Polyethylene Glycol Grafting Research Articles

Antifouling activity of PEGylated chitosan coatings: Impacts of the side chain length and encapsulated ZnO/Ag nanoparticles

PEGylation is regarded as a common antifouling strategy and the effect is normally linked with surface hydrophilicity of the coatings. Herein, the biopolymer chitosan (CS) was grafted by polyethylene glycol (PEG) of different chain lengths (molecular weight 200, 4 k and 100 k Da) to verify if the hydrophilicity of CS-PEG coatings is crucial in determining antifouling activities and if PEG chain length influences biofouling in marine environment. Properties of copolymers such as melting points and crystallinity are affected by grafting PEG. The water contact angle (WCA) of CS-PEG coatings increases with the chain length of grafted PEG, from 27° to 58°. Photocatalyst of zinc oxide-silver (ZnO/Ag) was also studied and its embedment (2 % to CS-PEG) renders the surface of CS-PEG coatings more hydrophobic with WCA increased from 52° to 86°. Antibacterial, anti-diatom, and anti-biofilm activities of the coatings were evaluated in natural sea water. The bacterial density on CS-PEG coatings was dramatically reduced to 4 × 104 compared to the control of 7 × 104 ind/mm2, and further to 2 × 104 for CS-PEG-ZnO/Ag coatings. CS-PEG coatings also strongly inhibit diatoms (120–200 ind/mm2), but the inclusion of ZnO/Ag did not obviously enhance such effect (50–150 ind/mm2). The findings provide useful insights for designing polymer-based antifouling coatings.

SEPS functionalized PEG copolymer for improved toughness without obvious plasticization in epoxy resin

AbstractThe effects of grafting level of polyethylene glycol (PEG) grafted styrene ethylene propylene styrene (SEPS) on the intrinsic brittleness of epoxy thermosets were studied. The SEPS‐g‐PEG block copolymer (BCP) was synthesized by grafting various grafting degree of PEG (i.e., 10%, 20%, 30%, and 40%) on polystyrene (PS) blocks of SEPS following Williamson ether synthesis method. A total of 10 wt% of the BCP modifiers were dispersed in epoxy thermosets. PEG side chains were miscible in the epoxy which formed a uniform BCP dispersion within the epoxy thermoset matrix. As the degree of PEG grafting was increased, the BCP phase was absorbed in the epoxy matrix. This absorption occurred because the increase in PEG grafting provided more miscible PEG chains to bind the BCP and epoxy nanostructures together. The differential scanning calorimeter and dynamic mechanical thermal analysis analyses indicated that BCP toughened epoxy exhibited an improved glass transition temperature (Tg). At a 40% PEG grafting degree in the BCP, the critical stress intensity factor (KIC) and critical strain energy release rate (GIC) increased up to 80% and 180%, respectively. This trend suggested that the energy associated with fractures could be absorbed through the deformation of the softer phases when a load was applied to them.

Improved Properties of Poly (Methyl Methacrylate) Grafted Polyethylene Glycol for Ocular Prosthetics Applications

Improved Properties of Poly (Methyl Methacrylate) Grafted Polyethylene Glycol for Ocular Prosthetics Applications

An insect sclerotization-inspired antifouling armor on biomedical devices combats thrombosis and embedding

Thrombus formation and tissue embedding significantly impair the clinical efficacy and retrievability of temporary interventional medical devices. Herein, we report an insect sclerotization-inspired antifouling armor for tailoring temporary interventional devices with durable resistance to protein adsorption and the following protein-mediated complications. By mimicking the phenol-polyamine chemistry assisted by phenol oxidases during sclerotization, we develop a facile one-step method to crosslink bovine serum albumin (BSA) with oxidized hydrocaffeic acid (HCA), resulting in a stable and universal BSA@HCA armor. Furthermore, the surface of the BSA@HCA armor, enriched with carboxyl groups, supports the secondary grafting of polyethylene glycol (PEG), further enhancing both its antifouling performance and durability. The synergy of robustly immobilized BSA and covalently grafted PEG provide potent resistance to the adhesion of proteins, platelets, and vascular cells in vitro. In ex vivo blood circulation experiment, the armored surface reduces thrombus formation by 95 %. Moreover, the antifouling armor retained over 60 % of its fouling resistance after 28 days of immersion in PBS. Overall, our armor engineering strategy presents a promising solution for enhancing the antifouling properties and clinical performance of temporary interventional medical devices.

An energy storage composite using cellulose grafted polyethylene glycol as solid–solid phase change material

AbstractPhase‐change material (PCM) has great thermal energy ability, which has been used as building material for energy conservation. While the most widely used solid–liquid PCM usually appeared leakage during the phase change transition. In order to overcome the leakage of solid–liquid PCM and prepare a viable building energy‐saving materials for indoor temperature regulation, thermal energy storage composites were prepared by utilizing cellulose grafted PEG as phase change material (PCM) and high‐density polyethylene (HDPE) as the substrate. The liquid leakage of PEG was solved after graft to fabricate solid–solid PCM. HDPE is beneficial for solving the leakage and improving the mechanical property by its secondary encapsulation. The synthesized Cellulose‐PEG was characterized by scanning electron microscopy (SEM), X‐ray diffractometer (XRD), and differential scanning calorimetry (DSC). Thermal and mechanical characteristics of the composite were explored. The outcomes revealed that: (1) PEG was successfully grafted to the surface of cellulose and Cellulose‐PEG showed solid–solid phase change behavior. (2) Both the melting‐cooling temperatures and the thermal stability of solid–solid wood plastic composite (SSWPC) had the potential as thermal energy storage material for temperature regulating. (3) The addition of Cellulose‐PEG adversely affected moisture resistance, flexural property, and impact strength due to the weak interface bonding. The physical and mechanical degradation was tolerable for applying situation where mechanical performance is less crucial.Highlights Cellulose‐PEG showed solid–solid phase change behavior without liquid leakage. High‐density polyethylene (HDPE) was used as the matrix to realize the second encapsulation of PCM. Cellulose‐PEG negatively influenced the physical and mechanical property of HDPE. Solid–solid wood plastic composite presented great thermal storage capacity for indoor temperature regulating.

Excipient-free lyophilization of block copolymer micelles for potential lung surfactant therapy applications

Polymer lung surfactant (PLS) is a polyethylene glycol (PEG)-brushed block copolymer micelle designed for pulmonary surfactant replacement therapy. Saccharides (e.g., sucrose and (2-hydroxypropyl)-β-cyclodextrin) and water-soluble polymers (e.g., PEG), common excipients for lyophilization, were found to severely impair the surface activity of lyophilized PLS. To investigate the feasibility of excipient-free lyophilization of PLS, we studied the effects of both PLS material parameters and lyophilization operating parameters on the redispersibility and surface availability of reconstituted PLS, all without relying on excipients. We found that the redispersibility was improved by three factors; a faster cooling rate during the freezing stage reduced freezing stress; a higher PEG grafting density enhanced dissipating effects; and the absence of hydrophobic endgroups in the PEG block further prevented micelle aggregation. Consequently, the surface availability of PLS increased, enabling the micelle monolayer at the air/water interface to achieve a surface tension below 10 mN/m, which is a key pharmaceutical function of PLS. Moreover, the lyophilized micelles in powder form could be easily dispersed on water surfaces without the need for reconstitution, which opens up the possibility of inhalation delivery, a more patient-friendly administration method compared to instillation. The successful excipient-free lyophilization unlocks the potential of PLS for addressing acute respiratory distress syndrome (ARDS) and other pulmonary dysfunctions.

One-Step Bulk-Suspension Polymerization of Polyethylene Glycol-Based Copolymer Microspheres for Phase Change Textiles.

The paper presents a feasible strategy through one-step bulk-suspension polymerization, grafting PEG onto an in situ synthesized copolymer. In more detail, PEG was grafted onto a homemade polystyrene/maleic anhydride copolymer (SMA) via bulk-suspension polymerization with poly(vinyl alcohol) as a suspending agent. According to the optimal reaction conditions, the grafting rate of PEG was 56.2% through chemical titration experiments. At the same time, the quantitative relationship between the grafting rate and enthalpy was demonstrated for the first time in a PEG-based solid-solid phase change material (S-SPCM). Morphology observation revealed that the obtained S-SPCM is made up of white microspheres of approximately 100-150 μm. The powdery product polystyrene/maleic anhydride grafted polyethylene glycol (SMA-g-PEG) obtained through bulk-suspension polymerization endowed that the whole product could be used directly as a phase change material without postprocessing. The melting enthalpy and crystallization enthalpy of SMA-g-PEG were 79.3 J/g and 76.9 J/g, respectively. Based on the effective fixed load of PEG, the macrostructure of SMA-g-PEG was almost unchanged at 70 °C compared with the macrostructures at 20 °C, and the latent heat of SMA-g-PEG was decreased slightly after 1000 thermal cycles. Overall, the obtained SMA-g-PEG can be used as a filler in insulation materials and composited with fibers to obtain phase change thermoregulated smart textiles.

In silico prediction of protein binding affinities onto core-shell PEGylated noble metal nanoparticles for rational design of drug nanocarriers.

Polymer-coated nanoparticles (NP) are commonly used as drug carriers or theranostic agents. Their uptake rates are modulated by the interactions with essential serum proteins such as transferrin and albumin. Understanding the control parameters of these interactions is crucial for improving the efficiency of these nanoscale devices. In this work, we perform a multiscale computational study of protein adsorption onto polyethylene glycol (PEG) coated gold and silver NPs, producing protein-NP adsorption rankings as a function of PEG grafting density, which are validated against previously reported experimental protein-NP binding constants. Furthermore, the applied nano-docking method provides information on the preferred orientation of proteins immobilised on the surface of NPs. We propose a method of construction of model core-shell NPs in silico. The presented protocol can provide molecular level insights for the experimental development of biosensors, nanocarriers, or other nanoplatforms where information on the preferred orientation of protein at the bio-nano interface is crucial, and enables fast in silico prescreening of assays of various nanocarriers, i.e., combinations of proteins, NPs, and coatings.

Study of Cytotoxicity and Internalization of Redox-Responsive Iron Oxide Nanoparticles on PC-3 and 4T1 Cancer Cell Lines.

Redox-responsive and magnetic nanomaterials are widely used in tumor treatment separately, and while the application of their combined functionalities is perspective, exactly how such synergistic effects can be implemented is still unclear. This report investigates the internalization dynamics of magnetic redox-responsive nanoparticles (MNP-SS) and their cytotoxicity toward PC-3 and 4T1 cell lines. It is shown that MNP-SS synthesized by covalent grafting of polyethylene glycol (PEG) on the magnetic nanoparticle (MNP) surface via SS-bonds lose their colloidal stability and aggregate fully in a solution containing DTT, and partially in conditioned media, whereas the PEGylated MNP (MNP-PEG) without S-S linker control remains stable under the same conditions. Internalized MNP-SS lose the PEG shell more quickly, causing enhanced magnetic core dissolution and thus increased toxicity. This was confirmed by fluorescence microscopy using MNP-SS dual-labeled by Cy3 via labile disulfide, and Cy5 via a rigid linker. The dyes demonstrated a significant difference in fluorescence dynamics and intensity. Additionally, MNP-SS demonstrate quicker cellular uptake compared to MNP-PEG, as confirmed by TEM analysis. The combination of disulfide bonds, leading to faster dissolution of the iron oxide core, and the high-oxidative potential Fe3+ ions can synergically enhance oxidative stress in comparison with more stable coating without SS-bonds in the case of MNP-PEG. It decreases the cancer cell viability, especially for the 4T1, which is known for being sensitive to ferroptosis-triggering factors. In this work, we have shown the effect of redox-responsive grafting of the MNP surface as a key factor affecting MNP-internalization rate and dissolution with the release of iron ions inside cancer cells. This kind of synergistic effect is described for the first time and can be used not only in combination with drug delivery, but also in treatment of tumors responsive to ferroptosis.

Photosensitivity of Different Nanodiamond-PMO Nanoparticles in Two-Photon-Excited Photodynamic Therapy.

In addition to their great optical properties, nanodiamonds (NDs) have recently proved useful for two-photon-excited photodynamic therapy (TPE-PDT) applications. Indeed, they are able to produce reactive oxygen species (ROS) directly upon two-photon excitation but not with one-photon excitation; Methods: Fluorescent NDs (FNDs) with a 100 nm diameter and detonation NDs (DNDs) of 30 nm were compared. In order to use the gems for cancer-cell theranostics, they were encapsulated in a bis(triethoxysilyl)ethylene-based (ENE) periodic mesoporous organosilica (PMO) shell, and the surface of the formed nanoparticles (NPs) was modified by the direct grafting of polyethylene glycol (PEG) and amino groups using PEG-hexyltriethoxysilane and aminoundecyltriethoxysilane during the sol-gel process. The NPs' phototoxicity and interaction with MDA-MB-231 breast cancer cells were evaluated afterwards; Results: Transmission electronic microscopy images showed the formation of core-shell NPs. Infrared spectra and zeta-potential measurements confirmed the grafting of PEG and NH2 groups. The encapsulation of the NDs allowed for the imaging of cancer cells with NDs and for the performance of TPE-PDT of MDA-MB-231 cancer cells with significant mortality. Multifunctional ND@PMO core-shell nanosystems were successfully prepared. The NPs demonstrated high biocompatibility and TPE-PDT efficiency in vitro in the cancer cell model. Such systems hold good potential for two-photon-excited PDT applications.

Composite Electrolytes Prepared by Improving the Interfacial Compatibility of Organic-Inorganic Electrolytes for Dendrite-Free, Long-Life All-Solid Lithium Metal Batteries.

Compared with simplex ceramic or polymer solid electrolytes, composite solid electrolyte (CSE) is more promising for its better interfacial compatibility to electrode and high ionic conductivity simultaneously. Further, the interfacial compatibility within ceramic and polymer is considered to be more and more critical to the overall performance of solid-state batteries. Avoiding the agglomeration of ceramic particles at high loadings can improve the whole intrinsic characteristic and electrochemical performance of CSEs. Herein, we designed a CSE (EO@LLZTO-PEO), which consists of composite particles (EO@LLZTO) as a filler and polyethylene oxide (PEO) as polymer matrix. EO@LLZTO was prepared by chemically grafting polyethylene glycol monomethyl ether methacrylate (MPEG-MAA) on the micro-sized Li6.4La3Zr1.4Ta0.6O12 (LLZTO) particles. By introducing of polymer containing EO segments onto LLZTO, the interfacial compatibility between LLZTO and PEO matrix is highly enhanced, and the intrinsic Li+ complexation capability of MPEG-MAA is improved, even at the high loading of garnet. EO@LLZTO-PEO shows a high ionic conductivity (1.91 mS cm-1), a broad electrochemical window (∼5.2 V vs Li/Li+), and a high lithium ion transference number (0.72). The Li/EO@LLZTO-PEO/Li battery also exhibits a long cycle stability (over 1200 h of cycling). Moreover, all-solid-state batteries with LiFePO4 and LiNi0.8Co0.1Mn0.1O2 (NCM811) cathodes exhibit excellent cycling stability and rate performance. Consequently, enhancing the interfacial compatibility between organic and inorganic electrolytes is identified to be one of the crucial strategies for commercial solid-state lithium batteries.

PVA/PEO/PVA-g-APEG nanofiber membranes with cytocompatibility and anti-cell adhesion for biomedical applications

To prepare novel medical dressings with excellent comprehensive properties, this work uses the polyvinyl alcohol-allyl polyethylene glycol graft copolymer (PVA-g-APEG) synthesized in our previous work as a modifier. The polyvinyl alcohol (PVA)/polyethylene oxide (PEO)/PVA-g-APEG nanofiber membranes with different PVA-g-APEG contents are successfully prepared by electrospinning technology. The biomimetic natural extracellular matrix structure of nanofiber membranes is achieved by regulating the PVA-g-APEG contents. As the content of PVA-g-APEG is 4 wt%, the diameter distribution of nanofibers is the narrowest. The average diameter of nanofibers reaches the minimum value of 267.18 nm, and the porosity of nanofiber membranes reaches the maximum value of 77.90%. Meanwhile, nanofiber membranes possess excellent biocompatibility. The absorption capacity of the nanofiber membranes for different liquids is improved with higher PVA-g-APEG content. The nanofiber membranes become soft and slippery after contact with liquid, effectively avoiding adhesion with cells. The cell proliferation rate is higher than 100%, and the cytotoxicity grade is 0. Additionally, the mechanisms of intermolecular interactions, crystallization and mechanical properties change of nanofiber membranes are discussed systematically. It provides a method and idea for preparing high-strength PVA/PEO nanofiber membranes and realizing the practical application of PVA/PEO composite systems in medical dressings.

Influence of Molecular Weight and Grafting Density of PEG on the Surface Properties of Polyurethanes and Their Effect on the Viability and Morphology of Fibroblasts and Osteoblasts.

Grafting polyethylene glycol (PEG) onto a polymer's surface is widely used to improve biocompatibility by reducing protein and cell adhesion. Although PEG is considered to be bioinert, its incorporation onto biomaterials has shown to improve cell viability depending on the amount and molecular weight (MW) used. This phenomenon was studied here by grafting PEG of three MW onto polyurethane (PU) substrata at three molar concentrations to assess their effect on PU surface properties and on the viability of osteoblasts and fibroblasts. PEG formed a covering on the substrata which increased the hydrophilicity and surface energy of PUs. Among the results, it was observed that osteoblast viability increased for all MW and grafting densities of PEG employed compared with unmodified PU. However, fibroblast viability only increased at certain combinations of MW and grafting densities of PEG, suggesting an optimal level of these parameters. PEG grafting also promoted a more spread cell morphology than that exhibited by unmodified PU; nevertheless, cells became apoptotic-like as PEG MW and grafting density were increased. These effects on cells could be due to PEG affecting culture medium pH, which became more alkaline at higher MW and concentrations of PEG. Results support the hypothesis that surface energy of PU substrates can be tuned by controlling the MW and grafting density of PEG, but these parameters should be optimized to promote cell viability without inducing apoptotic-like behavior.

Correction to: Novel approach in synthesizing graphene oxide grafted polyethylene glycol via Steglich esterification

Correction to: Novel approach in synthesizing graphene oxide grafted polyethylene glycol via Steglich esterification

Fabrication of polydimethylsiloxane mixed matrix membranes for recovery of ethylene glycol butyl ether from water by pervaporation

Due to its wide application as a solvent or cleaning agent in automotive paints and other coatings industries, the separation and recovery of ethylene glycol butyl ether (EB) from wastewater played a key role in reducing emissions in industries such as automotive coatings. To achieve the efficient separation of EB by pervaporation process, three different types of nanomaterials were first used as additives to construct the mixed matrix membranes (MMMs) for pervaporation using polydimethylsiloxane (PDMS) as the polymer material. The addition of three nanomaterials could improve the affinity of the resulting MMMs toward EB and accelerate the diffusion process of EB in MMMs, thus eventually enhancing the separation performance of the resulting membranes. When three nanomaterials seriously agglomerated in polymeric materials, the improvement of the EB diffusion in MMMs decreased. Moreover, the diffusion of EB molecules in the MMMs containing nanomaterials was still lower than that of water molecules due to the insufficient capturing of EB, and the diffusion selectivity of the resulting MMMs for EB was less than 1. The surface modification for nanomaterials by grafting polyethylene glycol (PEG) could enhance the affinity between PEG-grafted nanomaterials and EB molecules, which simultaneously improved the swelling performance of MMMs and the diffusion process of EB in MMMs. Owing to the stronger affinity between the PEG2000-grafted nanomaterials containing more ether groups and EB molecules, PDMS incorporated with PEG2000-grafted nanomaterials exhibited the best membrane flux (730 g m−2 h−1) and selectivity (30), which was twice that of the commercial membrane. Furthermore, the PDMS incorporated with PEG2000-grafted nanomaterials maintained excellent and stable performance for separating EB during pervaporation for 20 h, while the separation performance of the commercial membrane decreased significantly after 12 h of pervaporation experiments. Therefore, the MMMs fabricated in this work are promising candidates for the separation and recovering the ether solvents through membrane technology.

Surface modification of polycarbonate urethane by grafting polyethylene glycol and bivalirudin drug for improving hemocompatibility

AbstractAs the clinical demand for blood‐contacting materials increases, higher requirements are placed on their physicochemical properties, durability and hemocompatibility in vivo. In this work, a multiple functionalized material was developed through a facile modification process. Herein, polycarbonate urethane (PCU) surface was co‐modified with polyethylene glycol (PEG) and bivalirudin (BVLD). PCU provides excellent physical and mechanical properties, PEG and BVLD, especially BVLD, enable the surface with outstanding anticoagulant capacity. Specifically, PCU surface was first treated with hexamethylene diisocyanate to introduce active isocyanate groups onto the surface, followed by hydroxy‐PEG grafting to improve the hydrophilicity. Finally, BVLD was immobilized on the surface via Michael addition reaction to improve antithrombotic properties. Attenuated total reflection Fourier transforms infrared spectroscopy and UV spectrophotometers were used to confirm the modified surfaces. The hydrophilicity was characterized by static water contact angle measurement, the morphology of the modified surfaces was observed by scanning electron microscopy. Blood compatibility of the modified surfaces was characterized by the hemolysis rate, platelet adhesion assay and cell culture test. The results showed that the BVLD immobilized surface has excellent anticoagulant properties, good fibrin‐bound thrombin inhibition, and good resistance against non‐specific adhesion of proteins. Hence, the co‐modification with PEG and BVLD was proved an encouraging strategy for improving hemocompatibility.

Designing non-textured, all-solid, slippery hydrophilic surfaces

Slippery surfaces are sought after due to their wide range of applications in self-cleaning, drag reduction, fouling-resistance, enhanced condensation, biomedical implants etc. Recently, non-textured, all-solid, slippery surfaces have gained significant attention because of their advantages over super-repellent surfaces and lubricant-infused surfaces. Currently, almost all non-textured, all-solid, slippery surfaces are hydrophobic. In this work, we elucidate the systematic design of non-textured, all-solid, slippery hydrophilic (SLIC) surfaces by covalently grafting polyethylene glycol (PEG) brushes to smooth substrates. Furthermore, we postulate a plateau in slipperiness above a critical grafting density, which occurs when the tethered brush size is equal to the inter-tether distance. Our SLIC surfaces demonstrate exceptional performance in condensation and fouling-resistance compared to non-slippery hydrophilic surfaces and slippery hydrophobic surfaces. Based on these results, SLIC surfaces constitute an emerging class of surfaces with the potential to benefit multiple technological landscapes ranging from thermofluidics to biofluidics.

Construction of high sulfur loading electrode with functional binder of polyacrylic acid polymer grafted with polyethylene glycol for lithium/sulfur batteries

Construction of high sulfur loading is crucial for the development of high energy density lithium/sulfur batteries. The binder is indispensable for constructing high active material loading electrode. Here, cross-linked polymeric network of polyacrylic acid polymer grafted polyethylene glycol (PAA-g-PEG) as functional binder has been developed for constructing high sulfur loading electrode in lithium/sulfur batteries. The cross-linked structure of PAA-g-PEG polymer binder has enhanced the active material adhesion, mechanical properties, which decreased overpotential polarization, improved the lithium ions diffusion coefficient, and reduced the self-discharge. More importantly, the PAA-g-PEG functional binder could alleviate the expansion of high sulfur loading electrode. Due to the above advantages, the carbon nanotubes modified sulfur electrode (CNTs@S; sulfur content: 84.3%) with PAA-g-PEG binder obtains the first discharge specific capacity of 795 mAh g−1 at 2.56 mA cm−2 (0.3 C) under a sulfur loading of 5.1 mg cm−2, with a decay rate of 0.07% per cycle over 200 cycles. Even with the high sulfur loading of 9.6 mg cm−2, the CNTs@S electrode exhibits an initial area capacity of 9.5 mAh cm−2 at a current density of 1.61 mA cm−2, and the capacity retention of 97.5% over 50 cycles.

A novel biomedical compatibilizer (polyvinyl alcohol‐allyl polyethylene glycol graft copolymer) for polyvinyl alcohol/polyethylene oxide composite system

AbstractDue to biocompatibility and similar extracellular matrix structure, polyvinyl alcohol (PVA)/polyethylene oxide (PEO) nanofiber membranes are an essential medical dressing. However, the phase separation of the PVA/PEO composite system will occur within a short time. It severely limits the continuous preparation of PVA/PEO nanofiber membranes. To make PVA/PEO composite system maintain compatibility, a novel polyvinyl alcohol‐allyl polyethylene glycol (PVA‐g‐APEG) graft copolymer with phase change, compatibilization and biocompatibility was prepared successfully. Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) prove that the copolymerization and alcoholysis reaction allyl polyethylene glycol (APEG) and vinyl acetate (VAc) successfully obtained PVA‐g‐APEG graft copolymer. The prepared PVA‐g‐APEG not only has electrospinability but can effectively prevent the phase separation of PVA/PEO composite system, which ensures the continuity of electrospinning in the industry. Additionally, the feasibility of the PVA‐g‐APEG compatibilized PVA/PEO composite system for application in biomedical was verified through the preparation and various assessments of PVA‐g‐APEG/PVA/PEO nanofiber dressings. The prepared PVA‐g‐APEG is beneficial to the PVA/PEO composite system to broaden its application in biomedical and other fields.

Bioinspired Polysaccharide Derivative with Efficient and Stable Lubrication for Silicon-Based Devices.

It is becoming increasingly important to synthesize efficient biomacromolecule lubricants suitable for medical devices. Even though the development of biomimetic lubricants has made great progress, the current system suitable for hydrophobic silicone-based medical devices is highly limited. In this work, we synthesize one kind of novel polysaccharide-derived macromolecule lubricant of chitosan (CS) grafted polyethylene glycol (PEG) chains and catechol groups (CT) (CS-g-PEG-g-CT). CS-g-PEG-g-CT shows good adsorption ability by applying quantitative analysis of quartz crystal microbalance (QCM), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), and confocal fluorescence imaging technique, as well as the typical shear-thinning feature. CS-g-PEG-g-CT exhibits low and stable coefficients of friction (COFs) (0.01-0.02) on polydimethylsiloxane (PDMS) surfaces at a wide range of mass concentrations in diverse media including pure water, physiological saline, and PBS buffer solution and is even tolerant to various normal loads and sliding frequencies for complex pressurizing or shearing environments. Subsequently, systematic surface characterizations are used to verify the dynamic attachment ability of the CS-g-PEG-g-CT lubricant on the loading/shearing process. The lubrication mechanism of CS-g-PEG-g-CT can be attributed to the synergy of strong adsorption from catechol groups to form a uniform assembly layer, excellent hydration effect from PEG chains, and typical shear-thinning feature to dissipate viscous resistance. Surprisingly, CS-g-PEG-g-CT exhibits efficient lubricity on silicone-based commercial contact lenses and catheters. The current macromolecule lubricant demonstrates great real application potential in the fields of medical devices and disease treatments.