Optimised release of tetracycline hydrochloride from core-sheath fibres produced by pressurised gyration

In recent years, there has been a surge of interest in the design, processing, and use of core-sheath fibres, especially in the production of wound healing bandages and drug delivery. In this research, a novel core-sheath pressurised gyration technique was utilised to create antibacterial fibre patches (tetracycline hydrochloride, TEHCL) using polyvinyl pyrrolidone (PVP) and polycaprolactone (PCL). Antibiotic patches showed uniform fibres with a porous surface giving rise to a biphasic delivery system, which provided an initial burst of 30–48% drug release in the first 24 h followed by a constant rate of release throughout the course of 168 h, suitable for wound-dressings application. The effect of operating parameters on fibre morphology, the influence of the coresheath structure and drug loading as well as a mathematical modelling was investigated and analysed. Fouriertransform infrared spectroscopy, and differential scanning calorimetry results demonstrated successful TEHCL encapsulation as well as the presence of both polymers in the core-sheath fibres. The surface morphology of the fibres was studied using scanning electron microscopy and the core-sheath structure was verified using confocal scanning microscopy. Therefore, the core-sheath pressurised gyration method offers an exciting chance to customise fibre patches in a hybrid polymeric system. These advancements are crucial in the world of healthcare to meet demands where antibacterial dressings cannot be produced rapidly or when a personalised approach is necessary

Nozzle-Pressurized Gyration: A Novel Fiber Manufacturing Process

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

Anti-fungal bandages containing cinnamon extract

© 2019 The Authors. International Wound Journal published by Medicalhelplines.com Inc and John Wiley & Sons Ltd.Cinnamon-containing polycaprolactone (PCL) bandages were produced by pressurised gyration and their anti-fungal activities against Candida albicans were investigated. It was found that by preparing and spinning polymer solutions of cinnamon with PCL, fibres capable of inhibiting fungal growth could be produced, as observed in disk diffusion tests for anti-fungal susceptibility. Fascinatingly, compared with raw cinnamon powder, the novel cinnamon-loaded fibres had outstanding long-term activity. The results presented here are very promising and may indeed accelerate a new era of using completely natural materials in biomedical applications, especially in wound healing.Peer reviewe

Environmental Impact of Polymer Fiber Manufacture

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

Comparative Study of the Antimicrobial Effects of Tungsten Nanoparticles and Tungsten Nanocomposite Fibres on Hospital Acquired Bacterial and Viral Pathogens

© 2020 The Author(s). This is an open access article distributed under the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.A significant proportion of patients acquire hospital associated infections as a result of care within the NHS each year. Numerous antimicrobial strategies, such as antibiotics and surface modifications to medical facilities and instruments, have been devised in an attempt to reduce the incidence of nosocomial infections, but most have been proven unsuccessful and unsustainable due to antibiotic resistance. Therefore, the need to discover novel materials that can combat pathogenic microorganisms is ongoing. Novel technologies, such as the potential use of nanomaterials and nanocomposites, hold promise for reducing these infections in the fight against antimicrobial resistance. In this study, the antimicrobial activity of tungsten, tungsten carbide and tungsten oxide nanoparticles were tested against Escherichia coli, Staphylococcus aureus and bacteriophage T4 (DNA virus). The most potent nanoparticles, tungsten oxide, were incorporated into polymeric fibres using pressurised gyration and characterised using scanning electron microscopy and energy dispersive X-ray spectroscopy. The antimicrobial activity of tungsten oxide/polymer nanocomposite fibres was also studied. The results suggest the materials in this study promote mediation of the inhibition of microbial growth in suspension.Peer reviewe

Sludge-derived biochar: Physicochemical characteristics for environmental remediation

The global production of fecal wastes is envisioned to reach a very high tonnage by 2030. Perilous handling and consequential exposition of human and animal fecal matter are inextricably linked with stunted growth, enteric diseases, inadequate cognitive skills, and zoonoses. Sludge treatment from sewage and water treatment processes accounts for a very high proportion of overall operational expenditure. Straightforward carbonization of sludges to generate biochar adsorbents or catalysts fosters a circular economy, curtailing sludge processing outlay. Biochars, carbonaceous substances synthesized via the thermochemical transformation of biomass, possess very high porosity, cation exchange capacity, specific surface area, and active functional sorption sites making them very effective as multifaceted adsorbents, promoting a negative carbon emission technology. By customizing the processing parameters and biomass feedstock, engineered biochars possess discrete physicochemical characteristics that engender greater efficaciousness for adsorbing various contaminants. This review provides explicit insight into the characteristics, environmental impact considerations, and SWOT analysis of different sludges (drinking water, fecal, and raw sewage sludge) and the contemporary biochar production, modification, characterization techniques, and physicochemical characteristics, factors influencing the properties of biochars derived from the aforestated sludges, along with the designing of chemical reactors involved in biochar production. This paper also manifests a state-of-the-art discussion of the utilization of sludge-derived biochars for the eviction of toxic metal ions, organic compounds, microplastics, toxic gases, vermicomposting approaches, and soil amelioration with an emphasis on biochar recyclability, reutilization, and toxicity. The practicability of scaling up biochar generation with multifaceted, application-accustomed functionalities should be explored to aggrandize socio-economic merits

Nanofiber Based on Electrically Conductive Materials for Biosensor Applications

Biosensors are analytical tools that enable the transmission of different signals produced from the target analyte to a transducer for the production of real-time clinical diagnostic devices by obtaining meaningful results. Recent research demonstrates that the production of structured nanofiber through various methods has come to light as a potential platform for enhancing the functionality of biosensing devices. The general trend is towards the use of nanofibers for electrochemical biosensors. However, optical and mechanical biosensors are being developed by functionalization of nanofibers. Such nanofibers exhibit a high surface area to volume ratio, surface porosity, electroconductivity and variable morphology. In addition, nanosized structures have shown to be effective as membranes for immobilizing bioanalytes, offering physiologically active molecules a favorable microenvironment that improves the efficiency of biosensing. Cost effective, wearable biosensors are crucial for point of care diagnostics. This review aims to examine the electrically conductive materials, potential forming methods, and wide-ranging applications of nanofiber-based biosensing platforms, with an emphasis on transducers incorporating mechanical, electrochemical and optical and bioreceptors involving cancer biomarker, urea, DNA, microorganisms, primarily in the last decade. The appealing properties of nanofibers mats and the attributes of the biorecognition components are also stated and explored. Finally, consideration is given to the difficulties now affecting the design of nanofiber-based biosensing platforms as well as their future potential

Solubility–spinnability map and model for the preparation of fibres of polyethylene (terephthalate) using gyration and pressure

AbstractThe selection of a solvent or a solvent system is a fundamental and a crucial step in spinning fibres using a selected process. Solvent selection determines the critical minimum polymer concentration and the critical minimum chain entanglement which allows the spinning of nanofibres rather than other hybrid morphologies such as beaded structures. Pressurised gyration, which simultaneously combines the use of gas pressure and rotation, is used as the processing and forming route for spinning fibres in this work. This study investigates 23 different solvents and solvent systems spread on a wide area of a Teas graph and able to dissolve the functional polymer polyethylene (terephthalate) (PET) and spin products by the application of pressurised gyration. The results are mapped on a Teas graph to identify the solubility–spinnability region. Based on this solubility–spinnability region, various solvents and binary solvent systems that allow the making of PET fibres are suggested. Scaling laws for the relationship between polymer concentration and specific viscosity are identified. The structural evolution in the fibres prepared is elucidated. For the first time, a mathematical model to scale fibre diameter with respect to flow properties and processing parameters encountered in pressurised gyration has been successfully developed