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In an effort for further improvement of LSCF hollow fiber membrane properties in oxygen purification application, this work studied the use of polyethylene glycol (PEG) with different molecular weight of 2000, 3400 and 6000 Da as a pore former. A well-prepared hollow fiber membrane was successfully fabricated via extrusion followed by a sintering method. The results showed that the addition of PEG increased the viscosity of the dope suspension and formed a constant asymmetric pore configuration of the membrane after sintering at 1250 °C. The increasing molecular weight of PEG also leads to a decrease in the mechanical strength of the membranes, indicating that finger-like pores were sacrificed by forming irregular pores. The gas tightness was also examined under room temperature which showed that membrane with PEG 3400 achieved the best tightness with the nitrogen permeability of 3.55 × 10−5 mol·m−2·s−1·Pa−1. The oxygen permeation of the membranes was also influenced by the addition of PEG, where the highest oxygen permeation flux of 6.07 × 10−8 mol·cm−2·s−1 was obtained using a hollow fiber membrane with PEG 3400 due to the existence of the lowest dense layer thickness.

A CexCoyCuz oxide composite catalyst was prepared by using polyethylene glycol, citrate sol-gel method combined with PMMA template for the oxidation of o-xylene. The catalyst was characterized by the X-ray diffraction (XRD), H2-temperature programmed reduction (H2-TPR), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR), etc. The catalytic activity for o-xylene was investigated. The catalytic degradation pathway and mechanism of o-xylene were inferred. The results show that CeO2 is mainly present on the surface of all catalysts. The surface area of Ce2Co1Cu1 is up to 77.2 m2/g, and the average pore size is 10.62 nm. It exhibits redox and sufficient Ce4+ and Ce3+, and reactive oxygen species, and has maximum O–H and C=O in the five catalyst samples. The catalytic activity of Ce2Co1Cu1 is the best at low temperature, giving the T50 and T90 of 235 °C and 258 °C at a space velocity of 32000 h–1, respectively. The o-xylene is oxidized to o-methyl benzaldehyde, and then further oxidized to o-methylbenzoic acid, and finally CO2 and H2O are formed.

Recently, 3D bioprinting has been explored as a promising technology for biomedical applications with the potential to create complex structures with precise features. Cell encapsulated hydrogels composed of materials such as gelatin, collagen, hyaluronic acid, alginate and polyethylene glycol have been widely used as bioinks for 3D bioprinting. However, since most hydrogel-based bioinks may not allow rapid stabilization immediately after 3D bioprinting, achieving high resolution and fidelity to the intended architecture is a common challenge in 3D bioprinting of hydrogels. In this study, we have utilized shear-thinning and self-healing ionically crosslinked oxidized and methacrylated alginates (OMAs) as a bioink, which can be rapidly gelled by its self-healing property after bioprinting and further stabilized via secondary crosslinking. It was successfully demonstrated that stem cell-laden calcium-crosslinked OMA hydrogels can be bioprinted into complicated 3D tissue structures with both high resolution and fidelity. Additional photocrosslinking enables long-term culture of 3D bioprinted constructs for formation of functional tissue by differentiation of encapsulated human mesenchymal stem cells.

An innovative application of the solvent evaporation technique was suggested. Solvent evaporation technique is a technique for drug encapsulation and nanosphere preparation. Th widely used technique is also facing the problem of low actual drug entrapment percent, which is not economic from the industrial view. The goal of this work is trying to use the advantage of this technique concerning the product sphericity and the ability to control particle size, to prepare a drug as pure crystals spheres. Ibuprofen is selected as a model drug. The spheres are formed by using Polyvinyl pyrrolidone (PVP) or Polyethylene glycol (PEG) as an antiaggregating agent but not formed on using tween or span. Particle size and actual drug content depend on the concentrations the antiaggregating agent used. Surfaces of the drug crystal spheres are porous with empty sphere internal structure on using PVP but spongy and rough on using PEG. The drug has its identity chemical form in the drug crystal spheres. IR scan of spheres prepared on using PEG showed a characteristic ether peak. DSC showed melting endothermic peak of PEG, but X-ray showed minor change in the drug crystal patterns. Drug release profiles from crystal spheres prepared with the same antiaggregating agent are close to each other. The drug release profiles from drug crystal spheres prepared by using PEG are more controlled than that prepared by using PVP. The drug release mechanism is diffusion. It was concluded that, the same technique could be suggested for preparation of other biomedical material in pure crystals spheres with controlled particle size. These properties may encourage to prepare very small particles with spherical shape for inhalation or injection as an innovative particle technology application for the widely used technique.

In the present study, composites of Polyaniline and some fruit peels were synthesized in various conditions and used for lead removal from aqueous solutions. Adsorption tests were conducted in batch mode using the most efficient adsorbent, and the effects of medium pH, initial lead concentration, contact time, adsorbent dosage, and adsorption isotherms were investigated. The results showed that all composites were more efficient in lead removal compared to the fruit peels alone. The highest removal percentage was related to the composite of banana peel and Polyaniline that synthesized in the aqueous solution in the presence of 2 g·L−1 Poly ethylene glycol. This composite showed 95.96% lead adsorption at pH=6, the contact time of 90 min, the initial lead concentration of 25 mg·L−1, and an adsorbent concentration of 8 g·L−1. Adsorption isotherm study showed that adsorption of lead by synthesized composite could be fitted by both Langmuir and Freundlich models, but the Langmuir model was more fitted than Freundlich. Besides, some characteristics of the composites, such as chemical composition (XRD analysis), structure, and morphology (SEM analysis) and functional groups (FTIR analysis), were studied.

Carbon dots (CDs) have attracted more interest in tumor theranostics, but they suffer from the rapid renal clearance due to small size and high hydrophilicity. To solve such problems, hydrophobic pH-triggered carbon dot-drug conjugate (CDs-Hy-DOX) with high doxorubicin (DOX) content of 48.23% were designed by covalent conjugation of DOX onto the CDs via acid-labile linkage with hydrazine (Hy) as bridge. Then the fluorescent traceable hybrid prodrug nanoparticles were fabricated via co-self-assembly with the CDs-Hy-DOX as pH-sensitive prodrug and a pH/reduction dual-triggered degradable hyperbranched polymer PEG-PO-Cy as polyethylene glycol (PEG)-based surfactant, as well as gatekeeper for pH/reduction dual-triggered DOX release. The hybrid prodrug nanoparticles with hydrodynamic diameter of 220 nm and DOX content of 22.99% were obtained with the optimized co-self-assembling condition. They could release 68.98% of DOX in the simulated tumor microenvironment within 3 days in a sustained release mode, with a premature drug leakage of 7.58%. After the acid-triggered DOX release from the CDs-Hy-DOX, which was accelerated by the pH/reduction dual-triggered degradation of the hyperbranched polymer, the strong fluorescence of CDs-Hy was recovered, demonstrating the promising potential in future tumor nanotheranostics.

Aqueous zinc metal batteries (AZMBs) directly utilizing Zn metal anode have been regarded as a promising candidate for the next generation commercial batteries featuring high safety, high theoretical capacity, and appealing chemical stability. However, narrow electrochemical stability windows of aqueous electrolytes, uncontrolled dendrite and limited reversibility still plague its practical applications. Herein, we present a strategy via engineering dilute aqueous Zn(OTf)2 solutions electrolytes with a polyethylene glycol (PEG) network, which substantially decreases the activity of water molecules, and simultaneously enables smooth Zn deposition with a (002) textured and a favorable ZnF2-rich SEI. As a result, symmetric cells with PEG-H2O system show record high cyclic performance (9000 h and 8000 h at current densities of 1 and 2 mA cm−2, respectively), superior interfacial stability and dendrite-free morphology after repeated plating/stripping. Additionally, Zn||70%PEG||V2O5 full batteries also deliver a remarkable energy density of 324.3 W h Kg−1 at a power density of 466.9 W Kg−1 and maintain 84.3% of the capacity over 500 cycles at a high current density of 15 A g−1. All these comprehensive results demonstrate that this electrolyte structural engineering can provide a promising direction for designing high reversibility, long-cycling life aqueous Zn metal batteries.

Hypothesis Complex fluids comprising polymers and surfactants exhibit interesting properties which depend on the overall composition and solvent quality. The ultimate determinants of the macroscopic properties are the nano-scale association domains. Hence it is important to ascertain the structure and composition of the domains, and how they respond to the overall composition. Experiments The structure and composition of mixed micelles formed in aqueous solution between poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) block copolymers (Pluronics or Poloxamers) and the ionic surfactant sodium dodecylsulfate (SDS) are determined from an analysis of small-angle neutron scattering (SANS) intensity data obtained at different contrasts. Different polymers and concentrations have been probed. Findings The SDS + Pluronic mixed micelles include polymer and some water in the micelle core that is formed primarily by alkyl chains. This is different than what was previously reported, but is consistent with a variety of experimental observations. This is the first report on the structure of SDS + Pluronic P123 (EO19PO69EO19) assemblies. The effects on the mixed micelle structure and composition of the surfactant concentration and the polymer hydrophobicity are discussed here in the context of interactions between the different components.

The present study aims at assessing the ballistic impact behaviour of jute reinforced polyethylene glycol (PEG) and nano silica based shear thickening fluid (STF). Preparation of STF is achieved by dispersing the nano silica particles at different weight percentage loadings of 10%, 20%, 30% and 40% in PEG and the effect of various weight percentages loading of nano silica particles on ballistic performance of the proposed composites is studied experimentally. Rheological studies of the prepared STF’s showed that at all nanosilica loading shear thickening occurred and also the shear thickening was highest at higher loading of nano silica at lower rate of shear. The study reveals that the ballistic performance of the jute fabric is enhanced with impregnation of STF. The ballistic results indicate that energy absorption of the proposed composites is enhanced with increased loading of nano silica particles and at the same time, the effect of STF was reduced. Specific energy absorption (SEA) of the neat fabric and the proposed composites was made use of for the purpose of comparing the energy absorption capabilities. It is found that the SEA of proposed composites with 10% nano silica loading is lesser than the neat fabric both in case of 3 layers and 6 layers. It was also found that proposed composite with 40% nano silica loading exhibits highest SEA compared to neat fabric and its counterparts with its SEA being 3.21 and 3.76 times highest compared to three and six layers of neat fabrics respectively.

Tissue engineered cardiac patches have great potential as a therapeutic treatment for myocardial infarction (MI). However, for successful integration with the native tissue and proper function of the cells comprising the patch, it is crucial for these patches to mimic the ordered structure of the native extracellular matrix and the electroconductivity of the human heart. In this study, a new composite construct that can provide both conductive and topographical cues for human induced pluripotent stem cell derived cardiomyocytes (iCMs) is developed for cardiac tissue engineering applications. The constructs are fabricated by 3D printing conductive titanium carbide (Ti3C2Tx) MXene in pre-designed patterns on polyethylene glycol (PEG) hydrogels, using aerosol jet printing, at a cell-level resolution and then seeded with iCMs and cultured for one week with no signs of cytotoxicity. The results presented in this work illustrate the vital role of 3D-printed Ti3C2Tx MXene on aligning iCMs with a significant increase in MYH7, SERCA2, and TNNT2 expressions, and with an improved synchronous beating as well as conduction velocity. This study demonstrates that 3D printed Ti3C2Tx MXene can potentially be used to create physiologically relevant cardiac patches for the treatment of MI.

The mass attenuation coefficients (μm) of polyethylene glycol (PEG) of different molecular weights (1000–200,000) were measured using single-beam photon transmission. The X-ray fluorescent (XRF) photons from Zinc (Zn), Zirconium (Zr), Molybdenum (Mo), Silver (Ag) and Cadmium (Cd) targets were used to determine the attenuation of gamma radiation of energy range between 8.67 and 23.19 keV in PEG samples. The results were compared to theoretical values using XCOM and Monte Carlo simulation using Geant4 toolkit which was developed to validate the experiment at those certain energies. The mass attenuation coefficients were then used to compute the effective atomic numbers, electron density and half value layers for the studied samples. The outcomes showed good agreement between experimental and simulated results with those calculated theoretically by XCOM within 5% deviation. The PEG 1000 sample showed slightly higher μm value compared with the other samples. The dependence of the photon energy and PEG composition on the values of μm and HVL were investigated and discussed. In addition, the values of Zeff and Neff for all PEG samples behaved similarly in the given photon energy range, and they decreased as the photon energy increased.

Pseudomonas stutzeri MTCC 101 was explored as new bacterial strain for secreting anticancer L-methioninase. The partitioning study of this enzyme was further performed using Aqueous two-phase system (ATPS) and Triple phase system. Polyethylene glycol (PEG 4000) and magnesium sulfate (MgSO4) was selected as suitable ATPS system for its partitioning with higher partition coefficient (1.92) and 80% yield. Triple phase partition system (TPP) using n-butanol: ammonium sulphate showed its lower degree of yield (51.6%). ATPS phase components of PEG 4000 and MgSO4 was supplemented with its production media for highly recovery of L-methioninase. The culture condition (pH, temperature, inoculum volume, incubation period and agitation speed) during extractive fermentative production of L-methioninase was optimized using Response surface methodology (RSM). This model showed good adequacy with high value of coefficient of determination (R2) as 99.62%. The experiment was validated under statistically optimized culture condition with higher value of yield as 94.909%. This improved rate of yield of L-methioninase during extractive fermentative condition at optimized cultute conditions were significant finding for this research work. This extractive fermentative approach could be used as low cost-effective downstream processing techniques for its large-scale production in industry.

Utilizing eggshells to synthesize a value added product like nanocrystalline hydroxyapatite (HA) has received a lot of attention from researchers since they are composed of CaCO3 with biologically essential trace elements such as Mg, Si, etc. Different biomedical applications need HA with appropriate nanoscale characteristics like crystallinity, particle size, morphology, surface area, mesoporous nature, etc. The same can be achieved by tuning the reaction parameters, choosing a suitable mode of preparation and utilizing organic modifiers. Here, we report the rapid synthesis of eggshell derived HA in the presence different organic modifiers using a custom built microwave reactor employing the previously optimized parameters. The synthesis process is relatively rapid and gets completed in 5 min. The absence of an organic modifier yielded inhomogeneous size nanorods in the range of 40 – 600 nm. Ethylenediaminetetraacetic acid (EDTA) assisted synthesis resulted in a flower like 1.67 ± 0.12 μm sized HA. Whereas polyethylene glycol 6000 (PEG) and cetyltrimethylammonium bromide (CTAB) assisted synthesis produced aggregated nanorods of length 31 ± 8 and 68 ± 20 nm, respectively. While the synthesis with trisodium citrate dihydrate (TSC) resulted in needles of HA with typical length of 32 ± 8 nm. Presence of Na, Mg and Si trace elements are confirmed from the composition analysis. All the samples are found to be mesoporous in nature. The in vitro cell culture experiment carried out using fibroblast NIH 3T3 cell line clearly revealed equal or higher cell viability for the samples synthesized in presence of organic modifiers as compared to sample produced without organic modifier. Thus, from the present study we find that the synthesis of eggshell derived HA using different organic modifiers via a custom built microwave reactor can be a potential approach for the rapid preparation of precursor materials with suitable nanoscale characteristics for developing bone fillers, drug/protein delivery carriers, tissue engineering scaffolds, etc.

To reveal the influence of organic polymer supports on the properties of shape stabilized phase change materials (ssPCMs), a linear polyurea (LP) and crosslinked polyurea (CP) were synthesized for stabilizing polyethylene glycol (PEG) for thermal energy storage. Though the surface area of LP are about 25 times of that of CP, the shape stability of CP for melt PEG is better than that of LP. Due to the crosslinked network, CP has much stronger interactions with PEG, which could promote the adsorption capacity of PEG. The highest PEG loading capability of LP and CP without liquid leakage above melting point is 70 wt% and 80 wt% respectively, and the corresponding melting enthalpy is 95.42 J/g and 107.60 J/g respectively. However, the heat storage efficiency of PEG/LP ssPCMs is higher than that of PEG/CP ssPCMs with the same PEG content, which caused by the weak restrictions of free movement of PEG chains from LP. Both types of ssPCMs exhibit good reusability from thermal cycle test and good thermal stability from thermal analysis, and the thermal conductivity of ssPCMs can effectively enhance after adding some carbon materials. The study supplied an inspiration to select proper polymer matrix for ssPCMs.

Latent fingerprint recognition technique has received increasing attention because it helps to precisely identify human information for many applications. In this study, bifunctional core-shell magnetic fluorescent microspheres have been synthesized via a facile interface Pechini-type sol-gel method using citric acid and polyethylene glycol as chelating agent and cross-linking agent, respectively. The obtained Fe3O4@YVO4:Eu3+ microspheres possess a typical core-shell structure, large magnetization, and strong fluorescence emission. The surface morphology and roughness of the microspheres can be flexibly tuned by controlling the multistep interface deposition process and subsequent calcination temperatures. Due to their well-integrated bifunctionalities, these magnetic fluorescent microspheres show outstanding performance in the visualization of latent fingerprints on various substrates with high definition and excellent anti-interference, and therefore they have great potential for application in identity recognition.

Anticipating an increasing demand for hybrid double network (DN) hydrogels in biomedicine and biotechnology, this study evaluated the effects of each network on the mechanical and biological properties. Polyethylene glycol (PEG) (meth)acrylate hydrogels with varied monomer molecular weights and architectures (linear vs. 4-arm) were produced with and without an added ionically bonded alginate network and their mechanical properties were characterized using compression testing. The results showed that while some mechanical properties of PEG single network (SN) hydrogels decreased or changed negligibly with increasing molecular weight, the compressive modulus, strength, strain to failure, and toughness of DN hydrogels all significantly increased with increased PEG monomer molecular weight. At a fixed molecular weight (10 kDa), 4-arm PEG SN hydrogels exhibited better overall mechanical performance; however, this benefit was diminished for the corresponding DN hydrogels with comparable strength and toughness and lower strain to failure for the 4-arm case. Regardless of the PEG monomer structure, the alginate network made a relatively larger contribution to the overall DN mechanical properties when the covalent PEG network was looser with a larger mesh size (e.g., for larger monomer molecular weight and/or linear architecture) which presumably enabled more ionic crosslinking. Considering the biological performance, adipose derived stem cell cultures demonstrated monotonically increasing cell area and Yes-associated protein related mechanosensing with increasing amounts of alginate from 0 to 2 wt.%, demonstrating the possibility for using DN hydrogels in guiding musculoskeletal differentiation. These findings will be useful to design suitable hydrogels with controllable mechanical and biological properties for mechanically demanding applications. STATEMENT OF SIGNIFICANCE: Hydrogels are widely used in commercial applications, and recently developed hybrid double network hydrogels have enhanced strength and toughness that will enable further expansion into more mechanically demanding applications (e.g., medical implants, etc.). The significance of this work is that it uncovers some key principles regarding monomer molecular weight, architecture, and concentration for developing strong and tough hybrid double network hydrogels that would not be predicted from their single network counterparts or a linear combination of the two networks. Additionally, novel insight is given into the biological performance of hybrid double network hydrogels in the presence of adipose derived stem cell cultures which suggests new scope for using double network hydrogels in guiding musculoskeletal differentiation.

Despite tremendous advances in gas therapy, there are major concerns about the inevitable concentration of toxicity and the ability to perform real-time tracking of drug delivery. Second near-infrared (NIR-II) window absorbing nanoplatforms hold great promise for precision medicine because of their excellent tissue penetration of light and non-invasive nature. In this study, we engineered an NIR-II laser-activated theranostic agent (named CP-bF@PEG) that was composed of amphiphilic polymers (Pluronic F127, with polyethylene glycol, PEG, moieties) coated with an NIR-II-absorbing conjugated polymer (PTTBBT, CP) and nitric oxide (NO) donor (benzofuroxan, bF), which served as an NIR-II photothermal inducer and NO nanogenerator. Under deep tissue penetration of NIR-II laser irradiation, CP-bF@PEG was found to possess fluorescence imaging ability to accurately identify tumor and excellent photothermal effect. Moreover, CP-bF@PEG could generate NO via glutathione activation in the tumor microenvironment in a controllable manner. This NIR-II-absorbing polymer for high-contrast NIR-II fluorescence imaging-guided precision photothermal therapy achieved synergistic effects with NO therapy, as evidenced by pronounced tumor therapeutic efficacy and few side effects. This nanotheranostic agent is a highly promising candidate for high-contrast NIR-II imaging-guided precision photothermal therapy combined with gas therapy against cancer.

Non-equilibrium molecular dynamic (NEMD) simulation was carried out to calculate the shear viscosities based on the periodic perturbation method. Six binary systems composed of polyethylene glycol monolaurate (PEGML) in aliphatic alcohols were studied, namely PEGML with methanol, ethanol, 2-propanol, 2-butanol, tert-butanol, and 1-pentanol, respectively. The simulated systems were subjected to an external shear-stress acceleration field which induces a velocity gradient of the liquid, and the shear viscosity was further determined from the resulting velocity. Different values of shear-stress acceleration in the range of (0.005 to 0.08) nm ps2 were used to perform an independent simulation. The viscosity was further calculated for each of shear-stress acceleration rate and then extrapolated to obtain the zero-shear rate viscosity. It is found that the shear viscosity follows the order of PEGML + tert-butanol > PEGML + 1-pentanol > PEGML + 2-butanol > PEGML + 2-propanol > PEGML + ethanol > PEGML + methanol, respectively.

Microwave synthesis method was adopted to prepare CdO nanoparticles using polyethylene glycol (PEG), NH3 and NaOH as a co-reagent. A systematic investigation by XRD, SEM, TEM and EDS has been undertaken to evaluate the role of co-reagents on the microstructural and morphological study of the metal oxide nanostructure obtained. The pH of the solution, determined by the co-reagent used, was the main parameter addressing the morphology of CdO nanostructures obtained. By using NH3 the growth of individual CdO particle is favored at the low pH of 9, likely due to low Cd supersaturation rate at this pH. On the other hand, the presence of NaOH as co-reagent increases pH to 11, enhancing Cd supersaturation and leading mainly to formation of nanowire aggregates. The optical and photoluminescence characteristics of the different CdO nanostructures synthesized have been also evaluated.

Adding phase change materials in building walls or roofs can help control the inner temperature of buildings. A kind of composite phase change material, sulphoaluminate cement-based polyethylene glycol (SPEG), can be prepared by blending polyethylene glycol (PEG)-water solution with sulphoaluminate cement. This study aims at improving the heat storage capacity of SPEG using five water-cement ratios (i.e., 0.2, 0.3, 0.4, 0.5 and 0.6). The microstructure, chemical composition, phase change characteristic, thermal and mechanical properties of the SPEGs were investigated, respectively. The results showed that with the increase of water-cement ratio, more hydration products were generated, and the precipitated PEG adhered to the surfaces of the hydration products. Although PEG did not change the hydration product types, it slowed the hydration process. When the water-cement ratio was 0.5, the heat enthalpy of SPEGs could reach up to 40.31 J/g. All the prepared SPEGs could keep their thermal stability under the temperature of 300 °C. After 200 thermal cycles the phase change enthalpy and temperature of SPEGs changed in a very small range. The thermal conductivity, compressive and flexural strength all increased with the increase of water-cement ratio, although the addition of PEG negatively affected the above indicators. The findings in this study are expected to help prepare cement-based phase change materials with high heat storage capacity.

To overcome the leakage of phase change materials (PCMs) above melting temperature, PCMs are commonly encapsuled by chemically crosslinked networks, which bring the issues of reparability, reprocess-ability and recyclability making for the environment pollution and resource waste. Herein, a reversible aromatic disulfide is adopted to form dynamic epoxy networks which not only encapsulate polyethylene glycol (PEG) as the shape-stabilized PCMs (SSPCMs) but also address the issues about the un-recyclability of traditional SSPCMs. The PEG was well encapsulated and uniformly dispersed in disulfide-based epoxy due to the elaborate molecular design. The obtained SSPCMs (named EXAP2) shows typical solid–solid phase transitions characteristic and thermal reliability with high latent heat value of 82.7 J/g. Besides, the EXAP2 exhibit dynamic performance and can be reprocessed by hot press via the disulfide bonds exchange reaction above topology freezing temperature (Tv). And the reprocessed EXAP2 exhibits close phase change properties with the original sample, implying the reprocessing does not affect the crystalline structure and encapsuling capability of disulfide crosslinked networks. This strategy prove a significant way for fabricating the novel SSPCM with recyclability, reprocessability and reliability.

Curtains with light-to-heat conversion capacity can warm up a room under solar radiation and improve the thermal energy efficiency of buildings, thereby reducing energy consumption during winter. Herein, a photothermal silk fibroin aerogel is synthesized by freeze-drying and curing method, using silk fibroin (SF) as template and scaffold, copper sulfide nanoparticles (CuS NPs) as photothermal conversion material, polyethylene glycol (PEG) as plasticizer, and polydimethylsiloxane (PDMS) as the package agent. The results reveal that SF as the template may guide the growth of CuS NPs, and the introduction of PEG improves the flexibility of the prepared CuS@SF aerogel. The composite CuS@SF-PEG/PDMS aerogel not only preserves the initial characteristics of SF aerogel but also integrates hydrophobic, rapid antibacterial ability, high-performance photothermal conversion efficiency, and stable switching effect. The lightweight, self-heating SF-based aerogel can be applied to the preparation of home textiles such as smart curtains. Additionally, it can be used as absorbent for cleaning up viscous oil from water, which could expand the applications of SF-based biomaterials toward meeting the requirements of sustainable developments.

Liquid-solid phase change materials (PCMs) show reversible storage and release of latent heat, which has attracted extensive interests in applications for thermal energy storage. However, stubborn leakage issue may cause corrosion and extra thermal resistance. The non-wettability of melted paraffin on the oleophobic surface of diatomite has been reported by authors earlier, and the result showed that the encapsulation ratio (84.5%) of diatomite@paraffin shape-stabilized PCM greatly increased. Here, in order to prove this method equally applicable to other PCMs and porous natural clay minerals, diatomite and sepiolite were oleophobically modified to encapsulate melted stearic acid and paraffin, to form shape-stabilized PCMs. The results showed that the encapsulation ratios of 67.8% and 56.6% for diatomite@stearic acid and sepiolite@paraffin were higher than that reported in the references (28.9% and 36.8%). In addition, the encapsulation ratios of diatomite-based shape-stabilized PCMs can be also increased using different PCMs, such as n-octadecane and polyethylene glycol via the same approach. Therefore, this is a universal method for improving encapsulation ratios of shape-stabilized PCMs.

Incorporation of silver nanowires in conductive adhesives leads to the reduction of resistivity due to the increased surface area and reduction of contact resistance. However, due to high surface energy, aggregation in the adhesive polymeric matrix leads to performance decline. In this research, in order to solve the aggregation issue and increase the contact surface area, silver nanowires functionalized with carboxylate groups and 21.6 μm and 130.5 nm lengths and diameters were synthesized via polyol technique with a −49.7 mV zeta potential at pH = 7 in aqueous media (energy barrier ≈ 20 K B T ). Also, functionalized nanowire suspension was stored in a mixture of solvents containing isopropyl alcohol, 1, 4-dioxane, and dimethyl sulfoxide maintaining stability for more than one year at the room temperature. Due to the good dispersion of the as-prepared silver nanowires in epoxy resin, increased adhesion density, reduction of air entrapment in the adhesive matrix during the curing process, and reduced oxidation rate, the as-prepared conductive adhesive with 50 wt% silver and 5 wt% polyethylene glycol showed a resistivity of 1.895 × 10-7 Ω cm.

The antigen binding fragment (Fab) is pepsin-digested product from egg yolk immunoglobulin (IgY), which shows lower immunogenicity and higher antibacterial activity. However, it limited the application of Fab due to the spontaneous adsorption and aggregation at the air-liquid interface. The present work is to investigate the effect of surfactants polysorbate 20 (PS20), poloxamer 188 (P188), and polyethylene glycol (PEG) on the aggregation stability of Fab of IgY. The results confirmed the positive role of surfactants in improving Fab stability. PS20 could effectively prevent the generation of Fab aggregates (DLS and light-obscuration analysis). It could also distinctly increase the internal hydrophobicity level, fortify the surface charge by altering the molecular conformational characteristics of Fab. The results of CLSM and surface tension demonstrated that P188 and PEG were co-adsorbed with Fab at the air-liquid interface and inhibited the formation of aggregation. PS20 competitively adsorbed in the gap between Fab molecules to inhibit the formation of aggregates. These findings would give an in-depth understanding of protein aggregation behavior influenced by surfactants and provide a theoretical basis for the development of functional food based on Fab active fragments.

We apply silver nanoparticles (Ag NPs) as catalysts of CO2 reduction in a zero-gap gas-flow electrolyser. Ag NPs stabilized by different ligands —branched polyethylenimine (BPEI), polyvinylpyrrolidone (PVP), polyethylene glycol (PEG), and citrate— are used in the experiments. The as-prepared NPs have almost identical initial size distributions, yet their catalytic performance, in terms of achievable current and CO selectivity, is different. During electrolysis all Ag NPs exhibit unambiguous morphology changes; the degradation pathway they follow, however, markedly depends on the chemical nature of the capping agent stabilizing them. Scanning electron micrographs obtained before and after constant-charge electrolyses carried out at different potentials reveal that amongst the studied ligands, BPEI seems to be the most effective stabilizer of Ag NPs; in turn, however, BPEI also limits CO formation the most. In case of PVP, mostly corrosion (particle shrinkage) is observed at practically relevant electrolysing potentials, while the application of PEG leads more to particle coalescence. Ostwald ripening seems to appear only at high applied (H2 forming) potentials in case of the three afore-mentioned ligands while in case of citrate it becomes significant already at mild (CO forming) voltages. By studying the effects of capping agent removal and exchange we demonstrate that apart from ligands directly attached to the Ag NPs, also the excess of capping agents (adsorbed on the electrode surface) plays a decisive role in determining the extent and mode of catalyst degradation. The results of SEM-based particle sizing are also confirmed by synchrotron based wide-angle X-ray scattering measurements that provide further insight into the evolution of crystallite size and lattice strain in the applied Ag NPs during electrolysis.

Graft phase change materials (GPCMs) networks with pendent side chains of phase change component trend to simultaneously enhance the encapsulation fraction and latent heat efficiency, leading to ultrahigh latent heat, compared to backbone phase change materials (BPCMs) networks with skeleton chains of phase change component. Herein, the GPCMs networks containing graft polyethylene glycol (PEG)-based side chains were synthesized via a facile high efficiency esterification approach between hydroxyl and anhydride as well as between resulting carboxyl and aziridine ring. The GPCMs had much higher normalized latent heat (from 122.6 kJ/g to 157.6 kJ/g) and latent heat efficiency (from 0.76 to 0.93) than BPCMs (from 79.3 kJ/g to 130.6 kJ/g and from 0.49 to 0.77) networks counterparts with various molecular weight (from 2 kDa to 20 kDa) of used PEGs. Also, GPCMs could reach experimental latent heat of 155 J/g with ultrahigh PEG weight fraction of 98.8% and high latent heat efficiency of 0.93 resulting from the promoted crystallization, while GPCMs showed good solid-solid phase change behavior, high thermal reliability and stability, which could not be realized in conventional BPCMs. The synergetic enhancement of PEG weight fraction and latent heat efficiency in GPCMs is due to the decreased non-PEG components and the existence of free molecular end of PEGs in GPCMs. The efficient strategy of constructing graft side chains of PEGs can enable an obvious increase in both PEG weight fraction and latent heat efficiency in solid-solid PCMs network, further leading to a significant increase in latent heat.

The development of low-cost and eco-friendly aqueous electrolytes with a wide voltage window is the key to achieving safe high energy density supercapacitors (SCs). In this work, a molecular crowding electrolyte is prepared by simulating the crowded environment in living cells. Ion transport in the molecular crowding electrolyte can be effectively improved via reducing the molecular weight of the crowding agent, polyethylene glycol (PEG). The results show that PEG with a molecular weight of 200 (PEG200) can significantly improve ionic conductivity while maintaining a wide voltage window. These advantages enable commercial activated carbon-based SCs to work at 2.5 V with high energy density, outstanding rate performance and good stability for more than 10, 000 cycles. On this basis, three series of molecular crowding electrolytes using sodium perchlorate, lithium perchlorate, and sodium trifluoromethanesulfonate as salts are developed, demonstrating the versatility of PEG200 for wide-voltage aqueous electrolytes.

In this study, the removal of hexavalent chromium from the aqueous solution using birds' feathers amended by polyaniline is investigated. Firstly, various bird feathers and polyaniline composites are synthesized and used in batch experiments to separate hexavalent chromium. Results show optimal performance of polyaniline and bird feathers composite in chromium removal. Among the bird's feather and polyaniline composites, the polyaniline/ostrich feathers/polyethylene glycol composite has the most optimal performance with a removal percentage of about four times more than that of activated carbon (87.36 %), at pH = 6 and the contact time of about 30 min. Analysis of cavities size as well as analysis of BET specific surface shows that specific surface area of polyaniline/ostrich feathers/polyethylene glycol composite with 36.22 m2/g is higher than other composites. Scanning electron microscope (SEM) images taken from the surface of the composites show better and more uniform coverage of polyaniline on the ostrich feather in the polyaniline/ostrich feather/polyethylene glycol composite. The XRD analysis and FTIR analysis confirm the synthesis of aniline on the resulted composite and it is declared that the structure of the achieved composite is amorphous.

Thermal energy storage using phase change materials (PCMs) plays a crucial role in solving the contradiction between energy supply and demand. In this paper, we proposed a novel approach to design a functionalized process for the matrix which was modified with polydopamine and silver nanoparticles for improving the crystallization process of polyethylene glycol (PEG) PCMs which were bound onto the surface and the interior of the mesoporous silica by adjusting the size and shape of pore systems, the hydrogen bonding force between PEG molecules and carriers. And the results suggested that the prepared supporting materials exhibited prominent chemical compatibility with PEG and a great enhancement for the thermal conductivity (34.0%) with the sequential modification of polydopamine and silver nanoparticles. The composite ss-PCMs also exhibited excellent thermal reliability after 10 thermal cycles, indicating that the emerging composite ss-PCMs had favorable potential in the practical applications.

Letrozole (LZ) is an aromatase inhibitor, which inhibits the formation of estrogens from androgens. Nanoemulsion is a liquid emulsion formulation utilized to increase solubility, bioavailability, and drug delivery to cancer cells. This study aims to improve LZ oral delivery through formulating solid nanoemulsion (SNE). Peppermint oil, tween 80, and transcutol P were used as an oil, surfactant, and co-surfactant, respectively. The optimized nanoemulsion (NE-3) was then incorporated into solid polyethylene glycol (PEG) to formulate (SNE). The optimized (NE-3), SNE-2, and the available marketed tablet have been compared. The optimized (NE-3) was selected according to specific parameters of optimum small nano-size 80 nm, PDI of 0.181, the zeta potential of-98.2, high transmittance (99.78%), optimum pH (5.6), a high percent of LZ content (99.03 ± 1.90), the relatively low viscosity of 60.2 mPa.s, and a rapid release of LZ within 30 min. NE-3 was selected to be formulated as SNE. LZ's best release rate was 80% in 5 min with a content homogeneity of 99.85 ± 0.04 for SNE-2. Zero-order kinetics is determined to have the greatest R2 values. Field emission scanning electron microscopy (FE-SEM) detected that SNE-2 was (36.75–96.64 nm) with a spherical form and no adhesion or aggregation. FT-IR showed no significant variations in position and shape of the absorption peaks between the pure drug and optimal formulation diagrams. This novel nanoemulsion technology aids in improving the solubility of poorly water-soluble drugs, particularly the SNE delivery method, which has a higher in-vitro release rate and expiration date of LZ than others.

Critical bone defects are a common yet challenging orthopedic problem. Tissue engineering is an emerging and promising strategy for bone regeneration in large-scale bone defects. The precise on-demand release of osteogenic factors is critical for controlling the osteogenic differentiation of seed cells with the support of appropriate three dimensional scaffolds. However, most of the effective osteogenic factors are biomacromolecules with release behaviors that are difficult to control. Here, the cholesterol-modified non-coding microRNA Chol-miR-26a was used to promote the osteogenic differentiation of human mesenchymal stem cells (hMSCs). Chol-miR-26a was conjugated to an injectable poly(ethylene glycol) (PEG) hydrogel through an ultraviolet (UV)-cleavable ester bond. The injectable PEG hydrogel was formed by a copper-free click reaction between the terminal azide groups of 8-armed PEG and dibenzocyclooctyne-biofunctionalized PEG, into which UV-cleavable Chol-miR-26a was simultaneously conjugated via a Michael addition reaction. Upon UV irradiation, Gel-c-miR-26a (MLCaged) released Chol-c-miR-26a selectively and exhibited significantly improved efficacy in bone regeneration compared to the hydrogel without UV irradiation and UV-uncleavable MLControl. MLCaged significantly enhanced alkaline phosphatase activity and promoted calcium nodule deposition in vitro and repaired critical skull defects in a rat animal model, demonstrating that injectable implantation with the precise release of osteogenic factors has the potential to repair large-scale bone defects in clinical practice. Statement of significance Provide a novel and practical strategy via hydrogel for efficient delivery and precisely controlled release of miRNAs into bone defect sites. The hydrogel is formed by polyethylene glycol (PEG), which is crosslinked by ‘click’ reaction. Cholesterol-modified miR-26a loading on the hydrogel is covalently patterned onto the fibers of hydrogel through a UV light-cleavable linker, which prevents undesired release of miRNA. This hydrogel could realize the controlled release of miRNA under light regulation both in vitro and in vivo, thus realize bone regeneration.

Crystalline lactose microparticles with uniform size and spherical shape are greatly desirable for various applications, but still challenging. Herein, uniform lactose microspheres with high crystallinity were fabricated via spray drying lactose/polyethylene glycol (200 Da) (PEG 200) combined with ethanol/water post-treatment process. The effects of feed solution composition and ethanol/water volume ratio on particle size, morphology, density, crystal property and hygroscopicity were investigated. The obtained spherical lactose/PEG 200 microparticles were partially crystallized (30-50%), exhibiting dominant crystal forms of anhydrous Lα and Lβ. After removing PEG 200 by ethanol/water, the resulting microparticles remained uniform and spherical with enhanced crystallinity (92.90 ± 1.40%), high Lα·H2O content (68.57%) and ultra-low hygroscopicity (0.29%). Possible mechanism of “micro-zone competitive dissolution-reprecipitation” was proposed to reveal the influence of PEG 200 and ethanol/water volume ratio on promoting crystallinity and maintaining spherical morphology of lactose microparticles. This work provides a promising and up-scalable way to manufacture spherical crystalline microparticles.

Compared with physical drug-loaded nanocarriers, polymeric prodrug micelles have many advantages such as high drug loading and enhanced stability in blood, so they have great potential in cancer therapy. However, these micelles have a big disadvantage, which cannot achieve long-term circulation in vivo and high absorption of tumor cells simultaneously, resulting in low administration efficiency and poor therapeutic effect on cancer. To solve problems of traditional polymeric prodrug micelles, novel polymeric micelles with tumor microenvironment response were designed in this work. The prodrug formed by covalently linking D-α-tocopherol polyethylene glycol succinate (TPGS3350), peptide (Pep), and doxorubicin (DOX) (TPGS3350-Pep-DOX) was self-assembled into micelles by encapsulating DOX physically. When the micelles entered the tumor tissue, the long-chain polyethylene glycol (PEG) was sensitively cut by the matrix metalloproteinase 2/9 (MMP2/9) enzyme, exposing the targeting molecule folate, then it entered the cell through the endocytic pathway mediated by the folate receptor. The drug loading content, encapsulation efficiency, critical micelle concentration, and invitro release of the micelles invented in this study were measured to characterize their properties. The particle size and zeta potential of micelles were characterized by dynamic light scattering. Images were scanned by transmission electron microscopes. In vitro cytotoxicity, cellular uptake, and in vivo antitumor effect evaluation experiments were measured to show that smart micelles have made much progress in material chemistry and drug delivery, making it possible to apply a stimulus–response carrier drug delivery system in clinical application.

A novel porous nanocomposite, cross-linked chitosan and polyethylene glycol (PEG) bead-supported MnFe2O4 nanoparticles (CPM), was developed as an efficient adsorbent to remove metalloid (As(III)) and heavy metals (Cd(II), Cu(II), and Pb(II)). The characteristics of CPM showed a porous structure, well dispersed MnFe2O4, and several of hydroxyl and amino groups ( OH, NH2). Batch experiments demonstrated that the best adsorption property of As(III), Cd(II), Cu(II), and Pb(II) was achieved within 8 h with maximum adsorption capacities of 9.90, 9.73, 43.94, and 11.98 mg/g, respectively. Competitive and synergistic effects (particularly precipitation) were included in the co-adsorption mechanism of As(III) and heavy metals. Thereinto, As(III) was partly oxidized by MnFe2O4 to As(V), and both were coordinated on MnFe2O4 nanoparticles. Pb(II) could also bind to MnFe2O4 by ion exchange and electrostatic attraction. Furthermore, Cd(II) and Cu(II) tended to be coordinated on chitosan. Therefore, CPM can serve as a remediation material for water and soil co-contaminated with As(III) and heavy metals.

A new rod-shaped MoO3-x@YF3:Yb3+,Er3+ integrated carrier for the NIR-II fluorescence imaging and chemotherapy has been successfully prepared by introducing the local surface plasmon resonance (LSPR) effect and regulating the morphology and surface state. The analysis methods such as XRD, SEM, EDX, TEM, UV–Vis-NIR, PL and IR are used to study the structure, morphology, composition and properties. XRD, SEM and TEM analysis shows that the surface of MoO3-x is successfully coated with YF3:Yb3+, Er3+ nanocrystals of well-crystallized orthogonality, and the carrier obtained has a unique rod-like morphology. XPS analysis shows that Mo element exists in two valence states: Mo (VI) and Mo (V). Furthermore, PL analysis shows that the carrier has stronger luminescence intensity of up-conversion and the near-infrared second region (NIR II) under the excitation of 980 nm and 1540 nm, respectively. The drug delivery capacity and release effect of carrier are studied by using doxorubicin (DOX) as an anti-tumor template drug. The results shows that the carrier with unmodified polyethylene glycol (PEG) has strong drug loading capacity and release effect. The cytotoxicity of the carrier is performed using Hela cells. The result show that the cytotoxicity was obviously related to the concentration of MoO3-x@YF3:Yb3+,Er3+ nanoparticles. This work will solve the bottleneck of fluorescence imaging of visual drug delivery carriers, tumor penetration rate and efficient drug delivery.

Pegloticase is an enzyme used to reduce serum uric acid levels in patients with chronic, treatment-refractory gout. Clinically, about 40% of patients develop high titers of anti-PEG antibodies (APA) after initial treatment, which in turn quickly eliminate subsequent doses of pegloticase from the systemic circulation and render the treatment ineffective. We previously found that pre-infusion with high MW free PEG (40 kDa) can serve as a decoy to saturate circulating APA, preventing binding to a subsequently administered dose of PEG-liposomes and restoring their prolonged circulation in mice, without any detectible toxicity. Here, we investigated the use of 40 kDa free PEG to restore the circulation of radio-labeled pegloticase in mice using longitudinal Positron Emission Tomography (PET) imaging over 4 days. Mice injected with pegloticase developed appreciable APA titers by Day 9, which further increased through Day 14. Compared to naive mice, mice with pegloticase-induced APA rapidly cleared 89Zr-labeled pegloticase, with ~75% lower pegloticase concentrations in the circulation at four hours after treatment. The 96-h AUC in APA+ mice was less than 30% of the AUC in naive mice. In contrast, pre-infusion of free PEG into PEG-sensitized mice restored the AUC of pegloticase to ~80% of that seen in naive mice, resulting in a similar biodistribution to pegloticase in naive mice over time. These results suggest that pre-infusion of free PEG may be a promising strategy to enable the safe and efficacious use of pegloticase and other PEGylated drugs in patients that have previously failed therapy due to induced APA.

Nanoparticles (NPs) have shown potential in cancer therapy, while a single administration conferring a satisfactory outcome is still unavailable. To address this issue, the dissolving microneedles (DMNs) were developed to locally deliver functionalized NPs with combined chemotherapy and photothermal therapy (PTT). α-Tocopheryl polyethylene glycol succinate (TPGS)/hyaluronic acid (HA) dual-functionalized PLGA NPs (HD10 NPs) were fabricated to co-load paclitaxel and indocyanine green. HD10 NPs significantly enhanced the cytotoxicity of low-dose paclitaxel because of active and mitochondrial targeting by HA and TPGS, respectively. PTT could further sensitize tumor cells toward chemotherapy by promoting apoptosis into the advanced period, highly activating caspase 3 enzyme, and significantly reducing the expression of survivin and MMP-9 proteins. Further, the anti-tumor effects of HD10 NPs delivered through different administration routes were conducted on the 4T1 tumor-bearing mice. After a single administration, HD10 NPs delivered with DMNs showed the best anti-tumor effect when giving chemotherapy alone. As expected, the anti-tumor effect was profoundly enhanced after combined therapy, and complete tumor ablation was achieved in the mice treated with DMNs and intra-tumor injection. Moreover, DMNs showed better safety due to moderate hyperthermia. Therefore, the DMNs along with combined chemo-photothermal therapy provide a viable treatment option for superficial tumors., Graphical abstract Dissolving microneedles encapsulating TPGS/HA functionalized PLGA nanoparticles provide a highly efficient local treatment for superficial tumor by integrating chemotherapy and photothermal therapy (PTT). The functionalized nanoparticles significantly enhanced the cytotoxicity, and sensitized tumor cells toward chemotherapy through multiple pathways.Image 1

Sulpiride (SUL), a benzamide derivative, acts as a multitarget drug with extensive biological properties. However, being a P-glycoprotein efflux substrate with a limited oral bioavailability imposes a challenge to its clinical efficacy. The current research explores the impact of tailored hybrid lipid-polysaccharide nanocomposites in augmenting the biological performance of SUL. Chitosan-graft-tocopherol polyethylene glycol 1000 succinate (TPGS) copolymers were synthesized and integrated as a polysaccharide shell into a SUL-loaded lipid nanocore. The optimized nanohybrids revealed a nanocore-shell structure with 110.1 nm particle size, 23.7 mV zeta potential, 85.42% encapsulation efficiency, a pH-dependent-release profile, and an acceptable mucoadhesive tendency. Employing TPGS into the chitosan backbone alleviated the cellular internalization of nanohybrids into the Caco-2 intestinal cells and hence increased the intestinal permeation and the oral bioavailability of SUL by 3.3, and 8.7-folds, respectively. Reserpine-induced depression rat model confirmed the superior antidepressant activity of nanohybrids, compared with free SUL and a marketed product. The nanohybrids exhibited 1.87- and 1.47-folds enhancement in both serotonin and dopamine levels, respectively. Additionally, nanohybrids were shown to attenuate brain oxidative stress state and SUL irritant effect on different body tissues. Overall, the newly tailored nanohybrids pave the way for an advance in the field of oral drug delivery.

Dense alumina ceramics were additively manufactured efficiently through a 3D gel printing process. Hydroxyethyl cellulose (HEC) was applied to ensure the printability and rigid of the gel made from boehmite. A multi-step liquid desiccant drying method was implemented to improve the drying efficiency. The results showed that the solid loading and HEC addition were two useful parameters for adjusting the rheology properties of the gel to make it suitable for 3D printing. With polyethylene glycol(PEG) added as liquid desiccants, the printed bodies with section size of 10 mm could be dried within 26 h during which the deformation and crack formation was avoided despite a high linear shrinkage of 45 % was encountered. The successful preparation of dense monolithic alumna ceramics parts with an average grain size of 1 μm, 99 % of the theoretical density and a flexural strength of 380 ± 45 MPa indicated the potential of this process.

During the past decades, amphiphilic hydrogels found versatile applications in biomaterial field due to their suitable mechanical properties and control on releasement of hydrophobic substrates. Polyethylene glycol (PEG) and polycaprolactone (PCL) are FDA approved polymers that were used together in lots of research articles due to their complementary properties. This review focused on synthetic methods, physical, and mechanical properties as well as sol–gel-sol phase transition behavior of amphiphilic hydrogels based on polyethylene glycol (PEG) and polycaprolactone (PCL). Physical hydrogels were formed base on the hydrophobic interaction between copolymers of PCL and PEG or based on supramolecular chemistry. Also, chemical hydrogels synthesized via free radical crosslinking and chemical coupling reaction between functionalized prepolymers. Both types of physical and chemical hydrogels are biocompatible and biodegradable. Physical hydrogels are thermo-sensitive and were used as injectable hydrogels that can be sensitive to pH or other triggers. In addition, chemical hydrogels could be used as tissue scaffolds according to their mechanical properties.

The objectives of the experiment were to study the effects of adding polyethylene glycol (PEG) to steer ration containing high sorghum tannins on rumen fermentation, nutrient digestion, nitrogen (N) balance and plasma biochemical parameters. Eight growing steers at 16 months of age were allotted to a replicated 4 × 4 Latin square design with 4 treatments and 4 periods (19 d each). Polyethylene glycol at 0, 1.75, 3.50 and 7.00 g/kg dry matter (DM) were added to a basal ration containing 27.82% DM of sorghum grain (total tannins 3.3 g/kg DM) as the treatments. The results indicated that adding PEG quadratically increased the ruminal pH (P = 0.049), tended to linearly increase the ruminal concentration of total volatile fatty acids (P = 0.070), increased the molar proportion of acetate (P = 0.016), linearly decreased the molar proportion of butyrate (P = 0.015), and tended to increase the molar proportion of iso-valerate (P = 0.061) and the ruminal concentration of ammonia N (P = 0.092). Adding PEG tended to quadratically decrease the relative abundance of methanogenic archaea (P = 0.082), linearly decreased the relative abundance of Fibrobacter succinogenes (P = 0.008) and decreased the relative abundance of Butyrivibrio fibrisolvens (P = 0.048) at 7.00 g/kg DM. Dietary addition with PEG increased the crude protein (CP) digestibility (P 0.05). It was concluded that adding PEG effectively improved the CP digestibility of the ration containing high sorghum tannins but increased the urinary urea excretion without improving the N retention and N retention rate in steers.

Eco-friendly methods for extraction of phycocyanins (C-PC and A-PC) from dry biomass of Spirulina platensis were carried out employing nanoparticles (NP), polyethylene glycol (PEG) and salts. There are practically no reports on such methods of extraction of phycocyanins from S. platensis. Standardization of process parameters such as concentration of NP/salt/PEG, extraction time, temperature and solvent was carried out for all the methods employed to achieve maximum productivity (yield and purity). The standardized conditions for NP, salt and PEG based extractions were observed to be 10 μg/mL, 3 mg/mL and 10% w/w concentration, respectively, phosphate buffer as an extraction solvent, 160 min of extraction time and 35 °C of extraction temperature. Silver nanoparticles based extraction resulted in the highest yield (47.68 and 34.18 mg/g db) and purity (0.98 and 0.33) of C-PC and A-PC, respectively. These results are among the highest reported in the primary extraction (itself) without any additional field intervention or process aids.

Using molecular dynamics simulations, we describe how crowded environments affect the internal dynamics and diffusion of the hepatitis C virus proteases NS3/4A. This protease plays a key role in viral replication and is successfully used as a target for antiviral treatment. The NS3 enzyme requires a peptide cofactor, called NS4A, with its central part interacting with the NS3 β-sheet, and flexible, protruding terminal tails that are unstructured in water solution. The simulations describe the enzyme and water molecules at atomistic resolution, whereas crowders are modeled via either all-atom or coarse-grained models to emphasize different aspects of crowding. Crowders reflect the polyethylene glycol (PEG) molecules used in the experiments to mimic the crowded surrounding. A bead-shell model of folded coarse-grained PEG molecules considers mainly the excluded volume effect, whereas all-atom PEG models afford more protein-like crowder interactions. Circular dichroism spectroscopy experiments of the NS4A N-terminal tail show that a helical structure is formed in the presence of PEG crowders. The simulations suggest that crowding may assist in the formation of an NS4A helical fragment, positioned exactly where a transmembrane helix would fold upon the NS4A contact with the membrane. In addition, partially interactive PEGs help the NS4A N-tail to detach from the protease surface, thus enabling the process of helix insertion and potentially helping the virus establish a replication machinery needed to produce new viruses. Results point to an active role of crowding in assisting structural changes in disordered protein fragments that are necessary for their biological function.

Hypothesis Interaction of cellular membranes with biointerfaces is of vital importance for a number of medical devices and implants. Adhesiveness of these surfaces and cells is often regulated by depositing a layer of bovine serum albumin (BSA) or other protein coatings. However, anomalously large separations between phospholipid membranes and the biointerfaces in various conditions and buffers have been observed, which could not be understood using available theoretical arguments. Methods Using the Lifshitz theory, we here evaluate the distance-dependent Hamaker coefficient describing the dispersion interaction between a biointerface and a membrane to understand the relative positioning of two surfaces. Our theoretical modeling is supported by experiments where the biointerface is represented by a glass substrate with deposited BSA and protein layers. These biointerfaces are allowed to interact with giant unilamellar vesicles decorated with polyethylene glycol (PEG) using PEG lipids to mimic cellular membranes and their pericellular coat. Results We demonstrate that careful treatment of the van der Waals interactions is critical for explaining the lack of adhesiveness of the membranes with protein-decorated biointerfaces. We show that BSA alone indeed passivates the glass, but depositing an additional protein layer on the surface BSA, or producing multiple layers of proteins and BSA results in repulsive dispersion forces responsible for 100 nm large equilibrium separations between the two surfaces.

The fluorescent properties of cadmium telluride (CdTe) containing quantum dots (QDs) have led to novel products and applications in the ink and pigment industry. The toxic effects of the emissions associated to the use of printing ink containing CdTe QDs might differ from those of conventional formulations which do not integrate nanoparticles, as CdTe QDs might be emitted. Within this work, the airborne emissions of a water-soluble fluorescent ink containing polyethylene glycol (PEG)-coated CdTe QDs of 3-5 nm diameter have been characterized and studied under controlled conditions during household inkjet printing in a scenario simulating the use phase. Subsequently, the cytotoxicological potential of atomized CdTe QDs ink in an acute exposure regimen simulating an accidental, worse-case scenario has been evaluated in vitro at the air-liquid interface (ALI) using the pulmonary cell line BEAS-2B. Endpoints screened included cell viability, oxidative stress and inflammatory effects. We have observed that CdTe QDs ink at 54.7 ng/mL decreased cell viability by 25.6 % when compared with clean air after 1h of exposure; a concentration about 65 times higher was needed to observe a similar effect in submerged conditions. However, we did not observe oxidative stress or inflammatory effects. The present study integrates the development of scenarios simulating the use phase of nano-additivated inks and the direct cell exposure for in vitro effects assessment, thus implementing a life-cycle oriented approach in the assessment of the toxicity of CdTe QDs.

Background Low temperature bonding is the key for developing advanced electronic packaging technique. While Cu is regarded as a promising material for interconnects with high conductivity, the oxidation issue during processing needs to be solved. Methods In this study, Cu-to-Cu direct bonding was achieved at low temperature without applying pressure by a green chemical method. Synthesized Cu nanoparticles (NPs) without capping agents were mixed with polyethylene glycol (PEG). Significant findings An iterating mechanism is proposed as Cu oxide catalyzing the decomposition of PEG, and the decomposed products further reduce the Cu oxide. Particle size and size distribution of Cu NPs were simply controlled by pH value of the reducing solution. A random close packing model proves that packing density of the pre-sintered Cu NPs directly correlates to bonding strength. Ductile fracture surface confirms the realization of well-sintered joints by a green process that can be applied to devices.

Bimetallic nanoparticles allow new and synergistic properties compared to the monometallic equivalents, often leading to unexpected results. Here we present on silver-iron nanoparticles coated with polyethylene glycol, which exhibit a high transverse relaxivity (316 ± 13 mM-1s−1, > 3 times that of the most common clinical benchmark based on iron oxide), excellent colloidal stability and biocompatibility in vivo. Ag-Fe nanoparticles are obtained through a one-step, low-cost laser-assisted synthesis, which makes surface functionalization with the desired biomolecules very easy. Besides, Ag-Fe nanoparticles show biodegradation over a few months, as indicated by incubation in the physiological environment. This is crucial for nanomaterials removal from the living organism and, in fact, in vivo biodistribution studies evidenced that Ag-Fe nanoparticles tend to be cleared from liver over a period in which the benchmark iron oxide contrast agent persisted. Therefore, the Ag-Fe NPs offer positive prospects for solving the problems of biopersistence, contrast efficiency, difficulties of synthesis and surface functionalization usually encountered in nanoparticulate contrast agents.

Complex oxides on the basis of LaMnO3±y were obtained via combustion of precursors containing nitrates and soluble organic agents (polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamide, polyethylene glycol, cellulose; glycine, glycerine and citric acid). The phenomenon of charge generation processes during the synthesis was analysed by measuring the potential difference between the ground and precursor. It was proposed that one of the main factors determining the processes of charge generation is the release of gaseous molecular charged particles into the environment. The maximum value of generated charges was fixed for polyvinyl alcohol containing precursors and the lowest for glycine containing ones. The composition of the initial precursors (used organic component and the ϕ value) effects the maximum temperature achieved during synthesis (300 °C–1100 °C), concentration of released gases (50–600 ppm (CO), 250–2800 ppm (NO)) and the potential difference between the ground and precursor. The dependence of specific surface area (7.5–21 m2/g), the temperature of the beginning of the intense sintering (750 °C–1150 °C) and the maximum achievable shrinkage (5–21%) on the value of measured potential difference in precursors was shown. The established regularities allow expanding ability for the production of complex oxide materials with the specified properties.

Embargado hasta 09/04/2023 Polymersomes and related self-assembled nanostructures displaying Aggregation-Induced Emission (AIE) are highly relevant for plenty of applications in imaging, biology and functional devices. Experimentally simple, scalable and universal strategies for on-demand self-assembly of polymers rendering well-defined nanostructures are highly desirable. A purposefully designed combination of amphiphilic block copolymers including tunable lengths of hydrophilic polyethylene glycol (PEGm) and hydrophobic AIE polymer poly(tetraphenylethylene-trimethylenecarbonate) (P(TPE-TMC)n) has been studied at the air/liquid interface. The unique 2D assembly properties have been analyzed by thermodynamic measurements, UV-vis reflection spectroscopy and photoluminescence in combination with molecular dynamics simulations. The (PEG)m-b-P(TPE-TMC)n monolayers formed tunable 2D nanostructures self-assembled on demand by adjusting the available surface area. Tuning of the PEG length allows to modification of the area per polymer molecule at the air/liquid interface. Molecular detail on the arrangement of the polymer molecules and relevant molecular interactions has been convincingly described. AIE fluorescence at the air/liquid interface has been successfully achieved by the (PEG)m-b-P(TPE-TMC)n nanostructures. An experimentally simple 2D to 3D transition allowed to obtain 3D polymersomes in solution. This work suggests that engineered amphiphilic polymers for AIE may be suitable for selective 2D and 3D self-assembly for imaging and technological applications.