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Progesterone (P4), commonly administered in high doses for endometrial cancer palliative management, has limitations in current delivery systems. This preliminary in vitro drug release study introduces electrospun patches to offer a new perspective on P4 delivery. The study aimed to assess the influence of the surfactant polysorbate 80 (PS80) on the release of P4 from polycaprolactone (PCL) fibers. The PS80 effects are examined to inform the fine‐tuning of the fibre generation process. Patches developed, PCL wet (with PS80) and PCL dry (without PS80), showed encapsulation efficiencies of 76% and 42%, respectively. The dose levels studied are 6.1 mg for PCL wet and 4.4 mg for PCL dry samples. Molecular studies show that higher surfactant levels improved P4‐polymer mixing, enhancing dissolution and release rates. Patches with PS80 released 66% of the drug in 17 h, while those without released only 51%. Release data best fit the Weibull model, showcasing promise for these patches in transdermal P4 delivery. This study offers a non‐invasive option compared to traditional methods and underscores the need for further research to confirm the patches' clinical effectiveness for potential use in gynecological oncology. [ABSTRACT FROM AUTHOR]

As a facile, efficient, and low‐cost fiber manufacturing strategy, pressurized gyration/rotation (PG) is attracting tremendous attention. This review provides a comprehensive introduction to the working setups, fundamental principles, processing parameters, and material feed properties of this technology. The characterizations of products prepared by this technology and their wide application fields are summarized. The development potentials and broader application prospects of PG are discussed. PG holds significant promise for the scale‐up of ultrafine fiber manufacturing. [ABSTRACT FROM AUTHOR]

This review focuses on the effects on the environment due to the production of polymer‐solvent solutions and the manufacture of polymeric fibers of thicknesses from a nanometer up to a millimeter using these solutions. The most common polymeric fiber manufacture methods are reviewed based on their effects on the environment, particularly from the use of hazardous materials and energy consumption. Published literature is utilized to analyze and quantify energy consumption of the manufacturing methods electrospinning, phase separation, self‐assembly, template synthesis, drawing and pressurized gyration. The results show that during the manufacturing stage of the lifecycle of polymeric fibers, pressurized gyration is more environmentally efficient primarily due to its mass‐producing features and fast processing of polymeric solutions into fibers, it also works best with water‐based solutions. Further green alternatives are described such as the use of sustainable polymers and solvents to enhance the environmental benefit. Overall, it is shown that the most effective method of curbing the environmental impact of manufacturing polymeric fibers is the use of nontoxic, water‐soluble polymers along with the evasion of toxic solvents. [ABSTRACT FROM AUTHOR]

An innovative development of pressurized gyration is presented, incorporating a directional nozzle system. Thus, nozzle‐pressurized gyration is used to prepare polymeric fibers. In this work, three different polymeric fibers (polycaprolactone, polyvinylpyrrolidone, and polyethylene oxide) manufactured by the original pressurized gyration and nozzle‐pressurized gyration are compared. Under the same processing parameters (working pressure, rotational speed, and collection distance), nozzle‐pressurized gyration is proved to be a highly efficient spinning technology for uniform and uniaxially oriented fiber products. The effects of the spinning vessel geometry on the morphology and alignment of gyrospun fibers are elucidated. This work also reveals the relationship between fiber morphology and collection distance in nozzle‐pressurized gyration. Varying the collection distance provides a useful approach to the synthesis of uniform fibers with anisotropic arrangement. [ABSTRACT FROM AUTHOR]

Cyclodextrins are a class of biocompatible and highly water‐soluble oligosaccharide polymers, with vast applications in industries ranging from drug delivery to agriculture. Currently, most fiber production relies on using environmentally unfriendly organic solvents and polymeric additions. Cyclodextrins are seldom used on their own without a carrier polymer, however in this work, (2‐hydroxypropyl)‐β‐cyclodextrin) fibers are successfully produced with water, as the "green" solvent with pressurized gyration and electrospinning, without using a carrier polymer. The average fiber diameter of the pressurized gyration produces fibers ranged between 5.5 and 5.8 µm, while the average fiber diameter of the electrospun fibers ranged between only 183 and 305 nm. These findings show the thinnest diameter of pure cyclodextrin fibers achieved in current literature. Both techniques have specific advantages, such as electrospinning being able to produce nanofibers, while pressurized gyration has productivity of over 1.5 g min−1. Here, a pioneering study into the production of cyclodextrin‐only fibers with two different fiber production techniques and the creation of a cyclodextrin‐super‐mat that combines both types of fibers is presented. [ABSTRACT FROM AUTHOR]

A composite nanofiber composed of three polymers, namely polyvinyl alcohol/polyvinyl pyrrolidone/polyethylene oxide, is produced. The experiments are constructed using three design of experiment techniques, Taguchi L9, Taguchi L27, and Screening method. The experiments are verified using the analysis of variance (ANOVA) method and later a mathematical model is developed using the regression method. The impact of electrospun processing parameters, namely applied voltage, flow rate, and working distance, on nanofibers' diameter is measured. The working distance is a significant factor in controlling the size of the fiber diameter, while the applied voltage has the lowest effect on it. As a result of the regression equation, a Genetic algorithm is used to find the optimum variables for the required fiber diameter, which is 156 nm for flow rate = 0.001 mL h−1, voltage = 30 kV, and distance = 200 mm with a 3% difference from the experimental fiber diameter. [ABSTRACT FROM AUTHOR]

Such resort to water as a polymer solvent and the increased use of oligosaccharides in polymeric applications will be an impetus to tackling the environmental friendliness, green manufacturing, and sustainability of more traditional polymers. In Alessandro Gandini and Talita M. Lacerda's article (2100902), furan-based polymers are critically reviewed as furan offers a versatile platform for producing various polymers from non-fossil sources and ecological benign processes. Self-healing polymers with dynamic bonds are attractive materials, which may also facilitate the recycling of thermosetting polymers SP [ sp 7 SP ] sp and rubbers. SP [ sp 8 SP ] sp However, many self-healing polymers still show inferior properties compared to their non-self-healing counterparts, which needs to be addressed. [Extracted from the article]

Poly(caprolactone; PCL)—poly(N‐isopropylacrylamie; PNIPAAm)—Fe3O4 fiber, that can be magnetically actuated, is reported. Here, a structure is engineered that can be utilized as a smart carrier for the release of chemotherapeutic drug via magneto‐thermal activation, with the aid of magnetic nanoparticles (MNPs). The magnetic measurement of the fibers revealed saturation magnetization values within the range of 1.2–2.2 emu g−1. The magnetic PCL‐PNIPAAm‐Fe3O4 scaffold shows a specific loss power value of 4.19 W g−1 at 20 wt% MNPs. A temperature increase of 40 °C led to a 600% swelling after only 3 h. Doxorubicin (DOX) as a model drug, demonstrates a controllable drug release profile. 39% ± 0.92 of the total drug loaded is released after 96 h at 37 °C, while 25% drug release in 3 h at 40 °C is detected. Cytotoxicity results show no significant difference in cell attachment efficiency between the MNP‐loaded fibers and control while the DOX‐loaded fibers effectively inhibited cell proliferation at 24 h matching the drug release profile. The noncytotoxic effect, coupled with the magneto‐thermal property and controlled drug release, renders excellent potential for these fibers to be used as a smart drug‐release agent for localized cancer therapy. [ABSTRACT FROM AUTHOR]

Abstract: In this invited feature article, the invention of pressurized gyration in 2013 and its subsequent development into sister processes such as pressurized melt gyration, infusion gyration, and pressure‐coupled infusion gyration is elucidated. The fundamentals of these processes are discussed, elucidating how these novel methods can be used to facilitate mass production of polymeric fibers and other morphologies. The effects of the main system parameters: rotational speed and gas pressure, are discussed along with the influence of solution parameters such as viscosity and polymer chain entanglement. The effect of flow of material into the gyrator in infused gyration is also illustrated. Examples of many polymers that have been subjected to these processes are discussed and the applications of resulting products are illustrated under several different research themes such as, tissue engineering, drug delivery, diagnostics, hydrogels, filtration, and wound healing. [ABSTRACT FROM AUTHOR]

Abstract: This short communication describes the design and assembly of a new, miniaturized electrospinner to produce nanofibers at the site of need for drug delivery and wound dressing applications. The portable apparatus would eliminate the storage and transportation concerns with regards to the delicate nature of drug‐loaded nanofibers, thereby preserving product integrity at the site of use. Furthermore, the setup features a smaller size, a cheaper price, and components that are readily obtainable off‐the‐shelf, compared to those of available devices that are custom‐built and more expensive, making it desirable and accessible for other users in the field. As a proof‐of‐concept for wound care, the device is successfully used to electrospin three types of nanofibers comprised of pure cellulose acetate (CA), and CA respectively doped with 0.75 and 1.5 wt% silver nanoparticles. The miniaturized device is useful on account of the popularity of electrospinning as well as the potential to minimize wound infection due to the reduced manipulation of both the dressing and the wound from product generation to the point of need. Work is in progress to further develop the portable device and compare its product performance with traditional wound dressing materials for clinical translation. [ABSTRACT FROM AUTHOR]

Abstract: Polymeric fibers are prepared by using electric field driven fiber production technology—electrospinning and pressure driven fiber production technology—pressurized gyration. Fibers of four different polymers: polyvinylidene fluoride (PVDF), poly(methyl methacrylate (PMMA), poly(N‐isopropylacrylamide), and polyvinylpyridine (PVP), are spun by both techniques and differences are analyzed for their suitability as drug carriers. The diameters of electrospun fibers are larger in some cases (PVDF and PMMA), producing fibers with lower surface area. Pressurized gyration allows for a higher rate of fiber production. Additionally, drug‐loaded PVP fibers are prepared by using two poorly water‐soluble drugs (Amphotericin B and Itraconazole). In vitro dissolution studies show differences in release rate between the two types of fibers. Drug‐loaded gyrospun fibers release the drugs faster within 15 min compared to the drug‐loaded electrospun fibers. The findings suggest pressurized gyration is a promising and scalable approach to rapid fiber production for drug delivery when compared to electrospinning. [ABSTRACT FROM AUTHOR]

Abstract: Bacterial cellulose (BC) is a very promising biological material. However, at present its utilization is limited by difficulties in shape forming it. In this Communication, it is shown how this can be overcome by blending it with poly(methylmethacrylate) (PMMA) polymer. BC:PMMA fibers are produced by pressurized gyration of blended BC:PMMA solutions. Subsequently, BC:PMMA bandage‐like scaffolds are generated with different blends. The products are investigated to determine their morphological and chemical features. Cell culture and proliferation tests are performed to obtain information on biocompatibility of the scaffolds. [ABSTRACT FROM AUTHOR]

Polymeric nanofibers are a fascinating class of material that has been widely used in a myriad of applications, including fiber reinforced composites, protective clothing, and chemical sensors. Here, the science of the combined application of external pressure, controlled infusion of polymer solution and gyration, which allows mass production of uniform polymeric nanofibers in a single step, is uncovered. Using poly(ethylene oxide) as an example this study shows the use of this novel method to fabricate polymeric nanofibers and nanofibrous mats under different combinations of processing parameters such as working pressure (1 × 105 to 3 × 105 Pa), rotational speed (10 000-36 000 rpm), infusion rate (500-5000 µL min−1), and fiber collection distance (4-15 cm). The morphologies of the nanofibers are characterized using scanning electron microscopy and anisotropy of alignment of fiber is studied using 2D fast Fourier transform analysis. A correlation between the product morphology and the processing parameters is established. The produced fibers are in a range of 50-850 nm at an orifice-to-collector distance of 10 cm. The results indicate that the pressure coupled infusion gyration (PCIG) offers a facile way for forming nanofibers and nanofiber assemblies. [ABSTRACT FROM AUTHOR]

A pressurized melt gyration process has been used for the first time to generate poly(ε-caprolactone) (PCL) fibers. Gyration speed, working pressure, and melt temperature are varied and these parameters influence the fiber diameter and the temperature enabled changing the surface morphology of the fibers. Two types of nonwoven PCL fiber constructs are prepared. First, Ag-doped PCL is studied for antibacterial activity using Gram-negative Escherichia coli and Pseudomonas aeruginosa microorganisms. The melt temperature used to make these constructs significantly influences antibacterial activity. Neat PCL nonwoven scaffolds are also prepared and their potential for application in muscular tissue engineering is studied with myoblast cells. Results show significant cell attachment, growth, and proliferation of cells on the scaffolds. [ABSTRACT FROM AUTHOR]

In article number 1900394 by Mohan Edirisinghe and co-workers, a method for fabricating porogen-free gelatin scaffolds with a narrow pore size distribution using simple T-junction microfluidics is described. It offers an economical approach for the preparation of gelatin scaffolds with homogenous porosity which can be utilized in diverse healthcare engineering applications, especially in pore size dependent scenarios. [Extracted from the article]

Silk has attracted considerable interest for use in biomedical applications due to its high strength and promising biocompatibility. Degummed silk, consisting only of silk fibroin (SF), has been processed using various methods and can be made into films, sponges, and fibers. Pressurized gyration (PG) is capable of rapidly producing aligned fibers and offers a great amount of control over their structure and morphology. Here, SF fibers are produced for the first time using PG. The effect of varying SF concentration and applied working pressure to the gyration vessel is reported, along with the resulting effect on fiber diameter, morphology, and structural composition. Aligned microfibers are found at concentrations of 8, 10, 12 w/v%, with the lowest fiber diameters reported at 8 w/v% SF 0.3 MPa applied pressure (2.1 ± 1.3 µm). Fourier‐transform infrared spectroscopy (FTIR) confirms the existence of PG spun fibers in both random coil and β‐sheet formations. Pressurized gyration produces aligned fibers with good control over structure and morphology. Silk fibroin fibers are produced for the first time using pressurized gyration. The effect of varying polymer concentration and applied working pressure in the gyration vessel on the output fiber diameter, and morphology is reported. Silk fibroin exists in the fibers in random coil and β‐sheet conformations. [ABSTRACT FROM AUTHOR]

Pressurized gyration and its sister processes are novel methods to produce polymeric fibers. Potential applications for such fibers include wound dressings, tissue engineering scaffolds, and filters. This study reports on a pressurized gyration technique that employs pressured N2 gas to prepare biocompatible wound dressing bandages from bacterial cellulose and poly (methylmethacrylate) polymer blended with alloyed antimicrobial nanoparticles. Resulting bandages are manufactured with high product yield and characterized for their chemical, physical, and mechanical properties. Increased density in solutions with additional antimicrobial nanoparticles results in increased fiber diameters. Also, addition of antimicrobial nanoparticles enhances ultimate tensile strength and Young's modulus of the bandages. Typical molecular bonding in the bandages is confirmed by Fourier‐transform infrared spectroscopy, with peaks that have higher intensity and narrowing points being caused by additional antimicrobial nanoparticles. More so, the cellular response to the bandages and the accompanying antimicrobial activity are studied in detail by in vitro co‐culture of Staphylococcus aureus and keratinocytes. Antimicrobial nanoparticle‐loaded bandage samples show increased cell viability and bacteria inhibition during co‐culture and are found to have a promising future as epidermal wound dressing materials. Bacterial cellulose‐polymer‐antimicrobial nanoparticle blends are processed using pressurized gyration to manufacture wound dressing bandages which are characterized by measuring product yield, fiber morphology, structure and many key bandage‐properties. In vitro co‐culture tests are performed to investigate biocompatibility and accompanying antimicrobial activity using Staphylococcus aureus and keratinocytes. Some bandages show significant higher cell viability and bacteria inhibition. [ABSTRACT FROM AUTHOR]

This work explores the application of Allium sativum (Garlic) extract, in the creation of novel polymeric core‐sheath fibers for wound therapy applications. The core‐sheath pressurized gyration (CS PG) technology is utilized to mass‐produce fibers with a polycaprolactone (PCL) core and a polyethylene oxide (PEO) sheath, loaded with garlic extract. The produced fibers maintain structural integrity, long‐term stability and provide a cell‐friendly surface with rapid antibacterial activity. The physical properties, morphology, therapeutic delivery, cytotoxicity, thermal and chemical stability of PCL, PEO, PEO/Garlic, Core‐Sheath (CS) PEO/PCL and PEO/Garlic/PCL fibers are analyzed. Findings show that the addition of garlic extract greatly increases the fibers’ thermal durability, while decreasing their diameter, thus improving cell adhesion and proliferation. In‐vitro release tests reveal a rapid release of garlic extract, which has significant antibacterial action against both Gram‐negative Escherichia coli (E. coli) and Gram‐positive Staphylococcus aureus (S. aureus) bacteria species. Cell viability experiments validate the fiber samples' biocompatibility and nontoxicity, making them appropriate for integrative medicine applications. These core‐sheath structures emphasize the potential of combining natural therapeutic agents with advanced material technologies to develop cost‐effective, sustainable and highly effective wound dressings, offering a promising solution to the growing concerns associated with conventional synthetic antibacterial agents. [ABSTRACT FROM AUTHOR]

Front Cover: A novel, commercially viable one‐pot gyratory process which allows polymeric nanofibers to be tailor‐made to structural specifications has been discovered. Its superiority is in the fact that it allows the simultaneous use of four process control parameters; composition, rotation speed, feed flow rate, and pressure. Process design and extensive trials elucidate the very significant prowess and potential of the new process in the production of nano‐fibrous structures for diverse applications where both random and aligned fibrous structures with and without beads are desired. This is reported by Xianze Hong, Suntharavathanan Mahalingam, and Mohan Edirisinghe, in article number 1600564. [ABSTRACT FROM AUTHOR]

Front Cover: Pressurised melt gyration is a novel solvent‐free process which manufactures suitably doped non‐woven polymeric fibres for healthcare applications such as antibacterial and tissue engineering. Polymer jetting through coarse holes in the gyrating pot creates fibres. Their size can be controlled using gyration speed, temperature and pressure. Further details can be found in the article by Zewen Xu, Sunthar Mahalingam, Pooja Basnett, Bahijja Raimi‐Abraham, Ipsita Roy, Duncan Craig and Mohan Edirisinghe* on page 922. [ABSTRACT FROM AUTHOR]