Enabling the living capability of secreting liquids dynamically triggered by external stimuli while maintaining the bulk frame is a significant challenge for mucosa‐inspired hydrogels. A ...mucosa‐inspired electro‐responsive hydrogel is developed in this study using the synergy between electro‐responsive silk fibroin supramolecular non‐covalent networks and covalent polyacrylamide and polyvinyl alcohol polymer networks. The formed supramolecular‐covalent hydrogel exhibits a partial gel‐sol transition upon the application of an electric field, and the liquid layer on the hydrogel surface near the cathode is used to mimic the mucus‐secreting capability to regulate lubrication. The electro‐responsive lubricating process can operate under a safe voltage and exhibits good reversibility. It is also a universal strategy to construct an electro‐responsive hydrogel by introducing an electro‐responsive supramolecular network into the polymer network. This mucosa‐inspired electro‐responsive supramolecular‐covalent hydrogel offers a promising method for designing soft actuators or robots that can regulate lubrication using an electric strategy.
Mucosa‐inspired electro‐responsive lubricating hydrogel is developed based on the synergy of electro‐responsive supramolecular non‐covalent silk fibroin and covalent polyacrylamide and polyvinyl alcohol polymer network. It demonstrates partial gel‐sol transition under the electric field to regulate the lubricating property.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
In situ hydrogels with rapid hemostasis and antibacterial activity have received considerable attention in the field of wound healing. Herein, a white light and NIR dual light-responsive cellulose ...nanofibril (CNF)-based in situ hydrogel wound dressing is tailored by using white light-responsive CNF and endogenous antibacterial CNF as the skeleton, Prussian blue nanoparticles, Pluronic® F127 and hydroxypropyl methyl cellulose as the NIR, temperature-responsive switch and binder, respectively. The dressing exhibits rapid hemostasis properties in rat liver injury model with low blood loss of 286.4 mg and short hemostasis time of 63 s. Meanwhile, the antibacterial activity of the dressing with white and NIR irradiation against Escherichia coli, Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA) is higher than 99.9 %. Interestingly, the dressing with biocompatibility can promote MRSA infection wound healing and can be removed on demand without secondary injury to skin. Therefore, it has promising applications for first-aid hemostasis and wound healing.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this work, a series of biodegradable triblock poly(ethylene glycol)-poly(ɛ-caprolactone)-poly(ethylene glycol) (PEG-PCL-PEG, PECE) copolymers were successfully synthesized by ring-opening ...copolymerization, and were characterized by
1H NMR, FT-IR, GPC, and DSC. Aqueous solutions of PECE copolymers underwent thermosensitive sol–gel–sol transition as temperature increases when the concentration was above corresponding critical gel concentration (CGC). Sol–gel–sol phase transition diagrams were recorded using test tube inverting method, which depended on hydrophilic/hydrophobic balance in macromolecular structure, as well as some other factors, including topology of triblock copolymers and solution composition of the hydrogel. As a result, the sol–gel–sol transition temperature range could be varied, which might be very useful for its application as injectable drug delivery systems. The
in vivo gel formation and degradation behavior was conducted by injecting aqueous PECE solution into KunMing mice subcutaneously.
In vitro degradation behavior,
in vitro drug release behavior, and cytotoxicity were also investigated in this paper. Therefore, owing to great thermosensitivity and biodegradability of these copolymers, PECE hydrogel is believed to be promising for
in situ gel-forming controlled drug delivery system.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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•Silica aerogel was successfully synthesized from fly ash acid sludge.•Effect of surface modification on the properties of silica aerogel was investigated.•The modified aerogel ...exhibited better performance than that of the unmodified aerogel.•The modified aerogel exhibited strong hydrophobicity.
The silica aerogels were synthesized using fly ash acid sludge via ambient pressure drying. The silica in the fly ash acid sludge was extracted using a NaOH solution to form the sodium silicate solution. Silica wet gels were formed by sol–gel process of the obtained sodium silicate solution. To prevent the condensation and shrinkage of the wet gel structure during drying, the surfaces of wet gel were modified using trimethylchlorosilane (TMCS) via solvent exchange and surface modification. The effects of surface modification on the textural and physical properties of the silica aerogels were investigated. The properties of the synthesized silica aerogels were analyzed with SEM, BJH, FT-IR, DTA-TG and contact angle measurement. The results indicated that the silica gel modified using TMCS could undergo reversible shrinkage during ambient pressure drying and thereby preserved mesoporous structure. The modified aerogel had much lower density (0.085g/cm3), higher specific surface area (700m2/g) and larger pore volume (3.29cc/g) than those of the unmodified aerogel. The contact angle measurements indicated that the modified aerogel had a hydrophobic property with contact angle of 140°.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
New vinylbenzene substituted imidazole based zwitterionic polymers with unique characteristics like swelling in water and solubility in concentrated brine solution in which they exhibited a ...reversible upper critical solution temperature (UCST) and gel-sol transitions are reported herein.
•Structure and drug-adaptive dynamic hydrogel simulates regenerative microenvironments to promote nerve regeneration.•Integrates sequential drug release and gel structure remodeling.•Dual ROS and ...Ca2 + responsive characteristics reshape the nerve regeneration microenvironment.•Gel-sol–gel state transitions achieve three-dimensional structure remodeling.•Dual nerve repair treatment strategy balances proximal repair promotion and inhibition of distal structural damage.
The clinical management of segmental nerve deficits faces significant challenges, particularly in achieving substantial neural structural reconstruction and functional recovery. Dynamic, adaptive smart hydrogels hold great promise for restoring tissue function by mimicking regenerative microenvironments and cytokine secretion. However, the influence of hydrogel structure on drug release behavior and its role in maintaining nerve bridging during repair remains underexplored and warrants attention. Here, we present a sequentially gel-forming nerve-guiding conduit (NC/DS@HPBGP) composed of bisphosphonates-modified hyaluronic acid (HA-PBA-BP) and Tannic acid-modified GelMA (GelMA-TA), which contains borate ester bonds and metal coordination bonds, allowing for a dual response to ROS and Ca2+ at nerve injury sites. After implantation, the conduit undergoes dynamic gel-sol–gel transitions, including ROS-responsive release of narciclasine (NC) and 5-iodoisoquinoline (DS) and Ca2+ cross-linking-induced 3D structural reorganization, resulting in enhancing nerve regeneration proximally through immunomodulation and ensuring structural integrity distally via mitochondrial autophagy. This multifaceted integration facilitates dynamic remodeling of the nerve regeneration microenvironment, markedly augmenting nerve regeneration and repair efficacy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Poly(N-acryloyl glycinamide) is a neutral polymer that can form gel–sol thermoresponsive systems with upper critical solution temperature in aqueous media. The temperature of the reversible gel–sol ...transition depends on the molar mass and the concentration of macromolecules. These parameters were combined to adjust the transition temperature slightly above body temperature for the sake of respecting living tissues during the sol form injection using a classical syringe. On contact with local tissues, the injected sol turned rapidly to a gel. The simplicity of the process makes it exploitable to administrate and deliver neutral or ionic drug and especially those that are soluble in aqueous media. The versatility was exemplified from formulations with cobalt acetate, small polymers (MW~2000g/mol), tartrazine and methylene blue dyes and albumin. The model compounds were allowed to diffuse in an isotonic pH=7.4 buffered medium at 37°C. All the release profiles were typical of diffusion control with 100% release within 2 to 3weeks and no obvious burst. The in vitro release of methylene blue from a gel formulation was checked prior to injection in the peritoneal cavity of mice where the release of the dye was monitored visually through tissue and organ colorations. A comparable polymer-free dye solution was used as control. Coloration appeared rapidly in tissues and organs and it was still detectable 52h post injection of the gel whereas it was no longer present at 24h in control mice.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
A hexaazatriphenylene (HAT)-based gelator was developed. It exhibits excellent gelation ability. The resulting organogel shows very high selectivity toward Ag+ ion under aqueous condition in the form ...of gel–sol transformation. The mechanism of such transformation was also investigated through UV–vis spectroscopy and powder X-ray diffraction.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Motivated by the demand for high-performance soft materials for applications in catalysis, drug delivery and biomedical materials, the development of smart hydrogels that possess both ...biocompatibility and stimulus responsiveness has been highly desirable. Here, we demonstrated a facile method to construct a multi-responsive supramolecular hydrogel by the formation of host–guest complexes between the tadpole-shaped PEG-POSS-(CD) 7 polymer and Azo-SS-Azo dimer. Incorporation of rigid POSS units furnished supramolecular cross-linked networks with high mechanical strength. The reversible gel–sol phase transition of supramolecular hydrogels could be induced by temperature, light and redox while the Azo derivatives could induce a quick gel–sol transition. These novel supramolecular hydrogels also possessed a favorable self-healing ability and better biocompatibility, which endowed the smart hydrogels with potential practical and real-life applications that will be beneficial for further development of more intelligent materials with desired functionalities.
