to discuss the latest research progress on electrospun nanofiber membrane materials and the various new electrospinning technologies that have emerged in recent years for various applications in the medical field. The application of electrospun nanofiber membrane materials in recent years in tissue engineering, wound dressing, cancer diagnosis and treatment, medical protective equipment, and other fields is the main topic of discussion in this review. Finally, the development of electrospun nanofiber membrane materials in the biomedical field is systematically summarized and prospects are discussed. In general, electrospinning has profound prospects in biomedical applications, as it is a practical and flexible technology used for the fabrication of microfibers and nanofibers.

This review summarizes recent research on the application of electrospun nanofiber membranes as tissue engineering materials for the cardiovascular system, motor system, nervous system, and other clinical aspects.

Research on the application of electrospun nanofiber membrane materials as protective products is discussed in the context of the current epidemic situation.

Examples and analyses of recent popular applications in tissue engineering, wound dressing, protective products, and cancer sensors are presented.

Surface Reconstruction on Electro-Spun PVA/PVP Nanofibers by Water Evaporation

Tailoring the secondary surface morphology of electro-spun nanofibers has been highly desired, as such delicate structures equip nanofibers with distinct functions. Here, we report a simple strategy to directly reconstruct the surface of polyvinyl alcohol/polyvinylpyrrolidone (PVA/PVP) nanofibers by water evaporation. The roughness and diameter of the nanofibers depend on the temperature during vacuum drying. Surface changes of the nanofibers from smooth to rough were observed at 55 °C, with a significant drop in nanofiber diameter. We attribute the formation of the secondary surface morphology to the intermolecular forces in the water vapor, including capillary and the compression forces, on the basis of the results from the Fourier-transform infrared (FTIR) and X-ray photoelectron (XPS) spectroscopy. The strategy is universally effective for various electro-spun polymer nanofibers, thus opening up avenues toward more detailed and sophisticated structure design and implementation for nanofibers.

A highly stable and sensitive ethanol sensor based on Ru-decorated 1D WO3 nanowires

Decorating materials with noble metal catalysts is an effective method for optimizing the sensing performance of sensors based on tungsten trioxide (WO₃) nanowires. Ruthenium (Ru) exhibits excellent catalytic activity for oxygen adsorption/desorption and chemical reactions between gases and adsorbed oxygen. Herein, small Ru nanoparticles were uniformly distributed on the surface of one-dimensional WO₃ nanowires. The nanowires were prepared by the electrospinning method through an ultraviolet (UV) irradiation process, and decoration with Ru did not change their morphology. A sensor based on 4% Ru nanowires (NWs) shows the highest response (∼120) to 100 ppm ethanol, which was increased around 47 times, and the lowest ethanol detection limit (221 ppb) at a lower temperature (200 °C) displays outstanding repeatability and stability even after 45 days or in higher-humidity conditions. Moreover, it also has faster response–recovery features. The improvement in the sensing performance was attributed to the stable morphology of the nanowires, the sensitization effect of Ru, the catalytic effect of RuO₂ and the optimal atomic utilization efficiency. This work offers an effective and promising strategy for promoting the ethanol sensing performance of WO₃.

Decorating Ru does not effect the morphology of NWs, increased the oxygen vacancies, adsorbed oxygen. This strategy results in a better sensing performance (∼120 to 100 ppm ethanol was increased around 47 times at 200 °C) and humidity resistance.

Perspective on Nanofiber Electrochemical Sensors: Design of Relative Selectivity Experiments

The use of nanofibers creates the ability for non-enzymatic sensing in various applications and greatly improves the sensitivity, speed, and accuracy of electrochemical sensors for a wide variety of analytes. The high surface area to volume ratio of the fibers as well as their high porosity, even when compared to other common nanostructures, allows for enhanced electrocatalytic, adsorptive, and analyte-specific recognition mechanisms. Nanofibers have the potential to rival and replace materials used in electrochemical sensing. As more types of nanofibers are developed and tested for new applications, more consistent and refined selectivity experiments are needed. We applied this idea in a review of interferant control experiments and real sample analyses. The goal of this review is to provide guidelines for acceptable nanofiber sensor selectivity experiments with considerations for electrocatalytic, adsorptive, and analyte-specific recognition mechanisms. The intended presented review and guidelines will be of particular use to junior researchers designing their first control experiments, but could be used as a reference for anyone designing selectivity experiments for non-enzymatic sensors including nanofibers. We indicate the importance of testing both interferants in complex media and mechanistic interferants in the selectivity analysis of newly developed nanofiber sensor surfaces.

The Food-Materials Nexus: Next Generation Bioplastics and Advanced Materials from Agri-Food Residues

The most recent strategies available for upcycling agri-food losses and waste (FLW) into functional bioplastics and advanced materials are reviewed and the valorization of food residuals are put in perspective, adding to the water-food-energy nexus. Low value or underutilized biomass, biocolloids, water-soluble biopolymers, polymerizable monomers, and nutrients are introduced as feasible building blocks for biotechnological conversion into bioplastics. The latter are demonstrated for their incorporation in multifunctional packaging, biomedical devices, sensors, actuators, and energy conversion and storage devices, contributing to the valorization efforts within the future circular bioeconomy. Strategies are introduced to effectively synthesize, deconstruct and reassemble or engineer FLW-derived monomeric, polymeric, and colloidal building blocks. Multifunctional bioplastics are introduced considering the structural, chemical, physical as well as the accessibility of FLW precursors. Processing techniques are analyzed within the fields of polymer chemistry and physics. The prospects of FLW streams and biomass surplus, considering their availability, interactions with water and thermal stability, are critically discussed in a near-future scenario that is expected to lead to next-generation bioplastics and advanced materials.

The synthesis and characterization of Fe2O3@SiO2-SO3H nanofibers as a novel magnetic core-shell catalyst for formamidine and formamide synthesis

Over the past several decades, the fabrication of novel ceramic nanofibers applicable in different areas has been a frequent focus of scientists around the world. Aiming to introduce novel ceramic core-shell nanofibers as a magnetic solid acid catalyst, Fe2O3@SiO2-SO3H magnetic nanofibers were prepared in this study using a modification of Fe2O3@SiO2 core-shell nanofibers with chlorosulfonic acid to increase the acidic properties of these ceramic nanofibers. The products were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), energy dispersive X-ray spectroscope (EDS), vibrating sample magnetometer (VSM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). The prepared nanofibers were used as catalysts in formamide and formamidine synthesis. The treatment of aqueous formic acid using diverse amines with a catalytic amount of Fe2O3@SiO2-SO3H nanofibers as a reusable, magnetic and heterogeneous catalyst produced high yields of corresponding formamides at room temperature. Likewise, the reaction of diverse amines with triethyl orthoformate led to the synthesis of formamidine derivatives in excellent yields using this novel catalyst. The catalytic system was able to be recovered and reused at least five times without any catalytic activity loss. Thus, novel core-shell nanofibers can act as efficient solid acid catalysts in different organic reactions capable of being reused several times due to their easy separation by applying magnet.

An electrochemical immunosensor modified with titanium IV oxide/polyacrylonitrile nanofibers for the determination of a carcinoembryonic antigen

A highly sensitive electrochemical carcinoembryonic antigen immunosensor based on TiO₂np/polyacrylonitrile nanofibers electrospun on the surface of the discharged battery coal electrode.

Electrospinning for healthcare: recent advancements

This perspective explores recent developments and innovations in the electrospinning technique and their potential applications in biomedicine.

Advances in Functional Polymer Nanofibers: From Spinning Fabrication Techniques to Recent Biomedical Applications

Functional polymeric micro-/nanofibers have emerged as promising materials for the construction of structures potentially useful in biomedical fields. Among all kinds of technologies to produce polymer fibers, spinning methods have gained considerable attention. Herein, we provide a recent review on advances in the design of micro- and nanofibrous platforms via spinning techniques for biomedical applications. Specifically, we emphasize electrospinning, solution blow spinning, centrifugal spinning, and microfluidic spinning approaches. We first introduce the fundamentals of these spinning methods and then highlight the potential biomedical applications of such micro- and nanostructured fibers for drug delivery, tissue engineering, regenerative medicine, disease modeling, and sensing/biosensing. Finally, we outline the current challenges and future perspectives of spinning techniques for the practical applications of polymer fibers in the biomedical field.