BackgroundAcute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are important causes of morbidity and mortality in critically ill patients. Gastric contents aspiration is one of the most common causes of ALI/ARDS. To date, there are still no specific and effective pharmacological treatments for ALI/ARDS. Polyvinylalcohol-carbazate (PVAC), a polymer that can bind endogenous aldehydes, neutralize oxidative stress and inhibit inflammatory factors, may be a potential treatment for ALI/ARDS.MethodsA hydrochloric acid (HCl) induced mouse model was employed to assess the effect of PVAC. The changes of lung mechanics, pulmonary edema, histology and immune cells, cytokines, and lipid mediators in bronchioalveolar lavage fluid (BALF) were investigated in HCl-challenged mice.ResultsIn the HCl model, PVAC administration alleviated airway hyperresponsiveness and improved pulmonary edema and damage. In addition, it decreased the recruitment of neutrophils to the lung, and inhibited the increase of IL-6, TNF-α and leukotriene B4.ConclusionThese data indicates that PVAC is a potential candidate for the treatment of ALI/ARDS induced by aspiration of gastric acid or for the control of “asthma-like” symptoms in patients with gastroesophageal reflux.

In this paper, we present the synthesis of poly(beta-amino ester)-based solid polymer electrolytes (SPE) from off-stoichiometric acrylate-amine formulations using one-step, catalyst and solvent free aza-Michael addition. By varying the monomers, the pendant functionality of the polymer chain structure could be altered. All synthesized polymers yield freestanding and easy to handle electrolyte films and hence are evaluated as a new class of SPEs. The SPE with 1,4-butanediol diacrylate and propylamine showed the highest conductivity of 1.15 x 10-7 S cm-1 at 30 degrees C with 10 wt% lithium bis(trifluoromethanesulfonyl)imide. Because of the presence of the various functional groups in the structure, the polymer chain aids in the movement of both the anion and the cation. The fundamental aza-Michael addition is used to synthesize and characterize an extremely modular system for solid polymer electrolytes. The electrolyte films are produced through an environmentally friendly approach as they are catalyst and solvent free. A conductivity of 1.15 x 10-7 S cm-1 at 30 degrees C is attained from a polymer network comprising of 1,4-butanediol diacrylate and propylamine.image

The use of DEHP (diethylhexyl phthalate) is now banned for most applications in Europe; the exception is for blood bags, where its toxicity is overshadowed by its ability to extend the storage life of red blood cells. Another plasticiser, BTHC (butanoyl trihexyl citrate), is used in paediatric blood bags but does not stabilise blood cells as effectively. Interactions between plasticisers and lipids are investigated with a phospholipid, DMPC, to understand the increased stability of blood cells in the presence of DEHP as well as bioaccumulation and identify differences with BTHC. Mixed monolayers of DMPC and DEHP or BTHC were studied on Langmuir troughs where surface pressure/area isotherms can be measured. Neutron reflection measurements were made to determine the composition and structure of these mixed layers. A large amount of plasticiser can be incorporated into a DMPC monolayer but once an upper limit is reached, plasticiser is selectively removed from the interface at high surface pressures. The upper limit is found to occur between 40-60 mol% for DEHP and 20-40 mol% for BTHC. The areas per molecule are also different with DEHP being in the range of 50-100 angstrom 2 and BTHC being 65-120 angstrom 2. Results indicate that BTHC does not fit as well as DEHP in DMPC monolayers which could help explain the differences observed with regards to the stability of blood cells. The use of DEHP (diethylhexyl phthalate) is now banned for most applications in Europe; the exception is for blood bags, where its toxicity is overshadowed by its ability to extend the storage life of red blood cells.

Background During the past few decades, drug delivery system (DDS) has attracted many interests because it could enhance the therapeutic effects of drugs and reduce their side effects. The advent of nanotechnology has promoted the development of nanosized DDSs, which could promote drug cellular uptake as well as prolong the half-life in blood circulation. Novel polymer micelles formed by self-assembly of amphiphilic polymers in aqueous solution have emerged as meaningful nanosystems for controlled drug release due to the reversible destabilization of hydrophobic domains under different conditions. Results The amphiphilic polymers presented here were composed of cholesterol groups end capped and poly (poly (ethylene glycol) methyl ether methacrylate) (poly (OEGMA)) as tailed segments by the synthesis of cholesterol-based initiator, followed by atom transfer radical polymerization (ATRP) with OEGMA monomer. FT-IR and NMR confirmed the successfully synthesis of products including initiator and polymers as well as the Mw of the polymers were from 33,233 to 89,088 g/mol and their corresponding PDI were from 1.25 to 1.55 by GPC. The average diameter of assembled polymer micelles was in hundreds nanometers demonstrated by DLS, AFM and SEM. The behavior of the amphiphilic polymers as micelles was investigated using pyrene probing to explore their critical micelle concentration (CMC) ranging from 2.53 × 10 −4 to 4.33 × 10 −4 mg/ml, decided by the balance between cholesterol and poly (OEGMA). Besides, the CMC of amphiphilic polymers, the quercetin (QC) feeding ratio and polarity of solvents determined the QC loading ratio maximized reaching 29.2% certified by UV spectrum, together with the corresponding size and stability changes by DLS and Zeta potential, and thermodynamic changes by TGA and DSC. More significantly, cholesterol end-capped polymer micelles were used as nanosized systems for controlled drug release, not only alleviated the cytotoxicity of QC from 8.6 to 49.9% live cells and also achieved the QC release in control under different conditions, such as the presence of cyclodextrin (CD) and change of pH in aqueous solution. Conclusions The results observed in this study offered a strong foundation for the design of favorable polymer micelles as nanosized systems for controlled drug release, and the molecular weight adjustable amphiphilic polymer micelles held potential for use as controlled drug release system in practical application.

Plasticisers are widely used to provide desirable mechanical properties of many polymeric materials. These small molecule additives are also known to leach from the finished products, and this not only may modify the physical properties but the distribution of these materials in the environment and in the human body can cause long-term health concerns and environmental challenges. Many of these plasticisers are esters of polyvalent acids and phthalic acid has previously been predominant but various alternatives are now being more widely explored. The eventual distribution of these compounds depends not just on solubility in aqueous media and on vapour pressure but also on their interaction with other materials, particularly lipids and amphiphiles. This review provides an overview of both the basic physical data (solubility, partition coefficients, surface tension, vapour pressure) that is available in the literature and summarises what has been learnt about the molecular interactions of various plasticisers with surfactants and lipids.

A Mechanical Robust yet highly Conductive Diblock Copolymer-based Solid Polymer Electrolyte for Room Temperature Structural Battery Applications

Background and objectives The objective of this study was to investigate whether a soluble polymer and aldehyde-scavenger, polyvinylalcohol-carbazate (PVAC), can inhibit hemolysis in the storage of red blood cells (RBC). Study design and methods The effect of PVAC was assessed over a wide range of concentrations, using absorption spectroscopy to evaluate the level of hemolysis. Moreover, osmotic stability and aldehyde-scavenging potential of RBC were assessed after storage in PVAC. Results After test tube storage for two weeks, red blood cell hemolysis was lower with PVAC compared to controls (mean difference 23%, 95% CI 16-29%, p < 0.001). A higher level of hemolysis led to a pronounced effect with PVAC. RBC stored in PVAC improved both the binding of free aldehydes (p <0.001) and the osmotic stability (p = 0.0036). Conclusion Erythrocytes stored with PVAC showed less hemolysis, which might be explained by the ability of PVACs to stabilize the cell membrane and decrease oxidative injury.

Carbazate groups were grafted on the commercial cellulose membrane (CM) to specifically scavenge the carbonylated proteins for hemodialysis. It confirmed that carbazate groups were successfully covalently attached on the CMs by XPS and EDS, and the modified CMs still saved their original morphology and crystalline structures by SEM and XRD. Furthermore, the modified CMs presented favorable physicochemical stability at wide pH range from 2.5 to 7.4. It was also found that the carbazate modified CMs could selectively remove carbonylated proteins from acrolein treated bovine serum albumin (BSA) or ESRD patient's blood serum in PBS buffer. The modified CMs showed the potential to be utilized as the substitute of dialysis membranes in hemodialysis.

A series of biocompatible and non- toxic polysaccharide molecules have been successfully fabricated and explored their potential application for scavenging the carbonyl species in vitro. These macromolecules were dextrans with different hydrazide substitution ratios determined by TNBS assay, NMR and FTIR characterization. The colorimetric assay had demonstrated that these macromolecules could effectively scavenge acrolein, oxidized bovine serum albumin (BSA) in buffer solutions as well as carbonyl proteins from serum. The scavengers could achieve twice more scavenging effects for modified dextrans with high molecular weight (Mw=100,000) than those of low ones (Mw=40,000) with the same substitution ratio. Protein gel electrophoresis confirmed that the formation of the complex between carbonyls and modified dextrans resulted in appearance of slower bands. It also revealed that such macromolecules could protect cultured cells against the toxicity of acrolein or its derivatives. The proposed macromolecules indicated a very promising capability as scavengers for oxidative stress plus its derivatives without side effects.

Alternative solid polymer electrolytes (SPEs) hosts to the archetype poly(ethylene oxide) are gaining attention thanks to their appealing properties, such as higher cation transport number, thermal ...

Electrolytes comprising poly(ethylene carbonate) (PEC)/poly(trimethylene carbonate) (PTM C) with lithium bis(trifluoromethane sulfonyl)imide (LiTFSI) are prepared by a simple solvent casting method. Although PEC and PTMC have similar chemical structures, they are immiscible and two glass transitions are present in the differential scanning calorimetry (DSC) measurements. Interestingly, these two polymers change to miscible blends with the addition of LiTFSI, and the ionic conductivity increases with increasing lithium salt concentration. The optimum composition of the blend electrolyte is achieved at PEC6 PTMC4 , with a conductivity as high as 10-6 S cm-1 at 50 °C. This value is greater than that for single PEC- and PTMC-based electrolytes. Moreover, the thermal stability of the blend-based electrolytes is improved as compared to PEC-based electrolytes. It is clear that the interaction between CO groups and Li+ gives rise to a compatible amorphous phase of PEC and PTMC.

Three different polymers were synthesized and evaluated as solid polymer electrolytes: poly(ε-caprolactone) (PCL), polystyrene-poly(ε-caprolactone) (SC), and polystyrene-poly(ε-caprolactone-r-trimethylene carbonate) (SCT).

A triblock copolymer of benzyl methacrylate and oligo(ethylene glycol) methyl ether methacrylate was polymerized to form the general structure PBnMA-POEGMA-PBnMA, using atom transfer radical polymerization (ATRP). The block copolymer (BCP) was blended with lithium bis(trifluoro methylsulfonate) (LiTESI) to form solid polymer electrolytes (SPEs). AC impedance spectroscopy was used to study the ionic conductivity of the SPE series in the temperature interval 30 degrees C to 90 degrees C. Small-angle X-ray scattering (SAXS) was used to study the morphology of the electrolytes in the temperature interval 30 degrees C to 150 degrees C. By using benzyl methacrylate as a mechanical block it was possible to tune the microphase separation by the addition of LiTESI, as proven by SAXS. By doing so the ionic conductivity increased to values higher than ones measured on a methyl methacrylate triblocic copolymer-based electrolyte in the mixed state, which was investigated in an earlier paper by our group. A Li vertical bar SPE vertical bar LiFePO4 half-cell was constructed and cycled at 60 degrees C. The cell produced a discharge capacity of about 100 mAh g(-1) of LiFePO4 at C/10, and the half-cell cycled for more than 140 cycles.

The bulk of the scientific literature on Li-conducting solid (solvent-free) polymer electrolytes (SPEs) for applications such as Li-based batteries is focused on polyether-based materials, not least the archetypal poly(ethylene oxide) (PEO). A significant number of alternative polymer hosts have, however, been explored over the years, encompassing materials such as polycarbonates, polyesters, polynitriles, polyalcohols and polyamines. These display fundamentally different properties to those of polyethers, and might therefore be able to resolve the key issues restricting SPEs from realizing their full potential, for example in terms of ionic conductivity, chemical or electrochemical stability and temperature sensitivity. It is further interesting that many of these polymer materials complex Li ions less strongly than PEO and facilitate ion transport through different mechanisms than polyethers, which is likely critical for true advancement in the area. In this review, >30 years of research on these ‘alternative’ Li-ion-conducting SPE host materials are summarized and discussed in the perspective of their potential application in electrochemical devices, with a clear focus on Li batteries. Key challenges and strategies forward and beyond the current PEO-based paradigm are highlighted.

We report here a water-based functional binder framework for the lithium-sulfur battery systems, based on the general combination of a polyether and an amide-containing polymer. These binders are applied to positive electrodes optimised towards high-energy electrochemical performance based only on commercially available materials. Electrodes with up to 4 mAhcm(-2) capacity and 97-98% coulombic efficiency are achievable in electrodes with a 65% total sulfur content and a poly(ethylene oxide): poly(vinylpyrrolidone) (PEO: PVP) binder system. Exchange of either binder component for a different polymer with similar functionality preserves the high capacity and coulombic efficiency. The improvement in coulombic efficiency from the inclusion of the coordinating amide group was also observed in electrodes where pyrrolidone moieties were covalently grafted to the carbon black, indicating the role of this functionality in facilitating polysulfide adsorption to the electrode surface. The mechanical properties of the electrodes appear not to significantly influence sulfur utilisation or coulombic efficiency in the short term but rather determine retention of these properties over extended cycling. These results demonstrate the robustness of this very straightforward approach, as well as the considerable scope for designing binder materials with targeted properties.

BACKGROUND:Intraperitoneal adhesions cause significant morbidity. They occur after peritoneal trauma, which induces oxidative stress with production of inflammatory cytokines, peroxidized proteins (carbonyls) and lipids (aldehydes). This study aimed to investigate if carbazate-activated polyvinyl alcohol (PVAC), an aldehyde-carbonyl inhibitor, can reduce intraperitoneal adhesions in an experimental model. MATERIAL AND METHODS:Male Sprague-Dawley rats (n=110) underwent laparotomy, cecal abrasion and construction of a small bowel anastomosis. They either were treated with intraperitoneal instillation of PVAC or were sutured with PVAC-impregnated sutures. Thromboelastography analysis was performed using human blood and PVAC. The lipid peroxidation product malondialdehyde (MDA) and inflammatory cytokines IL-1β and IL-6 were quantified in peritoneal fluid. At day 7, bursting pressure of the anastomosis was measured and adhesions were blindly scored. RESULTS:PVAC in human blood decreased the production of the fibrin-thrombocyte mesh without affecting the coagulation cascade. MDA, IL-1β and IL-6 were increased after 6h without significant difference between the groups. PVAC-impregnated sutures reduced intraperitoneal adhesions compared to controls (p=0.0406) while intraperitoneal instillation of PVAC had no effect. Anastomotic bursting pressure was unchanged. CONCLUSIONS:Intervention with an aldehyde-carbonyl inhibitor locally in the wound by PVAC-impregnated sutures might be a new strategy to reduce intraperitoneal adhesions.

A series of deuterated tri-block copolymers with the general structure d(8)-PMMA-POEGMA-d(8)-PMMA, with variation in d(8)-PMMA chain length, were synthesized using sequential controlled radical polymerization (ATRP). Solid polymer electrolytes (SPEs) were produced by blending tri-block copolymers and lithium bis(trifluoro methylsulfonate) (LiTFSI). Small-angle neutron scattering (SANS) was used to study the bulk morphology of the deuterated tri-block copolymer electrolyte series at 25 degrees C, 60 degrees C and 95 degrees C. The lack of a second T-g in DSC analysis together with modelling with the random phase approximation model (RPA) confirmed that the electrolytes are in the mixed state, with negative Flory-Huggins interaction parameters. AC impedance spectroscopy was used to study the ionic conductivity of the SPE series in the temperature interval 30 degrees C-90 degrees C, and a battery device was constructed to evaluate a 25 wt% d(8)-PMMA electrolyte. The Li | SPE | LiFePO4 cell cycled at 60 degrees C, giving a discharge capacity of 120 mAh g(-1), while cyclic voltammetry showed that the SPE was stable at 60 degrees C. (C) 2017 Elsevier Ltd. All rights reserved.

Poly(vinyl alcohol) (PVA) has, to a limited degree, previously been investigated as an alternative host material to the dominating poly(ethylene oxide)-(PEO)-based polymer electrolytes used in electrochemical applications. These PVA-materials were found to be highly ionically conducting for a number of different salts at temperatures below the glass transition temperature, but in the presence of DMSO (dimethyl sulfoxide) residues. Here, we investigate the PVA:LiTFSI (lithium bis(triflouromethane)sulfonamide) electrolytes system, thereby for the first time using the salt most commonly explored in PEO-based systems also in PVA. It is shown that this results in significantly higher conductivities than for alternative Li salts. Comparisons between electrolytes casted in DMSO, H2O and hot-pressed samples confirm the necessity of solvent residues present in the DMSO casted films for the ionic transport, although no obvious liquid phase is formed. Moreover, we also show the feasibility of PVA-based electrolytes by construction of functional Li-metal | PVA-LiTFSI (DMSO) | LiFePO4 batteries operating at 60°C, displaying stable capacities of 136mAh/g LiFePO4 at a rate of C/20.

The microenvironment around a cell critically determines its function and behavior. Nanometer scale topographic and chemical structures can provide cues and organization signals imposing a pattern on the extracellular matrix molecules adsorbing to nanostructured materials. Here a route to define cell instructive nanostructured interfaces based on colloidal monolayer masks and traditional lithographic steps will be described. Dispersed monolayers resulting from sequential electrostatic binding to oppositely charged surfaces results in short range ordered arrays of particles and can be utilized to generate one nanostructure per particle. The generated patterns have no long range order and are homogeneous over large areas (10’s of cm) and can be chemically functionalized to enable protein patterning. These materials are used to pattern specific ECM and cell-cell adhesion molecules for use in understanding and steering development and signaling at adhesive complexes such as integrin based focal adhesions and cadherin based adherence junctions. Examples of studies with different ECM protein patterns (e.g. Fibronectin [1], Vitronectin [2], Laminin, Collagen,) and cellcell adhesion proteins (e.g. E-Cadherin [3] and ICAM) and their influence on cell adhesion and differentiation will be given. Both the size scale of the protein patches and the specific proteins immobilized are critical to determining and steering the cellular response. The size scale of the patterns in the range 60-3000 nm systematically controls the cellular attachment but with different critical sizes in specific systems. A clear role and importance for the specific ligand pattern was observed with nanopatterns of fibronectin and vitronectin showing clear differences in the mechanism of adhesion [2]. Colloidal lithographic techniques represent a useful tool for use in the study of the mechanics of cellular adhesion and control of differentiation.

In the present work, a photopolymerized urethane-based poly(ethylene glycol) hydrogel is applied as a porous scaffold material using indirect solid freeform fabrication (SFF). This approach combines the benefits of SFF with a large freedom in material selection and applicable concentration ranges. A sacrificial 3D poly(ε-caprolactone) structure is generated using fused deposition modeling and used as template to produce hydrogel scaffolds. By changing the template plotting parameters, the scaffold channel sizes vary from 280 to 360 μm, and the strut diameters from 340 to 400 μm. This enables the production of scaffolds with tunable mechanical properties, characterized by an average hardness ranging from 9 to 43 N and from 1 to 6 N for dry and hydrated scaffolds, respectively. Experiments using mouse calvaria preosteoblasts indicate that a gelatin methacrylamide coating of the scaffolds results in an increased cell adhesion and proliferation with improved cell morphology.