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The use of Intraoperative Cell Salvage (ICS) is currently limited in oncological surgeries, due to safety concerns associated with the ability of existing devices to successfully remove circulating tumour cells. In this work, we present the first stages towards the creation of an alternative platform to current cell savers, based on the extremely selective immunoaffinity membrane chromatography principle. Non-woven membranes were produced via electrospinning using poly(vinyl alcohol) (PVA), and further heat treated at 180 °C to prevent their dissolution in aqueous environments and preserve their fibrous morphology. The effects of the PVA degree of hydrolysis (DH) (98 % vs 99 %), method of electrospinning (needleless DC vs AC), and heat treatment duration (1-8 h) were investigated. All heat treated supports maintained their cytocompatibility, whilst tensile tests indicated that the 99 % hydrolysed DC electrospun mats were stronger compared to their 98 % DH counterparts. Although, and at the described conditions, AC electrospinning produced fibres with more than double the diameter compared to those from DC electrospinning, it was not chosen for subsequent experiments because it is still under development. Evidence of unimpeded passage of SY5Y neuroblastoma cells and undiluted defibrinated sheep's blood in flow-through filtration experiments confirmed the successful creation of 3D networks with minimum resistance to mass transfer and lack of non-specific cell binding to the base material, paving the way for the development of novel, highly selective ICS devices for tumour surgeries., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Eirini Theodosiou reports financial support was provided by The Royal Society. Eirini Theodosiou reports financial support was provided by The Birmingham Orthopaedic Charity. Vera Jencova reports financial support was provided by The Czech Health Research Council., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Magnetosomes are nano-sized magnetic nanoparticles with exquisite properties that can be used in a wide range of healthcare and biotechnological applications. They are biosynthesised by magnetotactic bacteria (MTB), such as Magnetospirillum gryphiswaldense MSR-1 ( Mgryph ). However, magnetosome bioprocessing yields low quantities compared to chemical synthesis of magnetic nanoparticles. Therefore, an understanding of the intracellular metabolites and metabolic networks related to Mgryph growth and magnetosome formation are vital to unlock the potential of this organism to develop improved bioprocesses. In this work, we investigated the metabolism of Mgryph using untargeted metabolomics. Liquid chromatography-mass spectrometry (LC-MS) was performed to profile spent medium samples of Mgryph cells grown under O 2 -limited ( n = 6) and O 2 -rich conditions ( n = 6) corresponding to magnetosome- and non-magnetosome producing cells, respectively. Multivariate, univariate and pathway enrichment analyses were conducted to identify significantly altered metabolites and pathways. Rigorous metabolite identification was carried out using authentic standards, the Mgryph -specific metabolite database and MS/MS mzCloud database. PCA and OPLS-DA showed clear separation and clustering of sample groups with cross-validation values of R 2 X = 0.76, R 2 Y = 0.99 and Q 2 = 0.98 in OPLS-DA. As a result, 50 metabolites linked to 45 metabolic pathways were found to be significantly altered in the tested conditions, including: glycine, serine and threonine; butanoate; alanine, aspartate and glutamate metabolism; aminoacyl-tRNA biosynthesis and; pyruvate and citric acid cycle (TCA) metabolisms. Our findings demonstrate the potential of LC-MS to characterise key metabolites in Mgryph and will contribute to further understanding the metabolic mechanisms that affect Mgryph growth and magnetosome formation., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

One of the current challenges in burn wound care is the development of multifunctional dressings that can protect the wound from bacteria or organisms and promote skin regeneration and tissue reconstitution. To this end, we report the design and fabrication of a composite electrospun membrane, comprised of electrospun polylactide: poly(vinyl pyrrolidone)/polylactide: poly(ethylene glycol) (PLA:PVP/PLA:PEG) core/shell fibers loaded with bioactive agents, as a functionally integrated wound dressing for efficient burns treatment. Different mass ratios of PLA:PVP in the shell were screened to optimize mechanical, physicochemical, and biological properties, in addition to controlled release profiles of loaded antimicrobial peptides (AMPs) from the fibers for desirable antibacterial activity. Fibroblasts were shown to readily adhere and proliferate when cultured on the membrane, indicating good in vitro cytocompatibility. The introduction of PLA beads by electrospraying on one side of the membrane resulted in biomimetic micro-nanostructures similar to those of lotus leaves. This designer structure rendered the composite membranes with superhydrophobic property to inhibit the adhesion/spreading of exogenous bacteria and other microbes. The administration of the resulting composite fibrous membrane on burnt skin in an infected rat model led to faster healing than a conventional product (sterile silicone membrane) and control detailed herein. These composite fibrous membranes loaded with bioactive drugs provide an integrated strategy for promoting burn wound healing and skin regeneration. STATEMENT OF SIGNIFICANCE: To address an urgent need in complex clinical requirements on developing a new generation of wound dressings with integrated functionalities. This article reports research work on a hierarchical fiber/bead composite membranes design, which combines a lotus-leaf-like superhydrophobic surface with drugs preloaded in the core and shell of fibers for effective burn treatment. This demonstrates a balance between simplified preparation processes and increased multifunctionality of the wound dressings. The creation of hierarchically structured surfaces can be readily achieved by electrospinning, and the composite dressings possessed a considerable mechanical strength, effective wound exudate absorption and permeability, good biocompatibility, broad antibacterial ability and promoting wound healing etc. Thus, our work unveils a promising strategy for the development of functionally integrated wound dressings for burn wound care., (Copyright © 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Spin coating polymer blend thin films provides a method to produce multiphase functional layers of high uniformity covering large surface areas. Applications for such layers include photovoltaics and light-emitting diodes where performance relies upon the nanoscale phase separation morphology of the spun film. Furthermore, at micrometer scales, phase separation provides a route to produce self-organized structures for templating applications. Understanding the factors that determine the final phase-separated morphology in these systems is consequently an important goal. However, it has to date proved problematic to fully test theoretical models for phase separation during spin coating, due to the high spin speeds, which has limited the spatial resolution of experimental data obtained during the coating process. Without this fundamental understanding, production of optimized micro- and nanoscale structures is hampered. Here, we have employed synchronized stroboscopic illumination together with the high light gathering sensitivity of an electron-multiplying charge-coupled device camera to optically observe structure evolution in such blends during spin coating. Furthermore the use of monochromatic illumination has allowed interference reconstruction of three-dimensional topographies of the spin-coated film as it dries and phase separates with nanometer precision. We have used this new method to directly observe the phase separation process during spinning for a polymer blend (PS-PI) for the first time, providing new insights into the spin-coating process and opening up a route to understand and control phase separation structures.

Two series of poly(ethylene oxide)-tetrapeptide conjugates have been prepared using a "Click" reaction between an alkyne-modified tetra(phenylalanine) or tetra(valine) and various azide-terminated poly(ethylene oxide) (PEO) oligomers. Three different PEO precursors were used to prepare these conjugates, with number-average molecular weights of 350, 1200, and 1800 Da. Assembly of mPEO-F4-OEt and mPEO-V4-OEt conjugates was achieved by dialysis of a THF solution of the conjugate against water or by direct aqueous rehydration of a thin film. The PEO length has a profound effect on the outcome of the self-assembly, with the F4 conjugates giving rise to nanotubes, fibers, and wormlike micelles, respectively, as the length of the PEO block is increased. For the V4 series, the propensity to form beta-sheets dominates, and hence, the self-assembled structures are reminiscent of those formed by peptides alone, even at the longer PEO lengths. Thus, this systematic study demonstrates that the self-assembly of PEO-peptides depends on both the nature of the peptides and the relative PEO block length.

A new poly(ethylene oxide)-tetraphenylalanine polymer-peptide conjugate has been prepared via a "click" reaction between an alkyne-modified peptide and an azide-terminated PEO oligomer. Self-assembled nanotubes are formed after dialysis of a THF solution of this polymer-peptide conjugate against water. The structure of these nanotubes has been probed by circular dichroism, IR, TEM, and SAXS. From these data, it is apparent that self-assembly involves the formation of antiparallel beta-sheets and pi-pi-stacking. Nanotubes are formed at concentrations between 2 and 10 mg mL(-1). Entanglement between adjacent nanotubes occurs at higher concentrations, resulting in the formation of soft hydrogels. Gel strength increases at higher polymer-peptide conjugate concentration, as expected.