Buschhutchison1180

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Hierarchically ordered planar and spherical membranes (sacs) were constructed using amphiphilic and cationic β-sheet peptides that spontaneously assembled together with negatively charged alginate solution. The system was found to form either a fully developed membrane structure with three distinct regions including characteristic perpendicular fibers or a non-fully developed contact layer lacking these standing fibers, depending on the peptide age, membrane geometry and membrane incubation time. The morphological differences were found to strongly depend on fairly-long incubation time frames that influenced both the peptide's intrinsic alignment and the reaction-diffusion process taking place at the interface. A three-stage mechanism was suggested and key parameters affecting the development process were identified. Stability tests in biologically relevant buffers confirmed the suitability of these membranes for bio applications.Nosocomial infections resulting from bacterial attachment on blood-contacting medical devices, as well as biofilm and thrombus formation caused by fibrin crosslinking and platelet accumulation/activation are a major health concern and may lead to severe morbidity and mortality. Therefore, there is an urgent need to develop facile and efficient surface coatings with both antibiofilm and antithrombotic properties to prevent medical-device associated infections as well as thrombus formation. In this study, the copolymers containing quaternary ammonium (QA) and phosphorylcholine (PC) groups were synthesized through traditional free-radical copolymerization. The cationic group of QA provides bactericidal properties, and the cell membrane-mimicking group of PC provides antithrombotic and antifouling properties. Long-term stability of the copolymer coating was achieved via simple dip coating. X-ray photoelectron spectroscopy and water contact angle measurement demonstrated that the QA and PC groups possessed inversion properties once in contact with water allowing for long-term stability. Scanning electron microscopy and confocal laser scanning microscopy demonstrated that the copolymer coating could maintain antibiofilm properties for one week in a nutrient-rich environment. Furthermore, the copolymer coating significantly decreased platelet adhesion/activation and did not cause hemolysis. The ex vivo blood circulation showed no thrombus formation which confirmed the excellent antithrombotic property of the copolymer coating. Such coatings that maintain high cell viability and exhibit both antibiofilm and antithrombotic properties present potential applications for blood-contacting devices.Conductive self-healing hydrogels as a fascinating class of materials have received much attention in recent years and been widely used in many fields. However, a long healing time and poor electrical conductivity have limited their extended applications. To overcome these shortcomings, we fabricated an excellent conductive self-healing hydrogel by embedding a nanocomposite of Ag nanoparticles and reduced graphene oxide (Ag/RGO) in PVA-borax dynamic networks, which exhibits a relatively high conductivity (4.43 S m-1), good flexibility and excellent self-healing properties without any external stimuli. The multifunctional hydrogel could self-heal within 3 s at room temperature. It also exhibits an excellent free-shapeable property like clay such that it can be modeled into any different complex geometrical shape as desired. It is expected to have potential applications in many fields such as flexible electronic wearable devices, sensors, rechargeable batteries, and biomaterials.The COVID-19 pandemic has sparked a demand for safe and highly effective decontamination techniques for both personal protective equipment (PPE) and hospital and operating rooms. The gradual lifting of lockdown restrictions warrants the expansion of these measures into the outpatient arena. Ultraviolet C (UVC) radiation has well-known germicidal properties and is among the most frequently reported decontamination techniques used today. However, there is evidence that wavelengths beyond the traditional 254 nm UVC - namely far UVC (222 nm), ultraviolet B, ultraviolet A, visible light, and infrared radiation - have germicidal properties as well. This review will cover current literature regarding the germicidal effects of wavelengths ranging from UVC through the infrared waveband with an emphasis on their activity against viruses, and their potential applicability in the healthcare setting for general decontamination during an infectious outbreak.This study was conducted to develop biodegradable cellulose scaffolds by oxidising porous cellulose sponges for tissue engineering applications. Cellulose powder was dissolved in ionic liquid using a salt leaching method, and porous cellulose scaffolds of various pore sizes were prepared. The scaffolds were oxidised with periodate to introduce aldehyde at a rate controlled by the periodate concentration. Oxidised scaffolds exhibited weight loss in cell culture medium, but not in phosphate buffer. Therefore, we confirmed that Schiff base formation between the aldehyde and amino groups through a Maillard reaction triggered cellulose molecular degradation. The degradation rate was controlled by the oxidation degree, whereas the aldehyde content controlled protein adsorption and cell proliferation. Additionally, in vivo implantation tests revealed that optimising the oxidation ratio not only improved biodegradability but also reduced inflammation. In conclusion, our results suggest that simple oxidised cellulose is useful as a low-toxicity biodegradable scaffold.Polyoxometalates (POMs) as a kind of molecular metal-oxide cluster with precise chemical composition and architecture have been demonstrated to show potential in multidisciplinary materials. Accompanied by their bioactivities, POM clusters have also been shown to be capable of sensing diseases and allowing synergistic therapy based on their redox and near infrared absorption. In parallel with metal nanoparticles and organic materials, these inorganic clusters have also displayed unique photothermal imaging and therapeutic properties over recent years. In this review, we outlined the main achievements of POMs in the fields of bio-detecting probes and the photothermal effect. Fluorescence detection, magnetic resonance, computed tomography, and photothermal property-supported photoacoustic imaging acting as a multifunction platform that integrates photothermal therapy (PTT) were discussed at the same time. this website The comparison of nanocomposites to POMs alone in imaging-guided PTT, multi-modal imaging, and the combination of PTT with controlled chemotherapy and gas therapy were described in detail.