The Applications of Ferulic-Acid-Loaded Fibrous Films for Fruit Preservation

Advanced applications of smart electrospun nanofibers in cancer therapy: With insight into material capabilities and electrospinning parameters

Cancer remains a major global health challenge, and despite available treatments, its prognosis remains poor. Recently, researchers have turned their attention to intelligent nanofibers for cancer drug delivery. These nanofibers exhibit remarkable capabilities in targeted and controlled drug release. Their inherent characteristics, such as a high surface area-to-volume ratio, make them attractive candidates for drug delivery applications. Smart nanofibers can release drugs in response to specific stimuli, including pH, temperature, magnetic fields, and light. This unique feature not only reduces side effects but also enhances the overall efficiency of drug delivery systems. Electrospinning, a widely used method, allows the precision fabrication of smart nanofibers. Its advantages include high efficiency, user-friendliness, and the ability to control various manufacturing parameters. In this review, we explore the latest developments in producing smart electrospun nanofibers for cancer treatment. Additionally, we discuss the materials used in manufacturing these nanofibers and the critical parameters involved in the electrospinning process.

Preparation and properties of PCL coaxial electrospinning films with shell loaded with CEO and core coated LEO nanoemulsions

During storage and transportation, the reduction of microbial contamination and management of the exudation of fluids from the fish can effectively mitigate spoilage and degradation of fish fillets. In this work, the coaxial electrospinning films loaded with natural plant preservatives, namely laurel essential oil (LEO) and clove essential oil (CEO), were prepared by the coaxial electrospinning method synergistic with nanoemulsion techniques, and the hydrophilic preservation pads were prepared. The morphology of the film fiber is clear, without beads or damage, with fiber diameters falling within the 230-260 nm range. It has a distinct core-shell structure, exceptional thermal stability, and strong antibacterial and antioxidant properties. The core-shell structure of the fiber subtly regulates the release of preservatives and significantly improves the utilization efficiency. At the same time, the synergistic use of two essential oils can reduce the amount while amplifying their effectiveness. The pads significantly slowed down the increase of key indicators of spoilage, such as total viable count (TVC), pH, thiobarbituric acid reactive substances (TBA), and total volatile base nitrogen (TVB-N), during the storage of the fish fillets. Furthermore, the pads effectively slowed down the decline in water-holding capacity, the deterioration of textural qualities, and the negative changes in the microstructure of the fish muscle. Ultimately, the pads notably delayed the spoilage of fish fillets, extending their shelf life from 5 d to 9 d. The efficient utilization of biological preservatives in this film can provide technical support for the development of food preservation materials.

Advances in Electrospun Nanofiber Membranes for Dermatological Applications: A Review

In recent years, a wide variety of high-performance and versatile nanofiber membranes have been successfully created using different electrospinning methods. As vehicles for medication, they have been receiving more attention because of their exceptional antibacterial characteristics and ability to heal wounds, resulting in improved drug delivery and release. This quality makes them an appealing choice for treating various skin conditions like wounds, fungal infections, skin discoloration disorders, dermatitis, and skin cancer. This article offers comprehensive information on the electrospinning procedure, the categorization of nanofiber membranes, and their use in dermatology. Additionally, it delves into successful case studies, showcasing the utilization of nanofiber membranes in the field of skin diseases to promote their substantial advancement.

Metal-phenolic networks spontaneously reinforced carrageenan-based packaging films with antibacterial and antioxidant properties

The burdens of microbial food safety and environmental contamination make it necessary to search sustainable, safe, antibacterial and antioxidant active food packaging materials. This contribution proposed the use of copper-ferulic acid networks (CuFA NWs) as antibacterial substances. By immobilizing CuFA NWs into carrageenan matrix, a CuFA network-reinforced carrageenan-based packaging film (Carr/CuFA) was obtained via spontaneously hydrogen bond and electrostatic interaction indicated by ATR-IR and XPS. Interestingly, the addition of CuFA NWs increased the mechanical strength, surface hydrophobicity, and water vapor barrier properties of the carrageenan-based film, and imparted the film with UV-shielding capacity. Importantly, the Carr/CuFAx film exhibited effective antioxidant activity, and antibacterial performance against four foodborne bacteria. As a result, after confirming the safety of Carr/CuFA3 films by releasing, hemolysis and cell viability experiments, the Carr/CuFA3 film exhibited great potential in the safety control and preservation of fresh fruit by using blueberry and cherry as model fruit. In summary, this work provides a feasible candidate for the preservation and contamination control of fresh fruit.

Application and Development of Electrospun Nanofiber Scaffolds for Bone Tissue Engineering

Nanofiber scaffolds have gained significant attention in the field of bone tissue engineering. Electrospinning, a straightforward and efficient technique for producing nanofibers, has been extensively researched. When used in bone tissue engineering scaffolds, electrospun nanofibers with suitable surface properties promote new bone tissue growth and enhance cell adhesion. Recent advancements in electrospinning technology have provided innovative approaches for scaffold fabrication in bone tissue engineering. This review comprehensively examines the utilization of electrospun nanofibers in bone tissue engineering scaffolds and evaluates the relevant literature. The review begins by presenting the fundamental principles and methodologies of electrospinning. It then discusses various materials used in the production of electrospun nanofiber scaffolds for bone tissue engineering, including natural and synthetic polymers, as well as certain inorganic materials. The challenges associated with these materials are also described. The review focuses on novel electrospinning techniques for scaffold construction in bone tissue engineering, such as multilayer nanofibers, multifluid electrospinning, and the integration of electrospinning with other methods. Recent advancements in electrospinning technology have enabled the fabrication of precisely aligned nanofiber scaffolds with nanoscale architectures. These innovative methods also facilitate the fabrication of biomimetic structures, wherein bioactive substances can be incorporated and released in a controlled manner for drug delivery purposes. Moreover, they address issues encountered with traditional electrospun nanofibers, such as mechanical characteristics and biocompatibility. Consequently, the development and implementation of novel electrospinning technologies have revolutionized scaffold fabrication for bone tissue engineering.

Preparation of poly(vinyl alcohol) nanofibers containing disulfiram-copper complex by electrospinning: a potential delivery system against melanoma

BACKGROUND

Melanoma poses a significant threat to human health, making the development of a safe and effective treatment a crucial challenge. Disulfiram (DS) is a proven anticancer drug that has shown effectiveness when used in combination with copper (DS-Cu complex).

OBJECTIVES

This study focuses on encapsulation of DS-copper complex into nanofiber scaffold from polyvinyl alcohol (PVA) (DS-Cu@PVA). In order to increase bioavailability towards melanoma cell lines and decrease its toxicity.

METHODS

The scaffold was fabricated through an electrospinning process using an aqueous solution, and subsequently analyzed using ART-Fourier transform infrared spectroscopy (ART-FTIR), scanning electron microscopy (SEM), and energy dispersive X-ray analysis (EDX). Additionally, cellular cytotoxicity, flow cytometry analysis, and determination of caspase 3 activity were conducted to further characterize the scaffold.

RESULTS

The results confirmed that encapsulation of DS-Cu complex into PVA was successful via different characterization. The scanning electron microscopy (SEM) analysis revealed that the diameter of the nanofibers remained consistent despite the addition of DS-Cu. Additionally, ATR-FTIR confirmed that the incorporation of DS-Cu into PVA did not significantly alter the characteristic peaks of PVA. Furthermore, the cytotoxicity assessment of the DS-Cu@PVA nanofibrous scaffold using human normal skin cells (HFB4) demonstrated its superior biocompatibility compared to DS-Cu-free counterparts. Notably, the presence of DS-Cu maintained its effectiveness in promoting apoptosis by increasing cellular reactive oxygen species, proapoptotic gene expression, and caspase 3 activity, while simultaneously reducing glutathione levels and oncogene expression in human and mouse melanoma cell lines (A375 and B16F10, respectively). Overall, these findings suggest that the addition of DS-Cu to PVA nanofibers enhances their biocompatibility and cytotoxic effects on melanoma cells, making them a promising candidate for biomedical applications.

CONCLUSION

The findings indicate that the targeted delivery of DS-Cu onto a PVA nanofiber scaffold holds potential approach to enhance the efficacy of DS-Cu in combating melanoma.

Alginate-Based Electrospun Nanofibers and the Enabled Drug Controlled Release Profiles: A Review

Alginate is a natural polymer with good biocompatible properties and is a potential polymeric material for the sustainable development and replacement of petroleum derivatives. However, the non-spinnability of pure alginate solutions has hindered the expansion of alginate applications. With the continuous development of electrospinning technology, synthetic polymers, such as PEO and PVA, are used as co-spinning agents to increase the spinnability of alginate. Moreover, the coaxial, parallel Janus, tertiary and other diverse and novel electrospun fiber structures prepared by multi-fluid electrospinning have found a new breakthrough for the problem of poor spinning of natural polymers. Meanwhile, the diverse electrospun fiber structures effectively achieve multiple release modes of drugs. The powerful combination of alginate and electrostatic spinning is widely used in many biomedical fields, such as tissue engineering, regenerative engineering, bioscaffolds, and drug delivery, and the research fever continues to climb. This is particularly true for the controlled delivery aspect of drugs. This review provides a brief overview of alginate, introduces new advances in electrostatic spinning, and highlights the research progress of alginate-based electrospun nanofibers in achieving various controlled release modes, such as pulsed release, sustained release, biphasic release, responsive release, and targeted release.

Hybrid films loaded with 5-fluorouracil and Reglan for synergistic treatment of colon cancer via asynchronous dual-drug delivery

Combination therapy with oral administration of several active ingredients is a popular clinical treatment for cancer. However, the traditional method has poor convenience, less safety, and low efficiency for patients. The combination of traditional pharmaceutical techniques and advanced material conversion methods can provide new solutions to this issue. In this research, a new kind of hybrid film was created via coaxial electrospraying, followed by a casting process. The films were composed of Reglan and 5-fluorouracil (5-FU)-loaded cellulose acetate (CA) core-shell particles in a polyvinylpyrrolidone (PVP) film matrix. Microscopic observations of these films demonstrated a solid cross section loaded with core-shell particles. X-ray diffraction and Fourier-transform infrared tests verified that the Reglan and 5-FU loaded in the films showed amorphous states and fine compatibilities with the polymeric matrices, i.e., PVP and CA, respectively. In vitro dissolution tests indicated that the films were able to provide the desired asynchronous dual-drug delivery, fast release of Reglan, and sustained release of 5-FU. The controlled release mechanisms were shown to be an erosion mechanism for Reglan and a typical Fickian diffusion mechanism for 5-FU. The protocols reported herein pioneer a new approach for fabricating biomaterials loaded with multiple drugs, each with its own controlled release behavior, for synergistic cancer treatment.

Integrated Janus nanofibers enabled by a co-shell solvent for enhancing icariin delivery efficiency

During the past several decades, nanostructures have played their increasing influences on the developments of novel nano drug delivery systems, among which, double-chamber Janus nanostructure is a popular one. In this study, a new tri-channel spinneret was developed, in which two parallel metal capillaries were nested into another metal capillary in a core-shell manner. A tri-fluid electrospinning was conducted with a solvent mixture as the shell working fluid for ensuring the formation of an integrated Janus nanostructure. The scanning electronic microscopic results demonstrated that the resultant nanofibers had a linear morphology and two distinct compartments within them, as indicated by the image of a cross-section. Fourier Transformation Infra-Red spectra and X-Ray Diffraction patterns verified that the loaded poorly water-soluble drug, i.e. icariin, presented in the Janus medicated nanofibers in an amorphous state, which should be attributed to the favorable secondary interactions between icariin and the two soluble polymeric matrices, i.e. hydroxypropyl methyl cellulose (HPMC) and polyvinylpyrrolidone (PVP). The in vitro dissolution tests revealed that icariin, when encapsulated within the Janus nanofibers, exhibited complete release within a duration of 5 min, which was over 11 times faster compared to the raw drug particles. Furthermore, the ex vivo permeation tests demonstrated that the permeation rate of icariin was 16.2 times higher than that of the drug powders. This improvement was attributed to both the rapid dissolution of the drug and the pre-release of the trans-membrane enhancer sodium lauryl sulfate from the PVP side of the nanofibers. Mechanisms for microformation, drug release, and permeation were proposed. Based on the methodologies outlined in this study, numerous novel Janus nanostructure-based nano drug delivery systems can be developed for poorly water-soluble drugs in the future.

Electrospun radially oriented berberine-PHBV nanofiber dressing patches for accelerating diabetic wound healing

A dressing patch made of radially oriented poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanofibers was successfully manufactured with a modified electrospinning strategy. The as-electrospun PHBV radially oriented nanofiber dressing patch exhibited uniform and bead-free nanofibrous morphology and innovative radially oriented arrangement, which was demonstrated to possess obviously improved mechanical property, increased surface hydrophilicity and enhanced biological properties compared to the PHBV nanofiber dressing patch control with traditionally randomly oriented pattern. Interestingly, it was found that the radially oriented pattern could induce the cell migration from the periphery to the center along the radially oriented nanofibers in a rapid manner. To further improve the biofunction of PHBV radially oriented nanofiber dressing patch, berberine (Beri, an isoquinoline alkaloid) with two different concentrations were encapsulated into PHBV nanofibers during electrospinning, which were found to present a sustained drug release behavior for nearly one month. Importantly, the addition of Beri could impart the dressing patch with excellent anti-inflammatory property by significantly inhibiting the secretion of pro-inflammatory factors of M1 macrophages, and also showed an additive influence on promoting the proliferation of human dermal fibroblasts (HDFs), as well as inhibiting the growth of E. coli, S. aureus and C. albicans, compared with the Beri-free dressing patch. In the animal studies, the electrospun PHBV radially oriented nanofiber dressing patch loading with high Beri content was found to obviously accelerate the healing process of diabetic mouse full-thickness skin wound with shortened healing time (100% wound closure rate after 18 days' treatment) and improved healing quality (improved collagen deposition, enhanced re-epithelialization and neovascularization and increased hair follicles). In all, this study reported an innovative therapeutic strategy integrating the excellent physical cues of electrospun PHBV radially oriented nanofiber dressing patch with the multiple biological cues of Beri for the effective treatment of hard-to-heal diabetic wounds.

Electrospun medicated gelatin/polycaprolactone Janus fibers for photothermal-chem combined therapy of liver cancer

Liver cancer is a common cancer in the world, and core-shell nanoparticles as a commonly used combination therapy for local tumor ablation, have many shortcomings. In this study, photothermal Janus nanofibers were prepared using a electrospinning technology for tumor treatment, and the products were characterized and in vitro photothermal performance investigated. The micromorphology analysis showed that the photothermic agent CuS and electrospun fibers (loaded with CuS and anticancer drug dihydromyricetin) were successfully prepared, with diameters of 11.58 ± 0.27 μm and 1.19 ± 0.01 μm, respectively. Water contact angle and tensile test indicated that the fiber membranes has a certain hydrophilic adhesion and excellent mechanical strength. The fiber membranes has 808 nm near-infrared laser photothermal heating performance and photothermal stability, and it also has a strong response to the laser that penetrates biological tissue. In addition, in vitro cell culture and in vivo implantation study showed that the fiber membranes could kill HepG2 hepatocellular carcinoma cells combined with photothermal-chem and could be enriched in the implantation area, respectively. Hence, the Janus membranes may be a potential cancer treatment material.

Flame spray pyrolyzed carbon-encapsulated Au/Fe3O4 nanoaggregates enabled efficient photothermal therapy and magnetic hyperthermia of esophageal cancer cells

Multifunctional magneto-plasmonic nanoparticles with magnetic hyperthermia and photothermal therapy could kill cancer cells efficiently. Herein, carbon-encapsulated Au/Fe3O4 (Au/Fe3O4@C) was fabricated using an enclosed flame spray pyrolysis. The nanostructures, including an Fe3O4 core (51.9-55.2 nm) with a decreasing carbon shell thickness and an Au core (4.68-8.75 nm) coated with 2-4 graphite layers, were tailored by tuning the C2H4 content in the reacting gas mixture. Saturation magnetization (33.7-48.2 emu/g) and optical absorption were determined. The carbon shell facilitated the dispersion of Au/Fe3O4 and restrained their laser-induced and magnetic field-induced coalescence and growth. Au/Fe3O4@C exhibited excellent magnetic resonance imaging capability (91.4 mM-1 s-1) and photothermal performance (65.4°C for 0.8 mg/mL Au/Fe3O4@C at a power density of 1.0 W/cm2 after 300 s near-IR laser irradiation (808 nm)). Moreover, the combined application of photothermal and magnetic-heating properties reduced the required intensity of both laser and magnetic field compared to the intensity of separate situations. Our work provides a unique, intriguing approach to preparing multicomponent core/shell nanoaggregates that are promising candidates for esophageal cancer cell therapy.

Electrosprayed Eudragit RL100 nanoparticles with Janus polyvinylpyrrolidone patches for multiphase release of paracetamol

Advanced nanotechniques and the corresponding complex nanostructures they produce represent some of the most powerful tools for developing novel drug delivery systems (DDSs). In this study, a side-by-side electrospraying process was developed for creating double-chamber nanoparticles in which Janus soluble polyvinylpyrrolidone (PVP) patches were added to the sides of Eudragit RL100 (RL100) particles. Both sides were loaded with the poorly water-soluble drug paracetamol (PAR). Scanning electron microscope results demonstrated that the electrosprayed nanoparticles had an integrated Janus nanostructure. Combined with observations of the working processes, the microformation mechanism for creating the Janus PVP patches was proposed. XRD, DSC, and ATR-FTIR experiments verified that the PAR drug was present in the Janus particles in an amorphous state due to its fine compatibility with the polymeric matrices. In vitro dissolution tests verified that the Janus nanoparticles were able to provide a typical biphasic drug release profile, with the PVP patches providing 43.8 ± 5.4% drug release in the first phase in a pulsatile manner. In vivo animal experiments indicated that the Janus particles, on one hand, could provide a faster therapeutic effect than the electrosprayed sustained-release RL100 nanoparticles. On the other hand, they could maintain a therapeutic blood drug concentration for a longer period. The controlled release mechanism of the drug was proposed. The protocols reported here pioneer a new process-structure-performance relationship for developing Janus-structure-based advanced nano-DDSs.

Development and evaluation of sildenafil/glycyrrhizin-loaded nanofibers as a potential novel buccal delivery system for erectile dysfunction

Erectile dysfunction (ED) is a growing health condition that needs safe and effective therapy. One of the main common treatments is sildenafil which is used in clinics for managing erectile dysfunction by enhancing the blood supply to the penis. In the current study, sildenafil was formulated as nanofibers and mixed with the root extract of Glycyrrhiza glabra (glycyrrhizin) as a natural sweetener to be administrated in the buccal cavity for enhanced drug bioavailability, rapid drug absorption and improved patient compliance. The formulated dual-loaded nanofibers were evaluated by measuring diameter, disintegration, drug loading efficiency, drug release profile, and in vitro cell viability assessment. The results showed that the sildenafil/glycyrrhizin-loaded fibers had a diameter of 0.719 ± 0.177 μm and lacked any beads and pores formation on their surfaces. The drug loading and encapsulation efficiency for sildenafil were measured as 52 ± 7 µg/mg and 67 ± 9 %, respectively, while they were 290 ± 32 μg/mg and 94 ± 10 %, respectively, for glycyrrhizin. The release rate of sildenafil and glycyrrhizin demonstrated a burst release in the first minute, followed by a gradual increment until a complete release after 120 min. The in vitro cell viability evaluation exhibited that the application of sildenafil and glycyrrhizin is safe upon 24-hour treatment on human skin fibroblast cells at all used concentrations (i.e., ≤ 1,000 and 4,000 μg/mL, respectively). However, the application of sildenafil-glycyrrhizin combination (in a ratio of 1:4) demonstrated more than 80 % cell viability at concentrations of ≤ 250 and 1000 μg/mL, respectively, following 24-hour cell exposure. Therefore, sildenafil/glycyrrhizin dual-loaded PVP nanofibers showed a potential buccal therapeutic approach for erectile dysfunction management.

Engineered shapes using electrohydrodynamic atomization for an improved drug delivery

The shapes of micro- and nano-products have profound influences on their functional performances, which has not received sufficient attention during the past several decades. Electrohydrodynamic atomization (EHDA) techniques, mainly include electrospinning and electrospraying, are facile in manipulate their products' shapes. In this review, the shapes generated using EHDA for modifying drug release profiles are reviewed. These shapes include linear nanofibers, round micro-/nano-particles, and beads-on-a-string hybrids. They can be further divided into different kinds of sub-shapes, and can be explored for providing the desired pulsatile release, sustained release, biphasic release, delayed release, and pH-sensitive release. Additionally, the shapes resulted from the organizations of electrospun nanofibers are discussed for drug delivery, and the shapes and inner structures can be considered together for developing novel drug delivery systems. In future, the shapes and the related shape-performance relationships at nanoscale, besides the size, inner structure and the related structure-performance relationships, would further play their important roles in promoting the further developments of drug delivery field. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies.

Accelerated Wound Healing by Electrospun Multifunctional Fibers with Self-Powered Performance

Wound healing has been a persistent clinical challenge for a long time. Electrical stimulation is an effective therapy with the potential to accelerate wound healing. In this work, the self-powered electrospun nanofiber membranes (triples) were constructed as multifunctional wound dressings with electrical stimulation and biochemical capabilities. Triple was composed of a hydrolyzable inner layer with antiseptic and hemostatic chitosan, a hydrophilic core layer loaded with conductive AgNWs, and a hydrophobic outer layer fabricated by self-powered PVDF. Triple exhibited presentable wettability and acceptable moisture permeability. Electrical performance tests indicated that triple can transmit electrical signals formed by the piezoelectric effect to the wound. High antibacterial activities were observed for triple against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, with inhibition rates of 96.52, 98.63, and 97.26%, respectively. In vitro cell assays demonstrated that triple cells showed satisfactory proliferation and mobility. A whole blood clotting test showed that triple can enhance hemostasis. The innovative self-powered multifunctional fibers presented in this work offer a promising approach to addressing complications and expediting the promotion of chronic wound healing.

Recent progress of electrospun nanofibers as burning dressings

Burns are a global public health problem, which brings great challenges to public health and the economy. Severe burns often lead to systemic infection, shock, multiple organ failure, and even death. With the increasing demand for the therapeutic effect of burn wounds, traditional dressings have been unable to meet people's needs due to their single function and many side effects. In this context, electrospinning shows a great prospect on the way to open up advanced wound dressings that promote wound repairing and prevent infection. With its large specific surface area, high porosity, and similar to natural extracellular matrix (ECM), electrospun nanofibers can load drugs and accelerate wound healing. It provides a promising solution for the treatment and management of burn wounds. This review article introduces the concept of burn and the types of electrospun nanofibers, then summarizes the polymers used in electrospun nanofiber dressings. Finally, the drugs (plant extracts, small molecule drugs and nanoparticles) loaded with electrospun burn dressings are summarized. Some promising aspects for developing commercial electrospun burn dressings are proposed.

Hydrophilic and hydrophobic drug release from core (polyvinylpyrrolidone)-sheath (ethyl cellulose) pressure-spun fibers

A core-sheath structure is one of the methods developed to overcome the challenges often faced when using monolithic fibers for drug delivery. In this study, fibers based on polyvinylpyrrolidone (core) and ethyl cellulose (sheath) were successfully produced using a novel core-sheath pressure-spinning process. For comparison, these two polymers were also processed into as blend fibers. All samples were then investigated for their performances in releasing water-soluble ampicillin (AMP) and poorly water-soluble ibuprofen (IBU) model drugs. Scanning electron,digital and confocal microscopy confirmed that fibers with a core-sheath structure were successfully made. Fourier transform infrared spectroscopy showed the success of the pressure-spinning technique in encapsulating AMP/IBU in all fiber samples. Compared to blend fibers, the core-sheath fibers had better performance in encapsulating both water-soluble and poorly water-soluble drugs. Moreover, the core-sheath structure was able to reduce the initial burst release and provided a better sustained release profile than the blend fiber analog. In conclusion, the pressure-spinning method was capable of producing core-sheath and blend fibers that could be used for the loading of either hydrophilic or hydrophobic drugs for controlled drug delivery systems.

Electrospun Fenoprofen/Polycaprolactone @ Tranexamic Acid/Hydroxyapatite Nanofibers as Orthopedic Hemostasis Dressings

Dressings with multiple functional performances (such as hemostasis, promoting regeneration, analgesia, and anti-inflammatory effects) are highly desired in orthopedic surgery. Herein, several new kinds of medicated nanofibers loaded with several active ingredients for providing multiple functions were prepared using the modified coaxial electrospinning processes. With an electrospinnable solution composed of polycaprolactone and fenoprofen as the core working fluid, several different types of unspinnable fluids (including pure solvent, nanosuspension containing tranexamic acid and hydroxyapatite, and dilute polymeric solution comprising tranexamic acid, hydroxyapatite, and polyvinylpyrrolidone) were explored to implement the modified coaxial processes for creating the multifunctional nanofibers. Their morphologies and inner structures were assessed through scanning and transmission electron microscopes, which all showed a linear format without the discerned beads or spindles and a diameter smaller than 1.0 μm, and some of them had incomplete core-shell nanostructures, represented by the symbol @. Additionally, strange details about the sheaths' topographies were observed, which included cracks, adhesions, and embedded nanoparticles. XRD and FTIR verified that the drugs tranexamic acid and fenoprofen presented in the nanofibers in an amorphous state, which resulted from the fine compatibility among the involved components. All the prepared samples were demonstrated to have a fine hydrophilic property and exhibited a lower water contact angle smaller than 40° in 300 ms. In vitro dissolution tests indicated that fenoprofen was released in a sustained manner over 6 h through a typical Fickian diffusion mechanism. Hemostatic tests verified that the intentional distribution of tranexamic acid on the shell sections was able to endow a rapid hemostatic effect within 60 s.

Electrospun L-Lysine/Amorphous Calcium Phosphate Loaded Core-Sheath Nanofibers for Managing Oral Biofilm Infections and Promoting Periodontal Tissue Repairment

Introduction

Periodontitis, a chronic inflammatory disease prevalent worldwide, is primarily treated through GTR for tissue regeneration. The efficacy of GTR, however, remains uncertain due to potential infections and the intricate microenvironment of periodontal tissue. Herein, We developed a novel core-shell structure multifunctional membrane using a dual-drug-loaded coaxial electrospinning technique (Lys/ACP-CNF), contains L-lysine in the outer layer to aid in controlling biofilms after GTR regenerative surgery, and ACP in the inner layer to enhance osteogenic performance for accelerating alveolar bone repair.

Methods

The biocompatibility and cell adhesion were evaluated through CCK-8 and fluorescence imaging, respectively. The antibacterial activity was assessed using a plate counting assay. ALP, ARS, and RT-qPCR were used to examine osteogenic differentiation. Additionally, an in vivo experiment was conducted on a rat model with acute periodontal defect and infection. Micro-CT and histological analysis were utilized to analyze the in vivo alveolar bone regeneration.

Results

Structural and physicochemical characterization confirmed the successful construction of the core-shell fibrous structure. Additionally, the Lys/ACP-CNF showed strong antibacterial coaggregation effects and induced osteogenic differentiation of PDLSCs in vitro. The in vivo experiment confirmed that Lys/ACP-CNF promotes new bone formation.

Conclusion

Lys/ACP-CNF rapidly exhibited excellent antibacterial activity, protected PDLSCs from infection, and was conducive to osteogenesis, demonstrating its potential application for clinical periodontal GTR surgery.

Recent advances of electrospray technique for multiparticulate preparation: Drug delivery applications

The electrospray (ES) technique has proven to be an effective and a versatile approach for crafting drug delivery carriers with diverse dimensions, multiple layers, and varying morphologies. Achieving the desired particle properties necessitates careful optimization of various experimental parameters. This review delves into the most prevalent ES system configurations employed for this purpose, such as monoaxial, coaxial, triaxial, and multi-needle setups with solid or liquid collector. In addition, this work underscores the significance of ES in drug delivery carriers and its remarkable ability to encapsulate a wide spectrum of therapeutic agents, including drugs, nucleic acids, proteins, genes and cells. Depth examination of the critical parameters governing the ES process, including the choice of polymer, surface tension, voltage settings, needle size, flow rate, collector types, and the collector distance was conducted with highlighting on their implications on particle characteristics, encompassing morphology, size distribution, and drug encapsulation efficiency. These insights illuminate ES's adaptability in customizing drug delivery systems. To conclude, this review discusses ES process optimization strategies, advantages, limitations and future directions, providing valuable guidance for researchers and practitioners navigating the dynamic landscape of modern drug delivery systems.

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.

Ferulic acid's therapeutic odyssey: nano formulations, pre-clinical investigations, and patent perspective

INTRODUCTION

Ferulic acid (FA) is a phenolic phytochemical that has garnered the attention of the research community due to its abundant availability in nature. It is a compound that has been explored for its multifaceted therapeutic potential and benefits in modern and contemporary healthcare.

AREAS COVERED

This review furnishes a compilation of the molecular mechanisms underlying the anti-diabetic, anticancer, antioxidant, and anti-inflammatory effects of FA. We also aim to excavate an in-depth analysis of the role of nanoformulations to achieve release control, reduce toxicity, and deliver FA at specified target sites. To corroborate the safety and efficacy of FA, a multitude of pre-clinical studies have also been conducted by researchers and have been discussed comprehensively in this review. The various patented innovations and newer paradigms pertaining to FA have also been presented.

EXPERT OPINION

Enormous research has been conducted and should still be continued to find the best possible novel drug delivery system for FA delivery. The utilization of nanocarriers and nanoformulations has intrigued the scientists for delivery of FA, but before that, it is necessary to shed light upon toxicity, safety, and regulatory concerns of FA.

Smart Nanofibrous Hydrogel Wound Dressings for Dynamic Infection Diagnosis and Control: Soft but Functionally Rigid

Chronic wounds, such as burns and diabetic foot ulcers, pose significant challenges to global healthcare systems due to prolonged hospitalization and increased costs attributed to susceptibility to bacterial infections. The conventional use of antibiotic-loaded and metal-impregnated dressings exacerbates concerns related to multidrug resistance and skin argyrosis. In response to these challenges, our research introduces a unique approach utilizing antibiotic-free smart hydrogel wound dressings with integrated infection eradication and diagnostic capabilities. Electrospinning stands out as a method capable of producing hydrogel nanofibrous materials possessing favorable characteristics for treating wounds and detecting infections under conditions utilizing sustainable materials. In this study, innovative dressings are fabricated through electrospinning polycaprolactone (PCL)/gelatin (GEL) hybrid hydrogel nanofibers, incorporating pDA as a cross-linker, εPL as a broad-spectrum antimicrobial agent, and anthocyanin as a pH-responsive probe. The developed dressings demonstrate exceptional antioxidant (>90% radical scavenging) and antimicrobial properties (95-100% killing). The inclusion of polyphenols/flavonoids and εPL leads to absolute bacterial eradication, and in vitro assessments using HaCaT cells indicate increased cell proliferation, decreased reactive oxygen species (ROS) production, and enhanced cell viability (100% Cell viability). The dressings display notable alterations in color that correspond to different wound conditions. Specifically, they exhibit a red/violet hue under healthy wound conditions (pH 4-6.5) and a green/blue color under unhealthy wound conditions (pH > 6.5). These distinctive color changes provide valuable insights into the versatile applications of the dressings in the care and management of wounds. Our findings suggest that these antibiotic-free smart hydrogel wound dressings hold promise as an effective and sustainable solution for chronic wounds, providing simultaneous infection control and diagnostic monitoring. This research contributes to advancing the field of wound care, offering a potential paradigm shift in the development of next-generation wound dressings.

Research Advances in Superabsorbent Polymers

Superabsorbent polymers are new functional polymeric materials that can absorb and retain liquids thousands of times their masses. This paper reviews the synthesis and modification methods of different superabsorbent polymers, summarizes the processing methods for different forms of superabsorbent polymers, and organizes the applications and research progress of superabsorbent polymers in industrial, agricultural, and biomedical industries. Synthetic polymers like polyacrylic acid, polyacrylamide, polyacrylonitrile, and polyvinyl alcohol exhibit superior water absorption properties compared to natural polymers such as cellulose, chitosan, and starch, but they also do not degrade easily. Consequently, it is often necessary to modify synthetic polymers or graft superabsorbent functional groups onto natural polymers, and then crosslink them to balance the properties of material. Compared to the widely used superabsorbent nanoparticles, research on superabsorbent fibers and gels is on the rise, and they are particularly notable in biomedical fields like drug delivery, wound dressing, and tissue engineering.

Enhancing diabetic wound healing: advances in electrospun scaffolds from pathogenesis to therapeutic applications

Diabetic wounds are a significant subset of chronic wounds characterized by elevated levels of inflammatory cytokines, matrix metalloproteinases (MMPs), and reactive oxygen species (ROS). They are also associated with impaired angiogenesis, persistent infection, and a high likelihood of hospitalization, leading to a substantial economic burden for patients. In severe cases, amputation or even mortality may occur. Diabetic foot ulcers (DFUs) are a common complication of diabetes, with up to 25% of diabetic patients being at risk of developing foot ulcers over their lifetime, and more than 70% ultimately requiring amputation. Electrospun scaffolds exhibit a structural similarity to the extracellular matrix (ECM), promoting the adhesion, growth, and migration of fibroblasts, thereby facilitating the formation of new skin tissue at the wound site. The composition and size of electrospun scaffolds can be easily adjusted, enabling controlled drug release through fiber structure modifications. The porous nature of these scaffolds facilitates gas exchange and the absorption of wound exudate. Furthermore, the fiber surface can be readily modified to impart specific functionalities, making electrospinning nanofiber scaffolds highly promising for the treatment of diabetic wounds. This article provides a concise overview of the healing process in normal wounds and the pathological mechanisms underlying diabetic wounds, including complications such as diabetic foot ulcers. It also explores the advantages of electrospinning nanofiber scaffolds in diabetic wound treatment. Additionally, it summarizes findings from various studies on the use of different types of nanofiber scaffolds for diabetic wounds and reviews methods of drug loading onto nanofiber scaffolds. These advancements broaden the horizon for effectively treating diabetic wounds.

Apricot polysaccharides as new carriers to make curcumin nanoparticles and improve its stability and antibacterial activity

Apricot polysaccharides (APs) as new types of natural carriers for encapsulating and delivering active pharmaceutical ingredients can achieve high-value utilization of apricot pulp and improve the solubility, the stability, and the antibacterial activity of insoluble compounds simultaneously. In this research, the purified APs reacted with bovine serum albumin (BSA) by the Maillard reaction, and with d-α-tocopheryl succinate (TOS) and pheophorbide A (PheoA) by grafting to fabricate two materials for the preparation of curcumin (Cur)-encapsulated AP-BSA nanoparticles (CABNs) and Cur-embedded TOS-AP-PheoA micelles (CTAPMs), respectively. The biological activities of two Cur nano-delivery systems were evaluated. APs consisted of arabinose (22.36%), galactose (7.88%), glucose (34.46%), and galacturonic acid (31.32%) after the optimized extraction. Transmission electron microscopy characterization of CABNs and CTAPMs displayed a discrete and non-aggregated morphology with a spherical shape. Compared to the unencapsulated Cur, the release rates of CABNs and CTAPMs decreased from 87% to 70% at 3 h and from 92% to 25% at 48 h, respectively. The antioxidant capacities of CABNs and CTAPMs were significantly improved. The CTAPMs exhibited a better antibacterial effect against Escherichia coli than CABNs due to the synergistic photosensitive effect between Cur and PheoA.

Impact Evaluations of Articles in Current Drug Delivery based on Web of Science

A total of 1534 and 308 articles were published in the journal Current Drug Delivery (CDD), from 2004 and 2019 to 2021, respectively. In this commentary, their impacts were analyzed based on search data about citation times in the Web of Science. These publications were categorized from different standpoints and evaluated in terms of their citations, particularly in the year 2021. The thematic, contemporary, and local features of these articles, as well as the article types and publication formats, were interpreted. Results demonstrated that CDD should be loyal to the contents about drug delivery, particularly nano-drug delivery systems and nano-pharmaceutical technologies. Publications from the developing and developed countries and regions showed no remarkable differences; therefore, submissions are similarly welcomed. Research articles and review articles are the main stream of CDD. The ratio of review papers is about 30%, which is reasonable but should not be further extended. Moreover, open publications with an article processing charge always have a high impact than those with subscription.

Electrospun Core-Sheath Nanofibers with a Cellulose Acetate Coating for the Synergistic Release of Zinc Ion and Drugs

Precisely modulating the synergistic release behavior of multiple bioactive substances has emerged as a formidable challenge in recent years. In this work, we successfully prepared core-sheath nanofibers, where a thin cellulose acetate (CA) coating enrobed the core. Curcumin (Cur) was encapsulated in the core layer as a model drug, while zinc oxide (ZnO) nanoparticles were loaded on the sheath layer. The prepared fiber exhibited a straight cylindrical morphology containing nanoparticles, and the distinct core-sheath nanostructure was demonstrated through transmission electron microscopy (TEM). X-ray diffraction (XRD) and Fourier transform infrared (FTIR) were conducted to study the physical state and compatibility among CA, Cur, and ZnO. Drug release data indicated that core-sheath nanofibers were able to decelerate the rate of drug release, and the thickness of the sheath layer increased in the presence of ZnO particles. Most remarkably, these core-sheath nanofibers exhibited the remarkable ability to sustain the release of drugs and zinc ion (Zn2+), the two-day synergistically release behavior leading to a significant increase in cell proliferation. This material preparation strategy for the synergistic and controlled release of two bioactive substances is instructive for the exploration of innovative and versatile drug delivery systems.

A combined electrohydrodynamic atomization method for preparing nanofiber/microparticle hybrid medicines

Bacterial prostatitis is a challenging condition to treat with traditional dosage forms. Physicians often prescribe a variety of dosage forms with different administration methods, which fail to provide an efficient and convenient mode of drug delivery. The aim of this work was to develop a new type of hybrid material incorporating both electrosprayed core-shell microparticles and electrospun nanofibers. A traditional Chinese medicine (Ningmitai, NMT) and a Western medicine (ciprofloxacin, CIP) were co-encapsulated within this material and were designed to be released in a separately controlled manner. Utilizing polyvinylpyrrolidone (PVP) as a hydrophilic filament-forming polymer and pH-sensitive Eudragit® S100 (ES100) as the particulate polymeric matrix, a combined electrohydrodynamic atomization (EHDA) method comprising coaxial electrospraying and blending electrospinning, was used to create the hybrids in a single-step and straightforward manner. A series of characterization methods were conducted to analyze both the working process and its final products. Scanning electron microscopy and transmission electron microscopy revealed that the EHDA hybrids comprised of both CIP-PVP nanofibers and NMT-ES100 core-shell microparticles. Multiple methods confirmed the rapid release of CIP and the sustained release of NMT. The antibacterial experiments indicated that the hybrids exhibited a more potent antibacterial effect against Escherichia coli dh5α and Bacillus subtilis Wb800 than either the separate nanofibers or microparticles. The amalgamation of fibrous nanomedicine and particulate micromedicine can expand the horizon of new types of medicines. The integration of electrospinning and coaxial electrospraying provides a straightforward approach to fabrication. By combining hydrophilic soluble polymers and pH-sensitive polymers in the hybrids, we can ensure the separate sequential controlled release of CIP and NMT for a potential synergistic and convenient therapy for bacterial prostatitis.

Strategies to fortify the nutritional values of polished rice by implanting selective traits from brown rice: A nutrigenomics-based approach

Whole-grain cereals are important components of a healthy diet. It reduces the risk of many deadly diseases like cardiovascular diseases, diabetes, cancer, etc. Brown rice is an example of whole grain food, which is highly nutritious due to the presence of various bioactive compounds (flavonoids, phenolics, vitamins, phytosterols, oils, etc.) associated with the rice bran layer of brown rice. White rice is devoid of the nutritious rice bran layer and thus lacks the bioactive compounds which are the major attractants of brown rice. Therefore, to confer health benefits to the public at large, the nutrigenomic potential of white rice may be improved by integrating the phytochemicals associated with the rice bran layer of brown rice into it via biofortification processes like conventional breeding, agronomic practices, metabolic engineering, CRISPR/Cas9 technology, and RNAi techniques. Thus, this review article focuses on improving the nutritional qualities of white/polished rice through biofortification processes, utilizing new breeding technologies (NBTs).

How can Electrospinning Further Service Well for Pharmaceutical Researches?

The past two decades have witnessed the enormous success and progress of electrospinning, as well as its broad and useful applications in pharmaceutics as a laboratory pharmaceutical nanotechnology. Everything in the past is a preface, in which the large screen opens for electrospinning and electrospun nanofibers (particularly those multiple-fluid electrospinning processes and the related multiple-chamber nanostructures) to stride into a new stage and the real commercial applications. In this commentary, four hot regions are identified for the further progress of the applications of electrospinning in pharmaceutics, in which electrospinning and its products can provide more and better services to the development of pharmaceutics.

Tri-Layer Core-Shell Fibers from Coaxial Electrospinning for a Modified Release of Metronidazole

Polymers are the backbone of drug delivery. Electrospinning has greatly enriched the strategies that have been explored for developing novel drug delivery systems using polymers during the past two decades. In this study, four different kinds of polymers, i.e., the water-soluble polymer poly (vinyl alcohol) (PVA), the insoluble polymer poly(ε-caprolactone) (PCL), the insoluble polymer Eudragit RL100 (ERL100) and the pH-sensitive polymer Eudragit S100 (ES100) were successfully converted into types of tri-layer tri-polymer core-shell fibers through bi-fluid coaxial electrospinning. During the coaxial process, the model drug metronidazole (MTD) was loaded into the shell working fluid, which was an emulsion. The micro-formation mechanism of the tri-layer core-shell fibers from the coaxial emulsion electrospinning was proposed. Scanning electron microscope and transmission electron microscope evaluations verified the linear morphology of the resultant fibers and their obvious tri-layer multiple-chamber structures. X-ray diffraction and Fourier transform infrared spectroscopy measurements demonstrated that the drug MTD presented in the fibers in an amorphous state and was compatible with the three polymeric matrices. In vitro dissolution tests verified that the three kinds of polymer could act in a synergistic manner for a prolonged sustained-release profile of MTD in the gut. The drug controlled-release mechanisms were suggested in detail. The protocols reported here pioneer a new route for creating a tri-layer core-shell structure from both aqueous and organic solvents, and a new strategy for developing advanced drug delivery systems with sophisticated drug controlled-release profiles.

Electrosprayed Core (Cellulose Acetate)-Shell (Polyvinylpyrrolidone) Nanoparticles for Smart Acetaminophen Delivery

Smart drug delivery, through which the drug molecules are delivered according to the requests of human biological rhythms or by maximizing drug therapeutic effects, is highly desired in pharmaceutics. Many biomacromolecules have been exploited for this application in the past few decades, both in industry and laboratories. Biphasic release, with an intentional pulsatile release and a following extended release stage, represents a typical smart drug delivery approach, which aims to provide fast therapeutic action and a long time period of effective blood drug concentration to the patients. In this study, based on the use of a well-known biomacromolecule, i.e., cellulose acetate (CA), as the drug (acetaminophen, ATP)-based sustained release carrier, a modified coaxial electrospraying process was developed to fabricate a new kind of core-shell nanoparticle. The nanoparticles were able to furnish a pulsatile release of ATP due to the shell polyvinylpyrrolidone (PVP). The time cost for a release of 30% was 0.32 h, whereas the core-shell particles were able to provide a 30.84-h sustained release of the 90% loaded ATP. The scanning electron microscope and transmission electron microscope results verified in terms of their round surface morphologies and the obvious core-shell double-chamber structures. ATP presented in both the core and shell sections in an amorphous state owing to its fine compatibility with CA and PVP. The controlled release mechanisms of ATP were suggested. The disclosed biomacromolecule-based process-structure-performance relationship can shed light on how to develop new sorts of advanced nano drug delivery systems.

Electrosprayed Stearic-Acid-Coated Ethylcellulose Microparticles for an Improved Sustained Release of Anticancer Drug

Sustained release is highly desired for "efficacious, safe and convenient" drug delivery, particularly for those anticancer drug molecules with toxicity. In this study, a modified coaxial electrospraying process was developed to coat a hydrophobic lipid, i.e., stearic acid (SA), on composites composed of the anticancer drug tamoxifen citrate (TC) and insoluble polymeric matrix ethylcellulose (EC). Compared with the electrosprayed TC-EC composite microparticles M1, the electrosprayed SA-coated hybrid microparticles M2 were able to provide an improved TC sustained-release profile. The 30% and 90% loaded drug sustained-release time periods were extended to 3.21 h and 19.43 h for M2, respectively, which were significantly longer than those provided by M1 (0.88 h and 9.98 h, respectively). The morphology, inner structure, physical state, and compatibility of the components of the particles M1 and M2 were disclosed through SEM, TEM, XRD, and FTIR. Based on the analyses, the drug sustained-release mechanism of multiple factors co-acting for microparticles M2 is suggested, which include the reasonable selections and organizations of lipid and polymeric excipient, the blank SA shell drug loading, the regularly round shape, and also the high density. The reported protocols pioneered a brand-new manner for developing sustained drug delivery hybrids through a combination of insoluble cellulose gels and lipid using modified coaxial electrospraying.

Direct jet coaxial electrospinning of axon-mimicking fibers for diffusion tensor imaging

Hollow polymer microfibers with variable microstructural and hydrophilic properties were proposed as building elements to create axon-mimicking phantoms for validation of diffusion tensor imaging (DTI). The axon-mimicking microfibers were fabricated in a mm-thick 3D anisotropic fiber strip, by direct jet coaxial electrospinning of PCL/polysiloxane-based surfactant (PSi) mixture as shell and polyethylene oxide (PEO) as core. Hydrophilic PCL-PSi fiber strips were first obtained by carefully selecting appropriate solvents for the core and appropriate fiber collector rotating and transverse speeds. The porous cross-section and anisotropic orientation of axon-mimicking fibers were then quantitatively evaluated using two ImageJ plugins-nearest distance (ND) and directionality based on their scanning electron microscopy (SEM) images. Third, axon-mimicking phantom was constructed from PCL-PSi fiber strips with variable porous-section and fiber orientation and tested on a 3T clinical MR scanner. The relationship between DTI measurements (mean diffusivity [MD] and fractional anisotropy [FA]) of phantom samples and their pore size and fiber orientation was investigated. Two key microstructural parameters of axon-mimicking phantoms including normalized pore distance and dispersion of fiber orientation could well interpret the variations in DTI measurements. Two PCL-PSi phantom samples made from different regions of the same fiber strips were found to have similar MD and FA values, indicating that the direct jet coaxial electrospun fiber strips had consistent microstructure. More importantly, the MD and FA values of the developed axon-mimicking phantoms were mostly in the biologically relevant range.

Integrating Chinese Herbs and Western Medicine for New Wound Dressings through Handheld Electrospinning

In this nanotechnology era, nanostructures play a crucial role in the investigation of novel functional nanomaterials. Complex nanostructures and their corresponding fabrication techniques provide powerful tools for the development of high-performance functional materials. In this study, advanced micro-nanomanufacturing technologies and composite micro-nanostructures were applied to the development of a new type of pharmaceutical formulation, aiming to achieve rapid hemostasis, pain relief, and antimicrobial properties. Briefly, an approach combining a electrohydrodynamic atomization (EHDA) technique and reversed-phase solvent was employed to fabricate a novel beaded nanofiber structure (BNS), consisting of micrometer-sized particles distributed on a nanoscale fiber matrix. Firstly, Zein-loaded Yunnan Baiyao (YB) particles were prepared using the solution electrospraying process. Subsequently, these particles were suspended in a co-solvent solution containing ciprofloxacin (CIP) and hydrophilic polymer polyvinylpyrrolidone (PVP) and electrospun into hybrid structural microfibers using a handheld electrospinning device, forming the EHDA product E3. The fiber-beaded composite morphology of E3 was confirmed through scanning electron microscopy (SEM) images. Fourier-transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) analysis revealed the amorphous state of CIP in the BNS membrane due to the good compatibility between CIP and PVP. The rapid dissolution experiment revealed that E3 exhibits fast disintegration properties and promotes the dissolution of CIP. Moreover, in vitro drug release study demonstrated the complete release of CIP within 1 min. Antibacterial assays showed a significant reduction in the number of adhered bacteria on the BNS, indicating excellent antibacterial performance. Compared with the traditional YB powders consisting of Chinese herbs, the BNS showed a series of advantages for potential wound dressing. These advantages include an improved antibacterial effect, a sustained release of active ingredients from YB, and a convenient wound covering application, which were resulted from the integration of Chinese herbs and Western medicine. This study provides valuable insights for the development of novel multiscale functional micro-/nano-composite materials and pioneers the developments of new types of medicines from the combination of herbal medicines and Western medicines.

Preparation and Characterization of Ferulic Acid Wheat Gluten Nanofiber Films with Excellent Antimicrobial Properties

In this study, composite nanofiber films comprising polyvinyl alcohol, wheat gluten, and glucose (PWG) were fabricated using electrospinning, followed by crosslinking via Maillard crosslinking. Various mass concentrations of ferulic acid (FA) were incorporated into PWG films. The results indicated that the average diameter of the FA-PWG films decreased from 449 nm to 331 nm as the concentration of FA increased, until reaching a concentration of 12%; after which, a significant increase in diameter was observed. The subsequent Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and differential scanning calorimetry (DSC) results suggested that FA was distributed in the sample films in an amorphous form through hydrogen and ester bonds. Additionally, release experiments and antimicrobial tests on the FA-PWG sample films showed the good controlled release of FA and excellent anti-Escherichia coli and Staphylococcus aureus activity of this film. These findings all indicate that the FA-PWG nanofiber film is a potential candidate for active food packaging.

Electrospun Biomolecule-Based Drug Delivery Systems

Drug delivery, mainly a professional term in pharmaceutics, is a field of interdisciplinary intersection and integration [...].

The Effects of Citric Acid Crosslinking on Fabrication and Characterization of Gelatin/Curcumin-Based Electrospun Antioxidant Nanofibers

Nanofibers, produced through the novel method of electrospinning, have a high ratio of surface area to volume, which allows them to have different optical, electrical, thermal, and mechanical properties than macroscale materials. In this study, it was aimed to produce nanofibers with gelatin and curcumin. The effects of gelatin concentration and crosslinking with citric acid on the characteristics of electrospun nanofibers were studied. Gelatin film containing neither citric acid nor curcumin was used as control. Solutions were evaluated by solution conductivity, color analysis, and rheological properties. Obtained nanofibers were characterized by morphological analysis (SEM), antioxidant activity (AA), thermal properties (TGA, XRD, DSC), water vapor permeability (WVP), and Fourier transform infrared (FTIR) analysis. It was found that the functional groups of gelatin were not changed significantly but some degree of crosslinking was seen, as indicated by the changes in AA, crystallinity, etc. Improvement in antioxidant activities was seen, which was the highest for gelatin and curcumin films (32%). The highest melting temperature (78 °C) and WVP (2.365 × 10^-10 gm^-1 s^-1 Pa^-1) was seen for gelatin and curcumin films crosslinked with 0.5% citric acid. Gelatin with curcumin films crosslinked with 1% citric acid showed the lowest crystallinity (1.56%). It was concluded that even though citric acid might not prove to be a stable crosslinking agent for the protein (gelatin), it contributed to the antioxidant nature of the films, along with curcumin. These films are promising candidates to be applied on cut fruits, to reduce water loss and oxidation and hence extend their shelf lives.

Dual-Step Controlled Release of Berberine Hydrochloride from the Trans-Scale Hybrids of Nanofibers and Microparticles

In this nano era, nanomaterials and nanostructures are popular in developing novel functional materials. However, the combinations of materials at micro and macro scales can open new routes for developing novel trans-scale products with improved or even new functional performances. In this work, a brand-new hybrid, containing both nanofibers and microparticles, was fabricated using a sequential electrohydrodynamic atomization (EHDA) process. Firstly, the microparticles loaded with drug (berberine hydrochloride, BH) molecules in the cellulose acetate (CA) were fabricated using a solution electrospraying process. Later, these microparticles were suspended into a co-dissolved solution that contained BH and a hydrophilic polymer (polypyrrolidone, PVP) and were co-electrospun into the nanofiber/microparticle hybrids. The EHDA processes were recorded, and the resultant trans-scale products showed a typical hybrid topography, with microparticles distributed all over the nanofibers, which was demonstrated by SEM assessments. FTIR and XRD demonstrated that the components within the hybrids were presented in an amorphous state and had fine compatibility with each other. In vitro dissolution tests verified that the hybrids were able to provide the designed dual-step drug release profiles, a combination of the fast release step of BH from the hydrophilic PVP nanofibers through an erosion mechanism and the sustained release step of BH from the insoluble CA microparticles via a typical Fickian diffusion mechanism. The present protocols pave a new way for developing trans-scale functional materials.

The influence of the ultrasonic treatment of working fluids on electrospun amorphous solid dispersions

Based on a working fluid consisting of a poorly water-soluble drug and a pharmaceutical polymer in an organic solvent, electrospinning has been widely exploited to create a variety of amorphous solid dispersions However, there have been very few reports about how to prepare the working fluid in a reasonable manner. In this study, an investigation was conducted to determine the influences of ultrasonic fluid pretreatment on the quality of resultant ASDs fabricated from the working fluids. SEM results demonstrated that nanofiber-based amorphous solid dispersions from the treated fluids treated amorphous solid dispersions exhibited better quality than the traditional nanofibers from untreated fluids in the following aspects: 1) a straighter linear morphology; 2) a smooth surface; and 3) a more evener diameter distribution. The fabrication mechanism associated with the influences of ultrasonic treatments of working fluids on the resultant nanofibers' quality is suggested. Although XRD and ATR-FTIR experiments clearly verified that the drug ketoprofen was homogeneously distributed all over the TASDs and the traditional nanofibers in an amorphous state regardless of the ultrasonic treatments, the in vitro dissolution tests clearly demonstrated that the TASDs had a better sustained drug release performance than the traditional nanofibers in terms of the initial release rate and the sustained release time periods.

Engineered Shellac Beads-on-the-String Fibers Using Triaxial Electrospinning for Improved Colon-Targeted Drug Delivery

Colon-targeted drug delivery is gradually attracting attention because it can effectively treat colon diseases. Furthermore, electrospun fibers have great potential application value in the field of drug delivery because of their unique external shape and internal structure. In this study, a core layer of hydrophilic polyethylene oxide (PEO) and the anti-colon-cancer drug curcumin (CUR), a middle layer of ethanol, and a sheath layer of the natural pH-sensitive biomaterial shellac were used in a modified triaxial electrospinning process to prepare beads-on-the-string (BOTS) microfibers. A series of characterizations were carried out on the obtained fibers to verify the process-shape/structure-application relationship. The results of scanning electron microscopy and transmission electron microscopy indicated a BOTS shape and core-sheath structure. X-ray diffraction results indicated that the drug in the fibers was in an amorphous form. Infrared spectroscopy revealed the good compatibility of the components in the fibers. In vitro drug release revealed that the BOTS microfibers provide colon-targeted drug delivery and zero-order drug release. Compared to linear cylindrical microfibers, the obtained BOTS microfibers can prevent the leakage of drugs in simulated gastric fluid, and they provide zero-order release in simulated intestinal fluid because the beads in BOTS microfibers can act as drug reservoirs.

Biphasic drug release from electrospun structures

INTRODUCTION

Biphasic release, as a special drug-modified release profile that combines immediate and sustained release, allows fast therapeutic action and retains blood drug concentration for long periods. Electrospun nanofibers, particularly those with complex nanostructures produced by multi-fluid electrospinning processes, are potential novel biphasic drug delivery systems (DDSs).

AREAS COVERED

This review summarizes the most recent developments in electrospinning and related structures. In this review, the role of electrospun nanostructures in biphasic drug release was comprehensively explored. These electrospun nanostructures include monolithic nanofibers obtained through single-fluid blending electrospinning, core-shell and Janus nanostructures prepared via bifluid electrospinning, three-compartment nanostructures obtained via trifluid electrospinning, nanofibrous assemblies obtained through the layer-by-layer deposition of nanofibers, and the combined structure of electrospun nanofiber mats with casting films. The strategies and mechanisms through which complex structures facilitate biphasic release were analyzed.

EXPERT OPINION

Electrospun structures can provide many strategies for the development of biphasic drug release DDSs. However, many issues such as the scale-up productions of complex nanostructures, the in vivo verification of the biphasic release effects, keeping pace with the developments of multi-fluid electrospinning, drawing support from the state-of-the-art pharmaceutical excipients, and the combination with traditional pharmaceutical methods need to be addressed for real applications.

Fast and convenient delivery of fluidextracts liquorice through electrospun core-shell nanohybrids

Introduction: As an interdisciplinary field, drug delivery relies on the developments of modern science and technology. Correspondingly, how to upgrade the traditional dosage forms for a more efficacious, safer, and convenient drug delivery poses a continuous challenge to researchers.

Methods, results and discussion: In this study, a proof-of-concept demonstration was conducted to convert a popular traditional liquid dosage form (a commercial oral compound solution prepared from an intermediate licorice fluidextract) into a solid dosage form. The oral commercial solution was successfully encapsulated into the core–shell nanohybrids, and the ethanol in the oral solution was removed. The SEM and TEM evaluations showed that the prepared nanofibers had linear morphologies without any discerned spindles or beads and an obvious core–shell nanostructure. The FTIR and XRD results verified that the active ingredients in the commercial solution were compatible with the polymeric matrices and were presented in the core section in an amorphous state. Three different types of methods were developed, and the fast dissolution of the electrospun core–shell nanofibers was verified.

Conclusion: Coaxial electrospinning can act as a nano pharmaceutical technique to upgrade the traditional oral solution into fast-dissolving solid drug delivery films to retain the advantages of the liquid dosage forms and the solid dosage forms.

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.

Piezoelectric Enhancement of Piezoceramic Nanoparticle-Doped PVDF/PCL Core-Sheath Fibers

Electrospinning is considered to be an efficient method to prepare piezoelectric thin films because of its ability to transform the phase of the polymers. A core-sheath structure can endow fibers with more functions and properties. In this study, fibers with a core-sheath structure were prepared using polyvinylidene fluoride (PVDF) included with nanoparticles (NPs) as the shell layer and polycaprolactone (PCL) as the core layer. Their mechanical and piezoelectric properties were studied in detail. During the course of the electrospinning process, PVDF was demonstrated to increase the amount of its polar phase, with the help of nanoparticles acting as a nucleating agent to facilitate the change. PCL was chosen as a core material because of its good mechanical properties and its compatibility with PVDF. Transmission electron microscope (TEM) assessments revealed that the fibers have a core-sheath structure, and shell layers were loaded with nanoparticles. Mechanical testing showed that the core layer can significantly improve mechanical properties. The XRD patterns of the core-sheath structure fibers indicated the β phase domain the main component. Piezoelectric testing showed that the doped nanoparticles were able to enhance piezoelectric performances. The increases of mechanical and piezoelectric properties of core-sheath structure fibers provide a feasible application for wearable electronics, which require flexibility and good mechanical properties.

Enhancement of AFB1 Removal Efficiency via Adsorption/Photocatalysis Synergy Using Surface-Modified Electrospun PCL-g-C3N4/CQDs Membranes

Aflatoxin B₁ (AFB₁) is a highly toxic mycotoxin produced by aspergillus species under specific conditions as secondary metabolites. In this study, types of PCL (Polycaprolactone) membranes anchored (or not) to g-C₃N₄/CQDs composites were prepared using electrospinning technology with (or without) the following surface modification treatment to remove AFB₁. These membranes and g-C₃N₄/CQDs composites were characterized by SEM, TEM, UV-vis, XRD, XPS and FTIR to analyze their physical and chemical properties. Among them, the modified PCL-g-C₃N₄/CQDs electrospun membranes exhibited an excellent ability to degrade AFB₁ via synergistic effects of adsorption and photocatalysis, and the degradation rate of 0.5 μg/mL AFB₁ solution was observed to be up to 96.88% in 30 min under visible light irradiation. Moreover, the modified PCL-g-C₃N₄/CQDs electrospun membranes could be removed directly after the reaction process without centrifugal or magnetic separation, and the regeneration was a green approach synchronized with the reaction under visible light avoiding physical or chemical treatment. The mechanism of adsorption by electrostatic attraction and hydrogen bonding interaction was revealed and the mechanism of photodegradation of AFB₁ was also proposed based on active species trapping experiments. This study illuminated the highly synergic adsorption and photocatalytic AFB₁ removal efficiency without side effects from the modified PCL-g-C₃N₄/CQDs electrospun membranes, thereby offering a continual and green solution to AFB₁ removal in practical application.

Electrospun fibers with blank surface and inner drug gradient for improving sustained release

New engineering methods and advanced strategies are highly desired for creating novel drug sustained release nanomaterials. In this study, a trilayer concentric spinneret was explored to implement several multifluid electrospinning processes. A trilayer core-shell nanofiber was successfully fabricated, which comprise a drug-free polymeric coating and an inner drug gradient distribution, and then compared with bilayer core-shell and monolithic medicated nanofibers. All the electrospun nanofibers similarly consisted of two components (guest drug acetaminophen and host polymer cellulose acetate) and presented a linear morphology. Due to the secondary interactions within nanofibers, loaded drug with amorphous state was detected, as demonstrated by SEM, DSC, XRD, and FTIR determinations. In vitro and in vivo gavage treatments to rats tests were carried out, the trilayer nanofiber with an elaborate structure design were demonstrated to provide better drug sustained release profile than the bilayer core-shell nanofibers in term of initial burst release, later tail-off release and long sustained release time period. The synergistic mechanism for improving the drug sustained release behaviors is disclosed. By breaking the traditional concepts about the implementation of multifluid electrospinning and the strategy of combining surface properties and inner structural characteristics, the present protocols open a new way for developing material processing methods and generating novel functional nanomaterials.

Recent Progress of the Preparation and Application of Electrospun Porous Nanofibers

Electrospun porous nanofibers have gained a lot of interest recently in various fields because of their adjustable porous structure, high specific surface area, and large number of active sites, which can further enhance the performance of materials. This paper provides an overview of the common polymers, preparation, and applications of electrospun porous nanofibers. Firstly, the polymers commonly used to construct porous structures and the main pore-forming methods in porous nanofibers by electrospinning, namely the template method and phase separation method, are introduced. Secondly, recent applications of electrospun porous nanofibers in air purification, water treatment, energy storage, biomedicine, food packaging, sensor, sound and wave absorption, flame retardant, and heat insulation are reviewed. Finally, the challenges and possible research directions for the future study of electrospun porous nanofibers are discussed.