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Levulinic acid(LA) is produced through acid-catalyzed hydrolysis and dehydration of lignocellulosic biomass. It is a key platform chemical used as an intermediate in various industries including biofuels, cosmetics, pharmaceuticals, and polymers. Traditional LA production uses chemical conversion, which requires high temperatures and pressures, strong acids, and produces undesirable side reactions, repolymerization products, and waste problems Therefore, we designed an integrated process to produce LA from glucose through metabolic engineering of Pseudomonas putida KT2440. As a metabolic engineering strategy, codon optimized phospho-2-dehydro-3-deoxyheptonate aldolase (AroG), 3-dehydroshikimate dehydratase (AsbF), and acetoacetate decarboxylase (Adc) were introduced to express genes of the shikimate and β-ketoadipic acid pathways, and the 3-oxoadipate CoA-transferase (pcaIJ) gene was deleted to prevent loss of biosynthetic intermediates. To increase the accumulation of the produced LA, the lva operon encoding levulinyl-CoA synthetase (LvaE) was deleted resulting in the high LA-producing strain P. putida HP203. Culture conditions such as medium, temperature, glucose concentration, and nitrogen source were optimized, and under optimal conditions, P. putida HP203 strain biosynthesized 36.3 mM (4.2 g/L) LA from glucose in a fed-batch fermentation system. When lignocellulosic biomass hydrolysate was used as the substrate, this strain produced 7.31 mM of LA. This is the first report of microbial production of LA from glucose by P. putida. This study suggests the possibility of manipulating biosynthetic pathway to produce biological products from glucose for various applications. • A strategy to produce levulinic acid from glucose was developed in P. putida KT2440. • Introducing aroG , asbF , and adc genes enabled levulinic acid production from glucose. • Deleting the pcaIJ and lvaE genes increased levulinic acid production in P. putida. • A levulinic acid yield of 36.3 mM (4.2 g/L) was achieved in fed-batch fermentation. • This is the first report of microbial levulinic acid production from glucose. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of adding cholesteryl methacrylate (CM) monomer to experimental composite resins and evaluate its impact on polymerization shrinkage force (PSF), Knoop microhardness (KHN), sorption and solubility (SS), vulnerability to spontaneous oxidation (VOE), porosity (BES), viscosity (V), and cross-link density (CLD). CM was synthesized, mixed with varying proportions of Bis-GMA, 70 wt% filler particles, and 40 % TEGDMA. The groups tested were: CM0 (60 % Bis-GMA), CM6 (54 % Bis-GMA/6 % CM), CM12 (48 % Bis-GMA/12 % CM), CM18 (42 % Bis-GMA/18 % CM) and CM24 (36 % Bis-GMA/24 % CM). The PSF was evaluated using a universal testing machine. KHN was measured with a 50 g load for 30 s. SS was determined according to ISO 4049:2009. VOE was measured with a three-electrode system in an electrochemical cell. BES images were obtained using an electron microscope to assess porosity. Viscosity was measured through rheological analysis. CLD was estimated from hardness readings before and after ethanol storage. CM6 (0.34 N) and CM12 (0.34 N) exhibited the lowest PSF values compared to CM0 (0.91 N). For KHN, CM6 (32.03) and CM12 (31.03) had higher values than CM0 (25.83) and were similar to CM18 (29.39) and CM24 (28.64). SS showed no significant differences among the groups. VOE indicated low vulnerability across all groups. CM12 had greater porosity compared to CM0 in BES images. CM0 had the lowest viscosity among the groups. No differences in CLD were observed among CM0, CM12, CM18, and CM24 regarding softening effects. Adding CM to Bis-GMA/TEGDMA composite resins can reduce polymerization shrinkage force and increase the initial Knoop microhardness without affecting the other properties studied. • Cholesteryl methacrylate proved to be a promising polymer for improving composites. • An endocyclic double bond can be an additional site for photochemical cycloaddition. • Its endocyclic double bond can form adducts with other monomers. • Concentrations of 6 % and 12 % of cholesteryl methacrylate promoted better performance. • Initial microhardness and polymerization shrinkage force showed improved results. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the degree of conversion (%), flexural strength (MPa), elastic modulus (GPa), compressive strength (MPa), Knoop microhardness (KHN), post-gel shrinkage (%) and prediction of ideal concentration of cholesteryl methacrylate (CM) in experimental resins. Four formulations were manipulated (F): F1, control group, (0 % CM); F2 (15 % CM); F3 (19.8 % CM) and F4 (30 % CM). Bis-GMA and CM percentages were determined using Statistica™ software. For the degree of conversion test, Raman spectroscopy was used. To testing flexural strength, elastic modulus and compressive strength, a universal testing machine was used. For the Knoop microhardness test five indentations were made in each sample. Post-gel shrinkage was determined using the strain gauge method. Statistica™ software processed all data obtained in this study. Results were submitted to one-way ANOVA and Tukey's post hoc tests (α = 0.05). Better performance was observed for F2 (15 % CM) and F3 (19,8 % CM) for degree of conversion, elastic modulus and post-gel shrinkage. For Knoop microhardness F2 (15 % CM), F3 (19,8 % CM) and F4 (30 % CM) showed higher values than F1 (0 % CM). For flexural strength F1 (0 % CM) and F3 (19,8 %) were similar and F4 showed the lowest values and for compressive strength F1 (0 % CM) showed the highest values. For mixture designs analysis data, concentrations ≤ 25 % of CM would provide better results. Addition of CM at concentrations lower than 30 % contributed to a significant increase in the degree of conversion, microhardness values, elastic modulus and reduction of post-gel shrinkage. • Cholesteryl methacrylate proved to be a promising polymer for improving composites. • An endocyclic double bond can be an additional site for photochemical cycloaddition. • Concentrations ≤ 25 % cholesteryl methacrylate enhance composite resins. • Post-gel shrinkage performed better with 15 %, 19.8 % and 30 % cholesteryl methacrylate. • Knoop microhardness was higher with 15 %, 19.8 %, and 30 % cholesteryl methacrylate. [ABSTRACT FROM AUTHOR]

Lactose intolerance affects ∼65% of the global adult population, leading to the demand for lactose-free products. The enzyme β-galactosidase (βG) is commonly used in the industry to produce such products, but its recovery after lactose hydrolysis is challenging. In this scenario, the study aims to encapsulate βG within capsules, varying in dimensions and wall materials, to ensure their suitability for efficient industrial recovery. The enzyme βG was encapsulated through ionic gelation using alginate and its blends with pectin, maltodextrin, starch, or whey protein as wall materials. The capsules produced underwent evaluation for encapsulation efficiency, release profiles, activity of the βG enzyme, and the decline in enzyme activity when reused over multiple cycles. Alginate at 5% wt/vol concentrations, alone or combined with polymers such as maltodextrin, starch, or whey protein, achieved encapsulation efficiencies of ∼98%, 98%, 80%, and 88%, respectively. The corresponding enzyme recovery rates were 34%, 19%, 31%, and 48%. Capsules made with an alginate-pectin blend exhibited no significant hydrolysis and maintained an encapsulation efficiency of 79%. Encapsulation with alginate alone demonstrated on poor retention of enzyme activity, showing a loss of 74% after just 4 cycles of reuse. Conversely, when alginate was mixed with starch or whey protein concentrate, the loss of enzyme activity was less than 40% after 4 reuses. These results highlight the benefits of combining encapsulation materials to improve enzyme recovery and reuse, offering potential economic advantages for the dairy industry. The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. [ABSTRACT FROM AUTHOR]

The non-equilibrium structural and dynamical properties of a flexible polymer tethered to a reflecting wall and subject to oscillatory linear flow are studied by numerical simulations. Polymer is confined in two dimensions and is modeled as a bead-spring chain immersed in a fluid described by the Brownian multiparticle collision dynamics. At high strain, the polymer is stretched along the flow direction following the applied flow, then recoils at flow inversion before flipping and elongate again. When strain is reduced, it may happen that the chain recoils without flipping when the applied shear changes sign. Conformations are analyzed and compared to stiff polymers revealing more compact patterns at low strains and less stretched configurations at high strain. The dynamics is investigated by looking at the center-of-mass motion which shows a frequency doubling along the direction normal to the external flow. The center-of-mass correlation function is characterized by smaller amplitudes when reducing bending rigidity. • Presence of three conformational regimes when varying external strain. • Flexible chains are more compact at low strains and less stretched at high strains with respect to stiff polymers. • Smaller amplitudes in the center-of-mass autocorrelation function when reducing bending rigidity. [ABSTRACT FROM AUTHOR]

Oral biotherapeutics hold significant promise, but their lack of controllability and targeting poses a major challenge, particularly for intestinal bacterial biotherapeutics. In response, we have developed a nanoencapsulation approach that responds to the release of enzyme activity in the organism and activates the enzyme in situ, allowing for controlled colonization of microbes in the gut. The nano-coating comprises a two-layer structure: an inner layer of polydopamine with photothermal and adhesive properties, and an outer layer of gelatin–sodium carboxymethylcellulose, which is hydrolyzed by cellulases in the gut following photothermal interaction with dopamine. We have successfully achieved controlled colonization of a wide range of microorganisms. Furthermore, in a diabetes model, this approach has had a profound impact on regulating glucagon-like peptide-1 (GLP-1) production, β-cell physiology, and promoting insulin secretion. This nanocoating is achieved by in situ activation of cellulase without the need for genetic or targeted molecular modification, representing a new paradigm and alternative strategy for microbial therapy. It not only enables precise and controlled colonization of probiotics but also demonstrates great potential for broader application in the field of oral biotherapy. We have developed a nano-encapsulation method that triggers enzyme activity in response to enzymatic activity, resulting in the controlled release and adhesion of a wide range of microorganisms in the gut. The nano coating comprises two layers: an inner layer of polydopamine with photothermal and adhesion properties, and an outer layer of a gelatin-sodium carboxymethylcellulose polymer, which can be hydrolyzed by cellulases in the intestine. Additionally, this method allows for the preparation of various microbial coatings. This approach holds significant promise for regulating GLP-1 production, the physiological function of pancreatic β-cells, and promoting insulin secretion in diabetes models. [Display omitted] [ABSTRACT FROM AUTHOR]

An important aspect to consider in the evaluation of parts and assemblies by X-ray computed tomography (XCT) is the attenuation coefficient of the different materials involved, which are directly related to their density; depending on this coefficient, the X-ray penetration varies and, therefore, varies the contrast between different materials and with the background. This becomes more critical in those assemblies in which materials are characterized by a high difference in density, where the lighter material could be difficult to be characterised. In this paper, the effect of the presence of metals in the dimensional evaluation of polymeric geometries (having lower density than the metal parts) is studied, to evaluate the errors caused in dimensional measurements of different geometries and surface texture characterization. Based on a common geometry, four scenarios have been experimentally tested with variations of metal amount, in which macro geometries (precision spheres made by different polymers) and micro geometries (inclined ramps manufactured by fused deposition modelling (FDM)) have been characterised. Results show errors in the surface determination of the polymeric features directly related to the presence of metal: a high amount of steel makes significantly difficult to accurately determine the interface between background and material due to the noise and artifacts created, while aluminium has less influence on the irregularities of the features extracted. This effect is more evident for polymers with lower density due to the higher difference. Numerically, most affected parameters are those sensible to variations in surface determination, such as spheres' form error and ramps' maximum surface texture (Sz), while more solid features as spheres' diameters, distances and ramps' average surface texture (Sa and Sq) remain more stable. In conclusion and to sum up, it has been found that the quantity of metal present in assemblies made of polymeric and metallic materials is correlated with distortions in the dimensional evaluation of polymeric features by XCT. [ABSTRACT FROM AUTHOR]

Topical ophthalmic drug product development is a niche research domain as the drug formulations need to be designed to perform in the unique ocular physiological conditions. The most common array of small molecule drug formulations intended for topical ophthalmic administration include solutions, suspensions, emulsions, gels, and ointments. The formulation components such as excipients and container closure are unique to serve the needs of topical ophthalmic delivery compared to other parenteral products. The selection of appropriate formulation platform, excipients, and container closure for delivery of drugs by topical ophthalmic route is influenced by a combination of factors like physicochemical properties of the drug molecule, intended dose, pharmacological indication as well as the market trends influenced by the patient population. In this review, data from literature and packaging inserts of 118 reference listed topical ophthalmic medications marketed in the US are collected and analyzed to identify trends that would serve as a guidance for topical ophthalmic formulation development for small molecule drugs. Specifically, the topics reviewed include current landscape of the available small molecule topical ophthalmic drug products in the US, physicochemical properties of the active pharmaceutical ingredients (APIs), formulation platforms, excipients, and container closure systems. [Display omitted] [ABSTRACT FROM AUTHOR]

Inflammatory skin conditions highly influence the quality of life of the patients suffering from these disorders. Symptoms include red, itchy and painful skin lesions, which are visible to the rest of the world, causing stigmatization and a significantly lower mental health of the patients. Treatment options are often unsatisfactory, as they suffer from either low patient adherence or the risk of severe side effects. Considering this, there is a need for new treatments, and notably of new ways of delivering the drugs. Stimuli-responsive drug delivery systems are able to deliver their drug cargo in response to a given stimulus and are, thus, promising for the treatment of inflammatory skin conditions. For example, the use of external stimuli such as ultraviolet light, near infrared radiation, or alteration of magnetic field enables drug release to be precisely controlled in space and time. On the other hand, internal stimuli induced by the pathological condition, including pH alteration in the skin or upregulation of reactive oxygen species or enzymes, can be utilized to create drug delivery systems that specifically target the diseased skin to achieve a better efficacy and safety. In the latter context, however, it is of key importance to match the trigger mechanism of the drug delivery system to the actual pathological features of the specific skin condition. Hence, the focus of this article is placed not only on reviewing stimuli-responsive drug delivery systems developed to treat specific inflammatory skin conditions, but also on critically evaluating their efficacy in the context of specific skin diseases. Skin diseases affect one-third of the world's population, significantly lowering the quality of life of the patients, who deal with symptoms such as painful and itchy skin lesions, as well as stigmatization due to the visibility of their symptoms. Current treatments for inflammatory skin conditions are often hampered by low patient adherence or serious drug side effects. Therefore, more emphasis should be placed on developing innovative formulations that provide better efficacy and safety for patients. Stimuli-responsive drug delivery systems hold considerable promise in this regard, as they can deliver their cargo precisely where and when it is needed, reducing adverse effects and potentially offering better treatment outcomes. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] Chromatography–mass spectrometry of samples representing the interaction products of ferrocene, radical initiator and monomer taken in the molar ratio of 1:2:10 in toluene solution was used for experimental detection of products indicating the structure and mechanism of formation of metal complex active centers of radical-coordination polymerization. Structures similar to those proposed by the quantum-chemical modeling were demonstrated to be formed with the participation of secondary radicals. [ABSTRACT FROM AUTHOR]

Nano-bienzyme conjugates (nano-BECs) for catalysing one-pot reactions can simplify the reaction process and improve the efficiency of biocatalytic reactions. In this work glucose dehydrogenase (GDH) and Candida parapsilosis secondary alcohol dehydrogenase (CpSADH) were immobilised with polyacrylic acid (PAA) to form two types of PAA-based nano-BECs (2-S, 2-P), which achieved in situ regeneration of NADH for the production of chiral alcohols in oil-water biphasic systems, such as the key chiral pharmaceutical intermediate of (S)-1-(3-trifluoromethylphenyl)ethanol ((S)-TMPE). At a substrate concentration of 100 mM 3-trifluoromethylacetophenone (TMAP), the conversion catalyzed by nano BEC was 98.2 % in dipentyl phthalate-phosphate buffer biphasic system. In contrast, the conversion was only 39.5 % and 38.9 % in the PB buffer and 8.4 % and 7.7 % in dipentyl phthalate system. The experiments on kinetic constants demonstrated that the catalytic efficiencies (K cat /K m) of nano-BECs (2-S, 2-P) were enhanced by 6.7-fold and 7-fold, respectively, compared to free CpSADH. Additionally, nano-BECs showed stronger coenzyme regeneration ability. Under optimal reaction conditions, nano-BECs achieved 96.2 % conversion of TMAP to (S)-TMPE in an organic-buffer system with e.e. > 99.6 % at 300 mM substrate concentration. This research expands the potential applications of polymers and proteins, and offers valuable insights into the synergistic effects of PAA on bienzyme catalytic systems in biocatalysis. [Display omitted] • Heterologous expression of Candida parapsilosis secondary alcohol dehydrogenase (CpSADH). • Co-immobilization of glucose dehydrogenase (GDH) and CpSADH to form nano-polymers. • One-pot efficient catalytic carbonyl asymmetric reduction by nano-polymers. • Preparation of (S)-1-(3-trifluoromethylphenyl)ethanol at high substrate concentration. [ABSTRACT FROM AUTHOR]

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We report the synthesis of a novel class of metal-complexing peptide-based polymers, which we name HyperMAPs (Hyper -loaded M et A l-complexed P olymers). The controlled solid-phase synthesis of HyperMAPs' scaffold peptide provides our polymer with a well-defined molecular structure that allows for an accurate on-design assembly of a wide variety of metals. The peptide-scaffold features a handle for direct conjugation to antibodies or any other biomolecules by means of a thiol-maleimide-click or aldehyde-oxime reaction, a fluorogenic moiety for biomolecule conjugation tracking, and a well-defined number of functional groups for direct incorporation of metal-chelator complexes. Since metal-chelator complexes are prepared in a separate reaction prior to incorporation to the peptide scaffold, polymers can be designed to contain specific ratios of metal isotopes, providing each polymer with a unique CyTOF spectral fingerprint. We demonstrate the complexing of 21 different metals using two different chelators and provide evidence of the application of HyperMAPs on a 13 parameter CyTOF panel and compare its performance to monoisotopic metal-conjugated antibodies. • Current metal chelating polymers for use in mass cytometry design limits amount of metals. • Complexing metals to chelators before attachment to a scaffold provides better quality control. • Our design enables 21 metals and demonstrates similar signal to current polymers. • Spectral deconvolution of multi-isotopic signal is shown, enabling combining isotopes per marker. [ABSTRACT FROM AUTHOR]

Resistance to antibiotics such as Ciprofloxacin (CIP) is becoming a critical issue and needs to be addressed globally. CIP is widely used because of manifold uses; however, the long-term therapy poses serious health risks including FDA black box warnings such as tendinitis and peripheral neuropathy. Therefore, nanotechnology-based products can be an effective measure to improve therapeutic outcomes by maintaining the dose at the target site while reducing the dose-dependent toxicity. Biodegradable and biocompatible polymers, Chitosan (CS) and Hyaluronic acid (HA) were used in this work due to their diverse biological characteristics. A simple yet economical ionic gelation method was employed to synthesize nanoparticles with a plexus-like network; nanoplexes, followed by spray-drying to obtain the dry powders to improve stability. Quality by Design (QbD) approach was utilized during the study for robustness and standardization followed by Design of Experiment (DoE) for optimization in a holistic way. The mean particle size of the optimized powder sample was found to be 301.1 nm with a percentage encapsulation efficiency (% EE) of 78.8%. In-vitro dissolution studies corroborated the controlled release of CIP over 48 h. Also, mathematical kinetic modeling was applied to obtain thorough insight into the mechanism of drug release. Moreover, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were presented to be lower in the case of prepared dry powder as compared to CIP, stating that nanotechnology can improve antimicrobial activity. [Display omitted] [ABSTRACT FROM AUTHOR]

Composites with copper-doped mesoporous bioactive nanospheres (Cu-MBGN) were developed to prevent secondary caries by imparting antimicrobial and ion-releasing/remineralizing properties. Seven experimental composites containing 1, 5 or 10 wt% Cu-MBGN, the corresponding inert controls (silica) and bioactive controls (bioactive glass 45S5) were prepared. The temperature rise during light curing, cross-linking density by ethanol softening test, monomer elution and their potential adverse effects on the early development of zebrafish Danio rerio was investigated. Materials combining Cu-MBGN and silica showed the highest resistance to ethanol softening, as did the bioactive controls. Cu-MBGN composites showed significant temperature rise and reached maximum temperature in the shortest time. Bisphenol A was not detected, while bis-GMA was found only in the control materials and TEGDMA in the eluates of all materials. There was no increase in zebrafish mortality and abnormality rates during exposure to the eluates of any of the materials. The composite with 5 wt% Cu-MBGN combined with nanosilica fillers showed the lowest ethanol softening, indicating the polymer's highest durability and cross-linking density. Despite the TEGDMA released from all tested materials, no embryotoxic effect was observed. [Display omitted] • composites with copper-doped mesoporous bioactive nanospheres were developed. • high and rapid rise in temperature occurred during polymerisation. • cross-linking density of polymer network did not correlate with monomer release. • only triethylene glycol dimethacrylate was released during 7 days in ethanol. • did not cause embryotoxicity or abnormalities in Danio rerio. [ABSTRACT FROM AUTHOR]

Immobilized lipases are biotechnological spotlights as tools to improve and enhance enzyme applicability. Here, lipase from Rhizomucor miehei (RML) was immobilized onto core/shell supports, named poly(methyl methacrylate) (PMMA/PMMA); poly(methyl methacrylate) copolymerized with divinylbenzene (PMMA- co -DVB/PMMA- co -DVB); and polystyrene copolymerized with divinylbenzene (PS- co -DVB/PS- co -DVB), and on a commercial non-core/shell porous support (polypropylene - Accurel MP 1000). Different enzyme loadings were evaluated (400 U.g−1, 500 U.g−1, 600 U.g−1, 4000 U.g−1, and 6000 U.g−1), and the immobilized biocatalysts were used in hydrolysis (using p -nitrophenyl laurate (p -NPL) and p -nitrophenyl butyrate (p -NPB) as substrates) and in esterification reactions (using oleic acid and ethanol as substrates). The influence of pH, temperature, and buffer concentration in the hydrolysis of p -NPL was also investigated. The immobilized biocatalysts were compared to free RML and/or to commercially immobilized RML (RM-IM) and/or to Novozym 435. RML interacted differently with each support, being RML-PMMA- co -DVB/PMMA- co -DVB and RML-PMMA/PMMA the biocatalysts with the highest enzymatic activities (hydrolytic activity: >400 U.g−1, using p -NPL; esterification activity: 25,532 U.g−1). Immobilization improved the thermal and pH tolerance and buffer concentration tolerance of RML. Both free RML and the immobilized biocatalysts exhibited their maximum activity at pH 7, with the exception of RML-Accurel MP 1000, which displayed optimal performance at pH 9.0. In addition, RML-PS- co -DVB/PS- co -DVB demonstrated increased activity at 70 °C. Notably, RML-PMMA/PMMA and RML-PMMA- co -DVB/PMMA- co -DVB showcased a maximum activity of 120 U/g, and this was achieved at different temperatures, 30°C and 50°C, respectively. This diverse library of immobilized biocatalysts shows promising potential for application in various industrial processes. [Display omitted] • RML was immobilized onto four home-made hydrophobic supports. • The properties of RML biocatalysts were modulated by the immobilization conditions. • The esterification performance surpassed RM-IM and Novozym 435. • The optimal conditions to RML biocatalysts depend of the support used. [ABSTRACT FROM AUTHOR]

The microstructural evolution of C sf /SiBCN composites and formation mechanism of the oxide layer after oxidation for 1–10 h at 1500 ℃ were studied. As the oxidation time increases to 10 h, the macrostructure of the porous C sf /MA-SiBCN composite collapses obviously, while the C sf /SiBCN composite densified via the polymer infiltration and pyrolysis (PIP) process maintains structural integrity due to the formation of the oxide layer with a tri-layer structure: the outermost loose layer mainly containing cristobalite, the dense interlayer of amorphous glass and the innermost layer of some unoxidized BN(C) and SiC grains embedded into the amorphous glass, which hinders the diffusion of oxygen. [ABSTRACT FROM AUTHOR]

Poly(ethylene glycol) (PEG) is widely utilized as a hydrophilic coating to extend the circulation time and improve the tumor accumulation of polymeric micelles. Nonetheless, PEGylated micelles often activate complement proteins, leading to accelerated blood clearance and negatively impacting drug efficacy and safety. Here, we have crafted amphiphilic block copolymers that merge hydrophilic sulfoxide-containing polymers (psulfoxides) with the hydrophobic drug 7-ethyl-10-hydroxylcamptothecin (SN38) into drug-conjugate micelles. Our findings show that the specific variant, PMSEA-PSN38 micelles, remarkably reduce protein fouling, prolong blood circulation, and improve intratumoral accumulation, culminating in significantly increased anti-cancer efficacy compared with PEG-PSN38 counterpart. Additionally, PMSEA-PSN38 micelles effectively inhibit complement activation, mitigate leukocyte uptake, and attenuate hyperactivation of inflammatory cells, diminishing their ability to stimulate tumor metastasis and cause inflammation. As a result, PMSEA-PSN38 micelles show exceptional promise in the realm of anti-metastasis and significantly abate SN38-induced intestinal toxicity. This study underscores the promising role of psulfoxides as viable PEG substitutes in the design of polymeric micelles for efficacious anti-cancer drug delivery. This study emphasizes PMSEA's potential as a sulfoxide-containing polymer for anti-cancer drug delivery, offering an alternative to PEG in constructing polymeric prodrug micelles efficiently. [Display omitted] • Sulfoxide-containing polymer PMeSEA presents a promising alternative to PEG. • Micelles grafted with PMeSEA successfully diminish complement system activation. • Reducing complement activation enhances the antitumor activity of PMeSEA-micelles. [ABSTRACT FROM AUTHOR]

This study analysed the formation of biofilms in the drinking water distribution system in Wroclaw. The focus was on the influence of the material from which pipes in water distribution systems are built: polyethylene (PE) and polypropylene (PP). Two reactors with continuous water flow were used. Once the quasi- steady state was determined, an analysis was carried out to measure the total number of microorganisms per unit volume, which were stabilised without affecting further changes in concentration, and to study the basic physicochemical parameters of water that can affect the microbial growth that forms. In addition, a literature review was conducted to analyse biofilm formation based on physicochemical parameters in the water distribution system. Psychrophilic bacteria were shown to be more numerous than mesophilic bacteria, with the growth rate of the latter being higher. An increase in the number of microorganisms was observed, with higher concentrations found on PE surfaces because the rougher surface structure provides better adhesion for biofilm-forming microorganisms than on a surface made of polypropylene (PP). The presence of mesophilic bacteria may indicate the potential for pathogenic microorganisms, as well as the formation of a primary biofilm characterised by irreversible attachment to the substrate. These findings suggest that synthetic materials such as PE are more susceptible to biological growth than polypropylene (PP) as a result of their uneven surface structure, which facilitates the deposition of biofilm-forming organisms. The preliminary results can be used as an important reference for future research related to biofilms in drinking water distribution systems. [ABSTRACT FROM AUTHOR]

[Display omitted] A method for assessing the synthesis complexity of in silico designed polymers using the modified Synthetic Accessibility Score Index is presented. This index is calculated by decomposing a chemical structure into smaller fragments and evaluating their contribution to the overall score. Also discussed are the data sources for these estimates, ways to overcome ambiguity in the representation of the smallest repeating unit of polymers, and the problem of evaluating the stability of chemical structures stored in machine- generated databases. [ABSTRACT FROM AUTHOR]

Decreasing gas penetration has noticeable effects on the durability and performance of Nafion based proton exchange membranes (PEMs). Experimental studies showed that adding imidazolyl groups into Nafion could reduce the hydrogen permeation in the membrane, while causing the substantial increase in power density. Nonetheless, the microscopic mechanism of doping on the reduction of hydrogen permeation is remain unclear. In this work, molecular dynamics simulation was performed to understand the transport behaviors of hydrogen in polyvinylimidazole (PVMZ)/Nafion composite membranes at the molecular level. The simulation results indicate that there are different degrees of effects about the polymer phase and aqueous domain on the diffusion kinetics of hydrogen in Nafion and PVMZ/Nafion at low and high hydration levels. With the increase of water content, the hydrogen molecules will migrate from the polymer phase to the polymer/water interface in Nafion and PVMZ/Nafion membranes. At low water content, the more free volume and the more pores in Nafion membrane are conducive to the diffusion of hydrogen than that in PVMZ/Nafion membrane to a greater extent. For the aqueous domain, the smaller and the rougher surface of water clusters in PVMZ/Nafion membranes have a certain limiting effect on the diffusion of hydrogen molecules than that in Nafion membranes at high water content. Consequently, at low water contents (λ ≤ 9), the self-diffusion coefficient of hydrogen (D H2) increases slowly from 0.55 to 1.01 (× 10−5 cm2/s) in Nafion membrane and from 0.26 to 0.53 (× 10−5 cm2/s) in PVMZ/Nafion membrane. In contrast, at high water contents (λ ≥ 9), the D H2 increases rapidly from 1.01 to 2.35 (× 10−5 cm2/s) in Nafion membranes and from 0.53 to 1.74 (× 10−5 cm2/s) in PVMZ/Nafion membranes. The current work can provide a fundamental understanding for experimentally designing new type Nafion based PEMs for hydrogen fuel cells. [Display omitted] • A similar but lower diffusion of hydrogen occurs in PVMZ/Nafion than Nafion under different water contents. • There are different effects for polymer phase and aqueous domain on the diffusion kinetics of hydrogen in Nafion and PVMZ/Nafion. • The hydrogen in Nafion and PVMZ/Nafion tends to migrate toward the polymer/water interface as increasing water content. [ABSTRACT FROM AUTHOR]

[Display omitted] Traditional dual-ion lithium salts have been widely used in solid polymer lithium-metal batteries (LMBs). Nevertheless, concentration polarization caused by uncontrolled migration of free anions has severely caused the growth of lithium dendrites. Although single-ion conductor polymers (SICP) have been developed to reduce concentration polarization, the poor ionic conductivity caused by low carrier concentration limits their application. Herein, a dual-salt quasi-solid polymer electrolyte (QSPE), containing the SICP network as a salt and traditional dual-ion lithium salt, is designed for retarding the movement of free anions and simultaneously providing sufficient effective carriers to alleviate concentration polarization. The dual salt network of this designed QSPE is prepared through in-situ crosslinking copolymerization of SICP monomer, regular ionic conductor, crosslinker with the presence of the dual-ion lithium salt, delivering a high lithium-ion transference number (0.75) and satisfactory ionic conductivity (1.16 × 10−3 S cm−1 at 30 °C). Comprehensive characterizations combined with theoretical calculation demonstrate that polyanions from SICP exerts a potential repulsive effect on the transport of free anions to reduce concentration polarization inhibiting lithium dendrites. As a consequence, the Li||LiFePO 4 cell achieves a long-cycle stability for 2000 cycles and a 90% capacity retention at 30 °C. This work provides a new perspective for reducing concentration polarization and simultaneously enabling enough lithium-ions migration for high-performance polymer LMBs. [ABSTRACT FROM AUTHOR]

Two- and tree-component spinel-polymer composites were produced by thermal pressing. The initial components were chosen as CoFe 2 O 4 and Ni 0.4 Cu 0.2 Zn 0.4 Fe 2 O 4 spinels that were produced using the sol-gel method. The ratio between spinel phases varied from 1:3 to 3:1. As a polymer, fluorinated ethylene propylene was used. The concentration of the spinels in the polymer matrix was fixed at 20 mass.%. Using XRD, SEM, and high-frequency spectroscopy, the correlation between the composition, structure, and electrodynamic characteristics of composites was established. It was found that the parameters of the unit cell of ferrite fillers do not change when filling the polymer. The RL values for the initial CoFe 2 O 4 /FEP and Ni 0.4 Cu 0.2 Zn 0.4 Fe 2 O 4 /FEP were in the range of −14.5 ... -24.2 dB and −10.4 ... -14.1 dB, respectively, which is lower than for ferrites without a polymer matrix. The maximum values of RL (as a module) were marked for CoFe 2 O 4 /FEP. Obtained values of the reflection loss coefficient in the range of 5–10 GHz open broad perspectives for the development of materials for electromagnetic absorption and 5G technology. [ABSTRACT FROM AUTHOR]

Highly crystalline carbon nitride polymers have shown great opportunities in overall water photosplitting; however, their mission in light-driven CO 2 conversion remains to be explored. In this work, crystalline carbon nitride (CCN) nanosheets of poly triazine imide (PTI) embedded with melon domains are fabricated by KCl/LiCl-mediated polycondensation of dicyandiamide, the surface of which is subsequently deposited with ultrafine WO 3 nanoparticles to construct the CCN/WO 3 heterostructure with a S-scheme interface. Systematic characterizations have been conducted to reveal the compositions and structures of the S-scheme CCN/WO 3 hybrid, featuring strengthened optical capture, enhanced CO 2 adsorption and activation, attractive textural properties, as well as spatial separation and directed movement of light-triggered charge carriers. Under mild conditions, the CCN/WO 3 catalyst with optimized composition displays a high photocatalytic activity for reducing CO 2 to CO in a rate of 23.0 µmol/hr (i.e. , 2300 µmol/(hr·g)), which is about 7-fold that of pristine CCN, along with a high CO selectivity of 90.6% against H 2 formation. Moreover, it also manifests high stability and fine reusability for the CO 2 conversion reaction. The CO 2 adsorption and conversion processes on the catalyst are monitored by in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), identifying the crucial intermediates of CO 2 *−, COOH* and CO*, which integrated with the results of performance evaluation proposes the possible CO 2 reduction mechanism. [ABSTRACT FROM AUTHOR]

Acrylamides were shown to significantly improve bonding stability in adhesive restorations, but the reinforcement mechanism has not been fully elucidated. We tested the hypothesis that hydrogen bonding reinforcement of the collagen network (with secondary or tertiary acrylamides), as well as degree of crosslinking of the polymer network (with di- or tri-functional acrylamides), can be two of the factors at play. Two-step total etch adhesives comprising UDMA (60 wt%) and 40 wt% of: TAAEA, TMAAEA (secondary, tertiary tri-acrylamides), BAAP, DEBAAP (secondary, tertiary di-acrylamides) or HEMA (mono-methacrylate - control) were formulated. Simulated composite restorations (n = 5) were tested after cyclic mechanical and biological (S. mutans biofilm) challenges. Gap formation before and after aging was assessed with SEM imaging. Micro-tensile bond strength (μTBS, n = 6) was assessed after seven-day incubation in water or S. mutans -containing culture medium. Collagen reinforcement was assessed with hydroxyproline assay (n = 10) and rheology (n = 3). Data were analyzed with one-way/two-way ANOVA/Tukey's test (alpha=5%). Gap formation increased and bond strength decreased for all monomers after biofilm incubation (p < 0.001). Except for DEBAAP, secondary and tertiary di/tri-acrylamides showed lower occlusal gap width values, but no significant differences overall gap length compared to HEMA. μTBS increased for tri-acrylamides compared with HEMA. Samples treated with multi-acrylamides had lower concentration of hydroxyproline (by-product of collagen degradation) (p < 0.001), except for DEBAAP, which showed values close to HEMA (p > 0.05). Dentin shear modulus increased for all acrylamides after 72 h, especially TMAAEA. In general, multi-acrylamides promote collagen reinforcement, leading to reduced gap formation, and stabilize the bond strength under physiological conditions. [ABSTRACT FROM AUTHOR]

Non-alcoholic steatohepatitis (NASH), now known as metabolic dysfunction-associated steatohepatitis (MASH), involves oxidative stress caused by the overproduction of reactive oxygen species (ROS). Small-molecule antioxidants have not been approved for antioxidant chemotherapy because of severe adverse effects that collapse redox homeostasis, even in healthy tissues. To overcome these disadvantages, we have been developing poly(ethylene glycol)- block -poly(cysteine) (PEG- block -PCys)-based self-assembling polymer nanoparticles (NanoCyses), releasing Cys after in vivo degradation by endogenous enzymes, to obtain antioxidant effects without adverse effects. However, a comprehensive investigation of the effects of polymer design on therapeutic outcomes has not yet been conducted to develop our NanoCys system for antioxidant chemotherapy. In this study, we synthesized different poly(L -cysteine) (PCys) chains whose sulfanyl groups were protected by tert -butyl thiol (S t Bu) and butyryl (Bu) groups to change the reactivity of the side chains, affording NanoCys(SS) and NanoCys(Bu), respectively. To elucidate the importance of the polymer design, these NanoCyses were orally administered to MASH model mice as a model of oxidative stress-related diseases. Consequently, the acyl-protective NanoCys(Bu) significantly suppressed hepatic lipid accumulation and oxidative stress compared to NanoCys(SS). Furthermore, we substantiated that shorter PCys were much better than longer PCys for therapeutic outcomes and the effects related to the liberation properties of Cys from these nanoparticles. Owing to its antioxidant functions, NanoCyses also significantly attenuated hepatic inflammation and fibrosis in the MASH mouse model. [Display omitted] [ABSTRACT FROM AUTHOR]

Colorectal carcinoma (CRC) has become one of the most prevalent malignant tumors and exploring a potential therapeutic strategy with diminished drug-associated adverse effects to combat CRC is urgent. Herein, we designed a pH-responsive polymer to efficiently encapsulate a stimulator of interferon genes (STING) agonist (5,6- dimethylxanthenone-4-acetic acid, termed ASA404) and a common clinically used chemotherapeutic agent (1-hexylcarbamoyl-5-fluorouracil, termed HCFU). Investigations in vitro demonstrated that polymer encapsulation endowed the system with a pH-dependent disassembly behavior (pH t 6.37), which preferentially selected cancerous cells with a favorable dose reduction (dose reduction index (DRI) of HCFU was 4.09). Moreover, the growth of CRC in tumor-bearing mice was effectively suppressed, with tumor suppression rates up to 94.74%, and a combination index (CI) value of less than one (CI = 0.41 for CT26 cell lines), indicating a significant synergistic therapeutic effect. Histological analysis of the tumor micro-vessel density and enzyme-linked immunosorbent assay (ELISA) tests indicated that the system increased TNF-α and IFN-β levels in serum. Therefore, this research introduces a pH-responsive polymer-based theranostic platform with great potential for immune-chemotherapeutic and anti-vascular combination therapy of CRC. [Display omitted] [ABSTRACT FROM AUTHOR]

The biphasic assembly of Gram-positive pili begins with the covalent polymerization of distinct pilins catalyzed by a pilus-specific sortase, followed by the cell wall anchoring of the resulting polymers mediated by the housekeeping sortase. In Actinomyces oris, the pilus-specific sortase SrtC2 not only polymerizes FimA pilins to assemble type 2 fimbriae with CafA at the tip, but it can also act as the anchoring sortase, linking both FimA polymers and SrtC1-catalyzed FimP polymers (type 1 fimbriae) to peptidoglycan when the housekeeping sortase SrtA is inactive. To date, the structure-function determinants governing the unique substrate specificity and dual enzymatic activity of SrtC2 have not been illuminated. Here, we present the crystal structure of SrtC2 solved to 2.10-Å resolution. SrtC2 harbors a canonical sortase fold and a lid typical for class C sortases and additional features specific to SrtC2. Structural, biochemical, and mutational analyses of SrtC2 reveal that the extended lid of SrtC2 modulates its dual activity. Specifically, we demonstrate that the polymerizing activity of SrtC2 is still maintained by alanine-substitution, partial deletion, and replacement of the SrtC2 lid with the SrtC1 lid. Strikingly, pilus incorporation of CafA is significantly reduced by these mutations, leading to compromised polymicrobial interactions mediated by CafA. In a srtA mutant, the partial deletion of the SrtC2 lid reduces surface anchoring of FimP polymers, and the lid-swapping mutation enhances this process, while both mutations diminish surface anchoring of FimA pili. Evidently, the extended lid of SrtC2 enables the enzyme the cell wall-anchoring activity in a substrate-selective fashion. [ABSTRACT FROM AUTHOR]

Zwitterionic polymers possess equal total positive and negative charges in the repeating units, making them electrically neutral overall. This unique property results in superhydrophilicity, which makes the zwitterionic polymers highly effective in resisting protein adsorption, thus endowing the drug carriers with long blood circulation time, inhibiting thrombus formation on biomedical devices in contact with blood, and ensuring the good sensitivity of sensors in biomedical application. Moreover, zwitterionic polymers have tumor-targeting ability and pH-responsiveness, rendering them ideal candidates for antitumor drug delivery. Additionally, the high ionic conductivity of zwitterionic polymers makes them an important raw material for ionic skin. Zwitterionic polymers exhibit remarkable resistance to bacterial adsorption and growth, proving their suitability in a wide range of biomedical applications such as ophthalmic applications, and wound dressings. In this paper, we provide an in-depth analysis of the different structures and characteristics of zwitterionic polymers and highlight their unique qualities and suitability for biomedical applications. Furthermore, we discuss the limitations and challenges that must be overcome to realize the full potential of zwitterionic polymers and present an optimistic perspective for zwitterionic polymers in the biomedical fields. Zwitterionic polymers have a series of excellent properties such as super hydrophilicity, anti-protein adsorption, antibacterial ability and good ionic conductivity. However, biomedical applications of multifunctional zwitterionic polymers are still a major field to be explored. This review focuses on the design and application of zwitterionic polymers-based nanosystems for targeted and responsive delivery of antitumor drugs and cancer diagnostic agents. Moreover, the use of zwitterionic polymers in various biomedical applications such as biomedical devices in contact with blood, biosensors, ionic skin, ophthalmic applications and wound dressings is comprehensively described. We discuss current results and future challenges for a better understanding of multifunctional zwitterionic polymers for biomedical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The development of eco-friendly polymer composites with multifunctional properties aligns with the goals of the circular economy agenda, which aims to minimize waste and promote the sustainable use of resources by closing the loop of product life cycles. Eco-friendly polymer composites play a crucial role in achieving these objectives. The present work focuses on the preparation of fully biobased blends obtained by melt mixing a bio-polyester, poly(butylene succinate- co -adipate) (PBSA), with orange peels up to 20 wt%, to yield active polymer composites. Orange peels, employed here as natural filler, are largely available from food wastes, they are rich in phenolic compounds and possess antioxidant activity as shown by the experimental tests carried out. The thermal stability of the formulated composites is almost unchanged by the filler addition, showing only a slight decrease of the crystallization temperatures and crystalline fraction within the composites. The mechanical properties of the compounds evidence an increase in the elastic modulus together with a decrease in the tensile strength, while the elongation at break remains almost constant. The incorporation of the natural filler enabled the integration of antioxidant and antibacterial properties, which were absent in the original pristine polymer. • PBSA containing up to 20 wt% of orange peels have good antioxidant and antibacterial properties. • Biocomposites formulated with orange peels are found to retain good mechanical properties in terms of elongation at break. • The thermoplastic material produced can be used in the packaging industry or in the organic or integrated farming sector application. [ABSTRACT FROM AUTHOR]

Rapidly dissolving polymer thin films, or oral thin films (OTFs), have recently emerged as an improved oral drug delivery vehicle with its ability to bypass liver first pass metabolism, longer shelf-life, and simpler transport and distribution requirements, compared to traditional tablets and liquid formulations. Loratadine (LOR), an antihistamine commonly used to treat allergic rhinitis, undergoes liver first pass metabolism and is a prime candidate for incorporation within an OTF. However, loratadine is a BCS II drug with low aqueous solubility. Herein, the solubility of loratadine was improved by complexation with methyl β-cyclodextrin (MBCD) by co-evaporation of 2:1, 1:1, and 1:2 LOR:MBCD ratios and incorporation into a pullulan-based OTF at 4 wt% by solvent casting at 50 °C for 30 – 35 min. A therapeutically relevant 10 mg LOR dose could be prepared in a 3 cm by 3 cm OTF. The feasibility of complexation was observed with a B s -type phase solubility diagram, and complexation itself was confirmed via differential scanning calorimetry (DSC) by disappearance of the LOR melting peak, Fourier-transform infrared spectroscopy (FTIR) by shifting of the C=O peak, via 1H NMR spectroscopy by downfield shifting and change in peak multiplicity of the LOR aromatic protons, and via diffusion-ordered spectroscopy by a decrease in the diffusion coefficient of LOR:MBCD complex. LOR:MBCD could be incorporated homogeneously throughout an OTF, and LOR:MBCD OTFs exhibited reasonable mechanical strength and endured 12 ± 3 folds before breaking. LOR:MBCD OTFs disintegrated within 38 ± 10 s. The cumulative in vitro release of LOR:MBCD OTFs peaked at 80 % within 3–4 min of dissolution, and LOR in LOR:MBCD OTFs exhibited permeability across a 0.22 μm nitrocellulose membrane, demonstrating its applicability as a rapid drug delivery vehicle. [Display omitted] [ABSTRACT FROM AUTHOR]

• Consolidation formulations for ceramic artifacts using HPC polymer were done. • Transforming hydrophilic HPC polymer to hydrophobic using nano-silica was done. • Superior properties were achieved using HPC with hydrophobic nano-silica. • Biobased polymers & nanoparticles coats are recommended for artifact conservation. This study focuses on transforming the consolidation formulations based on Hydroxypropyl cellulose (HPC), which is an eco-friendly bio-based cellulosic polymer with inherent hydrophilic characteristics to a hydrophobic one. This will be done via integrating the polymer with nano-silica and hydrophobic nano-silica, to enhance its consolidating properties to be in line with the global trend of replacing conventional materials with eco-friendly alternatives. Three different formulations were prepared, including HPC polymer solely, HPC integrated with nano-silica (NS), and HPC integrated with hydrophobic nano-silica (HNS). Primarily, nano-silica and hydrophobic nano-silica were synthesized and characterized using TEM and XRD. Subsequently, the prepared formulations were applied to artificial ceramic artifacts to evaluate their physical and mechanical properties, encompassing parameters such as water absorption, color change, contact angle, SEM/EDX, and digital microscopy. The results revealed that the incorporation of hydrophobic nano-silica significantly enhanced the mechanical and the physical properties of the cellulosic polymer, besides the extreme change that happened to its hydrophilic properties which was developed to a very good hydrophobic one. The success of these consolidation formulations can pave the way for the utilization of bio-based polymers with their inherent eco-friendly nature in the consolidation and restoration processes of cultural heritage artifacts, which can help in the contribution to the expanding body of knowledge in sustainable materials for conservation purposes. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] A systematic study of the UV light-induced degradation of a series of structurally similar conjugated polymers revealed important relationships between the molecular structure of the used building blocks and photostability of the resulting materials. These findings form a set of important guidelines for future rational design of new absorber materials for efficient and stable organic solar cells. [ABSTRACT FROM AUTHOR]

Severe burn injuries with massive dermal loss are often underestimated despite their significant impact on morbidity and mortality. Resembling the natural extracellular matrix (ECM), hyaluronic acid (HA)-based dressings have been extensively explored as suitable candidates for burn wound treatment. However, native HA hydrogel's limitations, such as low mechanical strength, rapid degradation, and uncontrollable drug delivery, hinder its efficacy, especially for full-thickness burns requiring injectable hydrogels with robust antibacterial and angiogenic capabilities. Herein, we present a novel multifunctional sequential dual-curing hydrogel system, combining hyperbranched poly(DMA-DMAPMA-PEGDA) (DDP) polymer with thiolated hyaluronic acid (HA-SH). The DDP copolymer, featuring multi-vinyls and catechol functionalities, facilitates two curing reactions taking place sequentially with HA-SH under physiological conditions, balancing convenient injection with the mechanical strength essential for effective wound management. Furthermore, the resulting DDP/HA hydrogels demonstrate enhanced therapeutic attributes, including intrinsic angiogenic and antimicrobial effects, setting them as promising dressing options for deep burn wound therapy. [Display omitted] [ABSTRACT FROM AUTHOR]

The properties of nanomedicines will influence how they can deliver drugs to patients reproducibly and effectively. For conventional pharmaceutical products, Chemistry, Manufacturing and Control (CMC) documents require monitoring stability and storage conditions. For nanomedicines, studying these important considerations is hindered by a lack of appropriate methods. In this paper, we show how combining radiolabelling with size exclusion chromatography, using a method called SERP (for Size Exclusion of Radioactive Polymers), can inform on the in vitro degradation of polymer nanoparticles. Using nanoparticles composed of biodegradable poly(lactic acid) (PLA) and poly(lactic- co -glycolic acid) (PLGA), we show that SERP is more sensitive than dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA) to detect degradation. We also demonstrate that the properties of the polymer composition and the nature of the aqueous buffer affect nanoparticle degradation. Importantly, we show that minute changes in stability that cannot be detected by DLS and NTA impact the pharmacokinetic of nanoparticles injected in vivo. We believe that SERP might prove a valuable method to document and understand the pharmaceutical quality of polymer nanoparticles. [Display omitted] [ABSTRACT FROM AUTHOR]

Despite their great versatility and ease of functionalization, most polymer-based nanocarriers intended for use in drug delivery often face serious limitations that can prevent their clinical translation, such as uncontrolled drug release and off-target toxicity, which mainly originate from the burst release phenomenon. In addition, residual solvents from the formulation process can induce toxicity, alter the physico-chemical and biological properties and can strongly impair further pharmaceutical development. To address these issues, we report polymer prodrug nanoparticles, which are prepared without organic solvents via an all-aqueous formulation process, and provide sustained drug release. This was achieved by the " drug-initiated " synthesis of well-defined copolymer prodrugs exhibiting a lower critical solution temperature (LCST) and based on the anticancer drug gemcitabine (Gem). After screening for different structural parameters, prodrugs based on amphiphilic diblock copolymers were formulated into stable nanoparticles by all-aqueous nanoprecipitation, with rather narrow particle size distribution and average diameters in the 50–80 nm range. They exhibited sustained Gem release in human serum and acetate buffer, rapid cellular uptake and significant cytotoxicity on A549 and Mia PaCa-2 cancer cells. We also demonstrated the versatility of this approach by formulating Gem-based polymer prodrug nanoparticles loaded with doxorubicin (Dox) for combination therapy. The dual-drug nanoparticles exhibited sustained release of Gem in human serum and acidic release of Dox under accelerated pathophysiological conditions. Importantly, they also induced a synergistic effect on triple-negative breast cancer line MDA-MB-231, which is a relevant cell line to this combination. [Display omitted] • Well-defined copolymer prodrugs exhibiting a lower critical solution temperature and based on the anticancer drug gemcitabine were synthesized by the "drug-initiated" method. • Their thermosensitivity has enabled them to be formulated into narrowly dispersed nanoparticles by all-aqueous nanoprecipitation, thus avoiding the use of organic solvents. • The copolymer prodrug nanoparticles exhibited sustained gemcitabine release in human serum and acetate buffer, and significant cytotoxicity on A549 and Mia PaCa-2 cancer cells. • They were also loaded with doxorubicin and induced a synergistic effect on a triple-negative breast cancer line MDA-MB-231, which is a relevant cell line to this combination. [ABSTRACT FROM AUTHOR]

Delivery to peripheral lymphatics can be achieved following interstitial administration of nano-sized delivery systems (nanoparticles, liposomes, dendrimers etc) or molecules that hitchhike on endogenous nano-sized carriers (such as albumin). The published work concerning the hitchhiking approach has mostly focussed on the lymphatic uptake of vaccines conjugated directly to albumin binding moieties (ABMs such as lipids, Evans blue dye derivatives or peptides) and their subsequent trafficking into draining lymph nodes. The mechanisms underpinning access and transport of these constructs into lymph fluid, including potential interaction with other endogenous nanocarriers such as lipoproteins, have largely been ignored. Recently, we described a series of brush polyethylene glycol (PEG) polymers containing end terminal short-chain or medium-chain hydrocarbon tails (1C2 or 1C12, respectively), cholesterol moiety (Cho), or medium-chain or long-chain diacylglycerols (2C12 or 2C18, respectively). We evaluated the association of these materials with albumin and lipoprotein in rat plasma, and their intravenous (IV) and subcutaneous (SC) pharmacokinetic profiles. Here we fully detail the association of this suite of polymers with albumin and lipoproteins in rat lymph, which is expected to facilitate lymph transport of the materials from the SC injection site. Additionally, we characterise the thoracic lymph uptake, tissue and lymph node biodistribution of the lipidated brush PEG polymers following SC administration to thoracic lymph cannulated rats. All polymers had moderate lymphatic uptake in rats following SC dosing with the lymph uptake higher for 1C2-PEG, 2C12-PEG and 2C18-PEG (5.8%, 5.9% and 6.7% dose in lymph, respectively) compared with 1C12-PEG and Cho-PEG (both 1.5% dose in lymph). The enhanced lymph uptake of 1C2-PEG, 2C12-PEG and 2C18-PEG appeared related to their association profile with different lipoproteins. The five polymers displayed different biodistribution patterns in major organs and tissues in mice. All polymers reached immune cells deep within the inguinal lymph nodes of mice following SC dosing. The ability to access these immune cells suggests the potential of the polymers as platforms for the delivery of vaccines and immunotherapies. Future studies will focus on evaluating the lymphatic targeting and therapeutic potential of drug or vaccine-loaded polymers in pre-clinical disease models. [Display omitted] • Lipidation of peptides and polymers leads to binding to serum albumin and extension of plasma half-life after injection. • Here we found that lipidated brush PEG polymers are lymphatically transported following subcutaneous (SC) injection in rats. • Lymph uptake was higher on conjugation to diacylglycerols and a short hydrocarbonchain, compared to cholesterol or medium hydrocarbon chain. • Differences in lymph uptake appeared driven by trafficking in association with both lipoproteins and albumin. • All polymers reached immune cells deep within lymph nodes suggesting potential for delivery of vaccines and immunotherapies. [ABSTRACT FROM AUTHOR]

Functionally graded materials (FGMs) such as polymer/ceramic composite have emerged as a prospective candidate for orthopedic implants, as they enable the incorporation of diverse material properties with mechanical biomimetic and biocompatibility of bone scaffolds. This study presents a novel approach for fabricating FGM scaffolds using a simplified additive manufacturing and impregnation-curing process, aiming to develop hydrophilic scaffolds with excellent mechanical properties. The graded composition of the scaffold was confirmed through micro-CT and SEM, with hydroxyapatite (HA) particles embedded on the surface of Polyactive acid (PLA) scaffold. The outermost layer exhibited a uniform distribution of HA with rough morphology, enhancing the hydrophilicity by 20 %. While the internal graded pure PLA core contributed to excellent mechanical strength. By adopting a programmable triply periodic minimal surfaces (TPMS) approach, the relative density of the PLA core has been adjusted to tailor scaffold's mechanical properties. This innovative fabrication method opens avenues for polymer/ceramic composite development in orthopedic implants to enhance long-term stability and biocompatibility. [Display omitted] • Polymer/ceramic functionally graded material scaffold has been fabricated by a novel additive manufacturing. • The ceramics' hydrophilicity and polymer's toughness are integrated into the composite scaffold. • Continuous gradient changes between different materials enhance the bonding properties and avoid delamination cracks. [ABSTRACT FROM AUTHOR]

In this study, the viscous polymer processing (VPP) technique is implemented to optimize the characteristics of bulk (1- x)BaTiO 3 - x Bi(Mg 0·5 Ti 0.5)O 3 (BT- x BMT) lead-free relaxor ferroelectric ceramics, with a focus on enhancing the recoverable energy storage density (W rec), improving breakdown strength resistance (E b), and increasing storage efficiency (η). The influence of polyvinyl alcohol (PVA) inclusion in the VPP process on the resulting dielectric ceramics is thoroughly investigated, covering rheological, dielectric, and ferroelectric properties. The results reveal that a gradual increase in PVA quantity during the VPP process effectively improves the density of ceramic blanks. However, an excess of PVA leads to void formation in the ceramic blanks post-debinding, hindering the achievement of a dense structure in the final ceramics and causing performance degradation. The resulting BT-0.405BMT-40 wt% PVA ceramic showed excellent storage performance, with W rec , η , and E b of 6.55 J/cm3 81.45 %, and 480 kV/cm, respectively. In comparison to bulk BT-0.405BMT ceramics, there is a notable 2.47-fold increase in W rec and a 1.92-fold increase in E b , accompanied by a substantial improvement in η. Moreover, the BT-BMT-40 wt% PVA ceramic exhibits favorable temperature stability (30–150 °C), frequency stability (1–50 Hz), and commendable charge/discharge performance. [ABSTRACT FROM AUTHOR]

• Major fractions of e-waste are composed by plastic polymers. • Unique spectral features are used as proxies for identification of polymer types. • Fast hyperspectral measurements generate 2D maps and identify some polymer types. • Fast Raman measurements identify black plastics and distinguish between ABS/PS. • Multi-sensor sequential measurement (sensor network) can improve polymer recycling. Polymers represent around 25% of total waste from electronic and electric equipment. Any successful recycling process must ensure that polymer-specific functionalities are preserved, to avoid downcycling. This requires a precise characterization of particle compounds moving at high speeds on conveyor belts in processing plants. We present an investigation using imaging and point measurement spectral sensors on 23 polymers including ABS, PS, PC, PE-types, PP, PVC, PET-types, PMMA, and PTFE to assess their potential to perform under the operational conditions found in recycling facilities. The techniques applied include hyperspectral imaging sensors (HSI) to map reflectance in the visible to near infrared (VNIR), short-wave (SWIR) and mid-wave infrared (MWIR) as well as point Raman, FTIR and spectroradiometer instruments. We show that none of the sensors alone can identify all the compounds while meeting the industry operational requirements. HSI sensors successfully acquired simultaneous spatial and spectral information for certain polymer types. HSI, particularly the range between (1600–1900) nm, is suitable for specific identification of transparent and light-coloured (non-black) PC, PE-types, PP, PVC and PET-types plastics; HSI in the MWIR is able to resolve specific spectral features for certain PE-types, including black HDPE, and light-coloured ABS. Fast-acquisition Raman spectroscopy (down to 500 ms) enabled the identification of all polymers regardless their composition and presence of black pigments, however, it exhibited limited capacities in mapping applications. We therefore suggest a combination of both imaging and point measurements in a sequential design for enhanced robustness on industrial polymer identification. [ABSTRACT FROM AUTHOR]

Amorphous silica precipitation from aqueous solutions at low temperatures (<100 °C) involves the initial nucleation and growth of silica polymers followed by aggregation, cementation and recrystallization to form opaline silica. In this study, silica polymerization was studied at temperature 23–80 °C, pH 2.48–9.65, and ionic strength 0.01–0.53 mol kg−1. Measured changes in the concentration of monomeric silica (SiO 2(mono)) were fit assuming the polymerization reaction is fourth-order with respect to the difference between the concentration of silicic acid ( Si (OH) 4(aq)) and its concentration at equilibrium ( Si(OH) 4(aq) eq) with respect to amorphous silica: r = - k 4 A s m S i (O H) 4 (a q) - m S i (O H) 4 (a q) e q 4 where r is the overall rate of the reaction, A s is the specific surface area of the formed polymers, calculated assuming particle-size-dependent solubility and a spherical polymer geometry, and k 4 is the rate constant. The rate constant at zero ionic strength is given by: k 0 = A e x p - E a / R T a OH - n where A is a pre-exponential constant (0.3822 mmol−3 cm−2 s−1), E a is the activation energy (29.87 kJ mol−1), and n is equal to −0.80. The overall rate constant as a function of ionic strength (I) is given by: k 4 = k 0 I m where m is equal to 0.65. The rate constant increases by approximately six orders of magnitude from pH of 2 to 10 and one order of magnitude between temperature ∼20 and 80 °C. However, hydrolysis of silicic acid (Si (O H) 4 (aq) ) at pH above ∼8 decreases the relative abundance of Si (O H) 4 (aq) while increasing the solubility of amorphous silica, thereby decreasing the rate of silica polymerization. The inferred reaction order is consistent with a reaction mechanism rate-limited by the formation of the cyclic tetramer across a wide range of pH. The time-dependence of the specific surface area during polymerization reflects the formation of critical nuclei towards the beginning of the polymerization process and Ostwald ripening of larger polymers towards the end of the polymerization process. The developed rate equation can predict rates of silica polymerization across a wide range of aqueous solution compositions. [ABSTRACT FROM AUTHOR]

Polyphenol contained polymers were developed to form a nanocoating on the surface of tumor cells to block their key metabolite transport processes for tumor treatment, while suppressing metastasis and invasion, providing a promising anticancer candidate with a mechanism by impeding the mass transport of tumor cells. [Display omitted] The metabolite transport inhibition of tumor cells holds promise to achieve anti-tumor efficacy. Herein, we presented an innovative strategy to hinder the delivery of metabolites through the in-situ besieging tumor cells with polyphenolic polymers that strongly adhere to the cytomembrane of tumor cells. Simultaneously, these polymers underwent self-crosslinking under the induction of tumor oxidative stress microenvironment to form an adhesive coating on the surface of the tumor cells. This polyphenol coating effectively obstructed glucose uptake, reducing metabolic products such as lactic acid, glutathione, and adenosine triphosphate, while also causing reactive oxygen species to accumulate in the tumor cells. The investigation of various tumor models, including 2D cells, 3D multicellular tumor spheroids, and xenograft tumors, demonstrated that the polyphenolic polymers effectively inhibited the growth of tumor cells by blocking key metabolite transport processes. Moreover, this highly adhesive coating could bind tumor cells to suppress their metastasis and invasion. This work identified polyphenolic polymers as a promising anticancer candidate with a mechanism by impeding the mass transport of tumor cells. [ABSTRACT FROM AUTHOR]

Two new magnetic/ceramic/carbon and magnetic/ceramic/polymer/carbon nanocomposites were created by decorating the surface of MWCNT with magnetic/ceramic (Fe 2 O 3 /Fe 3 O 4 /SiO 2 NPs) and magnetic/ceramic/polymer (Fe 2 O 3 /Fe 3 O 4 /SiO 2 /PANI). First, in order to have a narrow size distribution and high saturation magnetization, Fe 2 O 3 /Fe 3 O 4 NPs were produced successively under ideal conditions. Subsequently, Fe 2 O 3 /Fe 3 O 4 NPs were produced by coating them with a thin layer of SiO 2. Fe 2 O 3 /Fe 3 O 4 /SiO 2 /MWCNT nanocomposite was created by applying Fe 2 O 3 /Fe 3 O 4 /SiO 2 /NPs at a specified weight ratio (1/2) to the MWCNT surface. Subsequently, Fe 2 O 3 /Fe 3 O 4 /SiO 2 NPs were utilized as an initiator to polymerize the aniline; as a result, Fe 2 O 3 /Fe 3 O 4 /SiO 2 /PANI NPs were created and the polyaniline grew at their surface. Ultimately, Fe 2 O 3 /Fe 3 O 4 /SiO 2 /PANI NPs were added to MWCNT at a weight ratio of 1/2, resulting in the synthesis of a Fe 2 O 3 /Fe 3 O 4 /SiO 2 /PANI/MWCNT nanocomposite. XRD, SEM, and TEM pictures verified the effective synthesis of Fe 2 O 3 /Fe 3 O 4 /SiO 2 /MWCNT and Fe 2 O 3 /Fe 3 O 4 /SiO 2 /PANI/MWCNT nanocomposites. By evaluating their EM characteristics, the microwave absorption properties of these composites were characterized. The findings shown that for the Fe 2 O 3 /Fe 3 O 4 /SiO 2 /MWCNT nanocomposite with an effective bandwidth of 5.7 GHz, the minimum reflection loss reached −18.5 dB. For the Fe 2 O 3 /Fe 3 O 4 /SiO 2 /PANI/MWCNT nanocomposite, there was a considerable improvement in both minimum reflection loss and bandwidth in comparison with similar composites. The Fe 2 O 3 /Fe 3 O 4 /SiO 2 /PANI/MWCNT demonstrated a minimum reflection loss of −87dB over whole frequency range (8–18 GHz) with an effective bandwidth. [ABSTRACT FROM AUTHOR]

Tröger's-based polymeric membranes have received tremendous attention for their inherent high free volume and excellent gas permeability. However, its selectivity was still unable to meet their industrial demand. In effort to achieve an optimization comprehensive performance, a set of homogeneous polymer chains was synthesized to fine-tune the free volume. These membranes were designed by copolymerization diamine moiety of 3, 3′-dimethylbiphenyl-4, 4′-diamine and 2, 2-bis [4-(4-aminophenoxy)phenyl] hexafluoropropane. Significant characterizations of their physical properties and chemical structures were carried out by FTIR, TGA, XRD, and mechanical strength. The effects of variation diamine content ratio were studied. An available simulation was carried out to elucidate the influence of introduced diamine. The permselectivity of membranes was evaluated by H 2 , CO 2 , O 2 , N 2 , and CH 4. The objective performances of feed gas pressure, test temperature, and aging stability on membranes were further studied. The exciting results demonstrated that our membranes exhibit improved gas performance. Notably, for H 2 separation, the H 2 /N 2 and H 2 /CH 4 selectivity was significantly enhanced by 125.7% (from 27.20 to 61.40) and 126.9% (from 30.41 to 69.02) with the addition of 30 mol% fluorinated diamine moiety while without much-compromising gas permeability was observed. These findings enlighten a facile and effective strategy in Tröger's-based polymer design towards high-purity gas separation. • Composite Tröger's-based polymeric membrane was prepared for gas separation. • Fluorinated aryl ether moiety diamine was used to tuning the free volume of membranes. • The H 2 /N 2 and H 2 /CH 4 selectivity was enhanced by 125.7 % and 126.9 % with the addition of 30 mol% diamine. • The attracted H 2 /CH 4 performance was very approached to the 2008 Robeson's upper bound. [ABSTRACT FROM AUTHOR]