Acrylamide Research Articles

Lignin hydrogel sensor with anti-dehydration, anti-freezing, and reproducible adhesion prepared based on the room-temperature induction of zinc chloride-lignin redox system

In recent years, flexible sensors constructed mainly from hydrogels have received increasing attention. However, conventional hydrogels need to be prepared by high-temperature or radiation-induced polymerization reactions, which limits their practical applications due to their suboptimal electrical conductivity and weak mechanical properties. In this paper, using sodium lignosulfonate as the raw material, a dynamic catechol-quinone redox system formed by lignin‑zinc ions was constructed to initiate rapid free radical polymerization of acrylamide (AM) monomer at room temperature. In addition, Deep eutectic solvent (DES) can form a strong hydrogen bonding network within the molecules and between the molecules of the hydrogel, resulting in a hydrogel with good tensile properties (hydrogel elongation at break of 727.19 %, breaking strength of 84.09 kPa), and provides the hydrogel with high electrical conductivity, anti-dehydration, anti-freezing, and anti-bacterial properties. Meanwhile, the addition of lignin also improved the adhesion and UV resistance of the hydrogel. This hydrogel assembled into a flexible sensor can sense various small and large amplitude movements such as nodding, smiling, frowning, etc., and has a wide range of applications in flexible sensors.

Application of Coffee Silverskin Cellulose/Polyacrylamide Gel Polymer Electrolytes for Rechargeable Zinc-Ion Batteries

Rechargeable zinc-ion batteries (ZIBs) have grown in popularity due to their low cost and the abundance of resources. However, there has been little research into the development of gel polymer electrolytes (GPEs) for high voltage and capacity ZIBs. The use of agricultural waste as a polymer electrolyte (PE) is gradually increasing in order to support a circular economy. This study focuses on the utilization of cellulose derived from coffee silverskin (CS); coffee silverskin is a by-product generated during coffee roasting. We employ a reasonable approach to create the coffee silverskin cellulose (CSC)/polyacrylamide (PAM) GPE, with the goal of achieving good properties and improved battery performance. An investigation was conducted to determine the effect of CSC content in GPEs on ZIB characteristics. The cellulose derived from CS had a crystallinity index (CrI) of 64.60%. The optimal amount of cellulose added to the acrylamide monomer (AM) for the GPE of ZIB was found to be 2.5 mg (CSC/AM/salt weight ratio of 0.01/6/23). This amount resulted in the highest electrochemical stability and a cycling time of approximately 226 h. Furthermore, the PAM/Cellulose 2.5-based GPE exhibited increased Young’s modulus and tensile strength compared to the pure PAM. The electrochemical impedance spectroscopy (EIS) test revealed a diffusion resistance of 27.47 Ω and an ionic conductivity of 9.10 mS/cm at a temperature of 25 °C. Additionally, the use of cellulose in GPEs does not affect the electrochemical window. When the pure PAM-based GPE was compared to the CSC/PAM-based GPE, the biocomposites demonstrated electrochemical stability for a cycle life of over 200 cycles in the ZIB application.

Stretchable, Self-Healing, and Bioactive Hydrogel with High-Functionality N,N'-bis(acryloyl)cystamine Dynamically Bonded Ag@polydopamine Crosslinkers for Wearable Sensors.

Hydrogels present attractive opportunities as flexible sensors due to their soft nature and tunable physicochemical properties. Despite significant advances, practical application of hydrogel-based sensor is limited by the lack of general routes to fabricate materials with combination of mechanical, conductive, and biological properties. Here, a multi-functional hydrogel sensor is reported by in situ polymerizing of acrylamide (AM) with N,N'-bis(acryloyl)cystamine (BA) dynamic crosslinked silver-modified polydopamine (PDA) nanoparticles, namely PAM/BA-Ag@PDA. Compared with traditional polyacrylamide (PAM) hydrogel, the BA-Ag@PDA nanoparticles provide both high-functionality crosslinks and multiple interactions within PAM networks, thereby endowing the optimized PAM/BA-Ag@PDA hydrogel with significantly enhanced tensile/compressive strength (349.80kPa at 383.57% tensile strain, 263.08kPa at 90% compressive strain), lower hysteresis (5.2%), improved conductivity (2.51 S m-1) and excellent near-infrared (NIR) light-triggered self-healing ability. As a strain sensor, the PAM/BA-Ag@PDAhydrogel shows a good sensitivity (gauge factor of 1.86), rapid response time (138ms), and high stability. Owing to abundant reactive groups in PDA, the PAM/BA-Ag@PDA hydrogel exhibits inherent tissue adhesiveness and antioxidant, along with a synergistic antibacterial effect by PDA and Ag. Toward practical applications, the PAM/BA-Ag@PDA hydrogel can conformally adhere to skin and monitor subtle activities and large-scale movements with excellent reliability, demonstrating its promising applications as wearable sensors for healthcare.

Preparation of sodium alginate grafted polyelectrolyte by adiabatic polymerization and study on its solution properties

In order to improve the salt resistance and shear resistance of partially hydrolyzed polyacrylamide-based oil displacement agents (they are all anionic polyelectrolytes), this paper proposes the preparation of branched low hydrophobic monomer content sodium alginate grafted hydrophobically modified partially hydrolyzed polyacrylamide P(AM-SA-MO8) using acrylamide (AM), sodium alginate (SA), and non-ionic hydrophobic monomer (MO8) as main raw materials through the method of adiabatic polymerization followed by hydrolysis. The polymerization conditions of P(AM-SA-MO8) were optimized, and the solution properties and oil displacement performance of P(AM-SA-MO8) and P(AM-MO8) (copolymer of AM and MO8) were compared. It was found that the viscosity, resistance to Ca2+/Mg2+, shear resistance, resistance factor (RF), residual resistance factor (RRF), and enhanced oil recovery performance of P(AM-SA-MO8) solution were better than those of P(AM-MO8). Especially in seawater, at 75 ℃, the viscosity of 1500 mg/L P(AM-SA-MO8) solution was 6.5 mpa.s, RF was 6.08, RRF was 2.28, and the enhanced oil recovery was 26.28 % with a injection rate of 4.9 ft/day.

Repurposing Anakinra for Alzheimer's Disease: The In Vitro and In Vivo Effects of Anakinra on LPS- and AC-Induced Neuroinflammation.

Alzheimer's disease is a significant global health issue, and studies suggest that neuroinflammation plays a vital role in the advancement of this disease. In this study, anakinra has been shown to display a time- and concentration-dependent antineuroinflammatory effect. In the in vitro studies, it diminished the gene expressions of tumor necrosis factor-alpha (TNF-α) and nitric oxide (NO) synthase 2 stimulated by lipopolysaccharide (LPS). Anakinra also reduced the LPS-induced production of NO and reactive oxygen species. Thus, the hypertrophic state of LPS-activated BV2 microglial cells was reversed by anakinra. Furthermore, acrylamide (ACR)-induced activation of nuclear transcription factor-κB, TNF-α, and interleukin-1β was downregulated, while cAMP response element binding protein and brain-derived neurotrophic factor expression levels were markedly enhanced in ACR-treated zebrafish larvae. It was also observed that anakinra improved the uncoordinated swimming behaviors in ACR-exposed zebrafish larvae. Overall, anakinra demonstrated potential antineuroinflammatory and antioxidative effects.

Advancing DBD Plasma Chemistry: Insights into Reactive Nitrogen Species such as NO2, N2O5, and N2O Optimization and Species Reactivity through Experiments and MD Simulations.

This study aims to fine-tune the plasma composition with a particular emphasis on reactive nitrogen species (RNS) including nitrogen dioxide (NO2), dinitrogen pentoxide (N2O5), and nitrous oxide (N2O), produced by a self-constructed cylindrical dielectric barrier discharge (CDBD). We demonstrated the effective manipulation of the plasma chemical profile by optimizing electrical properties, including the applied voltage and frequency, and by adjusting the nitrogen and oxygen ratios in the gas mixture. Additionally, quantification of these active species was achieved using Fourier transform infrared spectroscopy. The study further extends to exploring the aerosol polymerization of acrylamide (AM) into polyacrylamide (PAM), serving as a model reaction to evaluate the reactivity of different plasma-generated species, highlighting the significant role of NO2 in achieving high polymerization yields. Complementing our experimental data, molecular dynamics (MD) simulations, based on the ReaxFF reactive force field potential, explored the interactions between reactive oxygen species, specifically hydroxyl radicals (OH) and hydrogen peroxide (H2O2), with water molecules. Understanding these interactions, combined with the optimization of plasma chemistry, is crucial for enhancing the effectiveness of DBD plasma in environmental applications like air purification and water treatment.

Synthesis and evaluation of a novel ternary quaternary ammonium salts-fluorescent template copolymer: Integrating flocculation, sterilization, and monitoring functions

Developing flocculants with sterilization and monitoring functions is of practical significance for optimizing water treatment agents. In this research, a fluorescent monomer, EtFl, with double bonds was synthesized and copolymerized with acrylamide (AM) and 3-(methacryloyloxy)propyltrimethylammonium chloride (MAPTAC) using a linear anionic template agent. This synthesis successfully produced a multifunctional template copolymer, TP(AM-MAP-EtFl), with flocculation, sterilization and monitoring capabilities. The fluorescence intensity of TP(AM-MAP-EtFl) was measured using a fluorescence spectrophotometer, demonstrating strong performance even with an EtFl monomer mass fraction as low as 0.5 wt‰, resulting in a fluorescence intensity value of 1000 a.u., suitable for analytical detection. In flocculation experiments with simulated wastewater containing E. coli, the introduction of the fluorescent monomer did not affect E. coli flocculation. When flocculation conditions are optimized, the OD600 readings of the clear liquid remaining after treating with TP(AM-MAP-EtFl#0.5) and TP(AM-MAP-EtFl#5) are 0.0297 and 0.0457, respectively, illustrating superior sterilization effects. Interestingly, SEM and 3D-EEM results confirmed TP(AM-MAP-EtFl)’s bactericidal effect on E. coli, with the introduction of the fluorescent monomer not affecting the sterilization capability of quaternary ammonium. This work integrates flocculation, sterilization and fluorescence properties to provide sterilization-type flocculants with monitoring capabilities, enabling accurate calculation of polymer concentration by detecting solution fluorescence intensity, thereby offering potential for online detection and automatic control of water treatment systems, demonstrating good applicability.

Baby Foods: 9 Out of 62 Exceed the Reference Limits for Acrylamide.

Acrylamide (AA) is a contaminant resulting from the Maillard reaction and classified by the International Agency for Research on Cancer (IARC) as a probable carcinogen in Group 2A, with proven neurotoxic effects on humans. European Union (EU) Regulation No. 2017/2158 is currently in force, which establishes measures meant to reduce AA levels in food and sets reference values, but not legal limits, equal to 40 and 150 μg/kg AA in processed cereal-based foods intended for infants and young children and in biscuits and rusks, respectively. For this reason, sixty-two baby foods were analyzed using ultra-high performance liquid chromatography with diode array detector and quadrupole time-of-flight mass spectrometry (UHPLC-DAD-Q-TOF/MS) to check whether industries were complying with these values, even though AA control is not legally mandatory. In total, 14.5% of the samples exceeded the reference values; these were homogenized chicken products (211.84 ± 16.53, 154.32 ± 12.71, 194.88 ± 7.40 μg/kg), three biscuits (276.36 ± 0.03, 242.06 ± 0.78, 234.78 ± 4.53 μg/kg), a wheat semolina (46.07 ± 0.23 μg/kg), a homogenized product with plaice and potatoes (45.52 ± 0.28 μg/kg), and a children's snack with milk and cocoa (40.95 ± 0.32 μg/kg). Subsequently, the daily intake of AA was estimated, considering the worst-case scenario, as provided by the consumption of homogenized chicken products and biscuits. The results are associated with margins of exposure (MOEs) that are not concerning for neurotoxic effects but are alarming for the probable carcinogenic effects of AA.

Design of hybrid multi-crosslinked hydrogel with a combination of high stiffness, elastic applied in high temperature and high salinity reservoirs

The mechanical strength of conventional hydrogels is inadequate for preventing leakage in high-temperature and high-salinity reservoirs, primarily due to the increased mobility of polymer chains and the degradation of crosslinked networks. Herein, we employed the strategy of ’network nesting and layer reinforcement’ to design a hybrid multi-site crosslinked hydrogel. This approach enhances the interconnections between polymer chains and fortifies the crosslinked network. The shear rheological behavior and temperature sensitive characteristics of the profile control working fluids were evaluated based on rheological dynamics. In the high temperature (140 ℃) and high salinity (21.81 × 104 mg/L) preparation environment, the effects of different components to the mechanical strength of the hydrogel were investigated under dynamic shear and uniaxial compression conditions. The incorporation of N-(hydroxymethyl)acrylamide (NMA) in the copolymerization with acrylamide (AM) resulted in an increase in the covalent cross-linking density, leading to a rise in the shear elastic modulus from 105 Pa to 238 Pa. The use of pre-gelatinized cassava starch (PGCM) as the grafting framework enhanced the bonding between the polymer chains, as evidenced by the increase in uniaxial compressive strength from 0.018 MPa to 0.081 MPa and the rise in peak strain from 55.0 % to 72.9 %. Furthermore, the synergistic effect of fumed silica (AEROSIL), which exploits mechanical coupling between inorganic nano-fillers and organic polymers, increased the compressive strength from 0.081 MPa to 0.418 MPa and raised the peak strain from 72.9 % to 81.8 %. It provides an effective approach to enhance the plugging performance of hydrogels in high temperature and high salinity reservoirs.

Reduction of eEF2 kinase alleviates the learning and memory impairment caused by acrylamide

BackgroundThe impact of acrylamide (ACR) on learning and memory has garnered considerable attention. However, the targets and mechanisms are still unclear.ResultsElongation factor 2 (eEF2) was significantly upregulated in the results of serum proteomics. Results from in vitro and in vivo experiments indicated a notable upregulation of Eukaryotic elongation factor 2 kinase (eEF2K), the sole kinase responsible for eEF2 phosphorylation, following exposure to ACR (P < 0.05). Subsequent in vitro experiments using eEF2K siRNA and in vivo experiments with eEF2K-knockout mice demonstrated significant improvements in abnormal indicators related to ACR-induced learning and memory deficits (P < 0.05). Proteomic analysis of the hippocampus revealed Lpcat1 as a crucial downstream protein regulated by eEF2K. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses indicated that eEF2K may play a role in the process of ACR-induced learning and memory impairment by affecting ether lipid metabolism.ConclusionsIn summary, eEF2K as a pivotal treatment target in the mechanisms underlying ACR-induced learning and memory impairment, and studies have shown that it provides robust evidence for potential clinical interventions targeting ACR-induced impairments.

Removal of copper and cobalt ions from aqueous solutions using starch‐xanthate based novel smart hydrogel via adsorption technique: Swelling, adsorption isotherm, and kinetic study

AbstractThe concentration of harmful metal ions is growing globally, which raises the risk to both human and ecological health. The use of “adsorption” technique has been found to be very effective, for the removal of toxic metal ions. Among other things, hydrogels as an adsorbent work effectively for the removal of toxic metal ions and other aquatic pollutants. The newly designed potato starch‐xanthate (SX) based hydrogel (SX‐modified hydrogel) has been synthesized using a mixture of acrylamide (AAm) and acrylic acid (AA) monomers, with the help of free‐radical graft copolymerization technique. The synthesized SX‐modified hydrogel has been characterized by several analytical techniques, namely, UV–visible (UV–vis) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, gel permeation chromatography (GPC), thermogravimetric (TG) analysis, point of zero charge (ΔpHPZC) analysis, x‐ray diffraction (XRD) analysis, and scanning electron microscope (SEM) analysis. The main objective of the current work is to remove the Cu2+ and Co2+ ions from wastewater using SX‐modified hydrogel as well as to study the swelling and water retention properties of the SX‐modified hydrogel. The swelling ratio of SX‐modified hydrogel has been found to be 312.31, 374.01, and 410.20 g/g at optimum pH 10, temperature 35°C, time 675 min in gray wastewater, tap water, and distilled water, respectively. The maximum percentage removal of Cu2+ and Co2+ ions by SX‐modified hydrogel has been found as 97.7% and 94.2%, respectively, at optimum conditions. The Langmuir isotherm model fits best with the experimental data, with maximum adsorption capacity of 515.46 mg/g for Cu2+ and 483.09 mg/g for Co2+ ions, respectively. The kinetic studies suggest that the adsorption process is governed by the second order kinetic model with rate constant of 2.06 × 10−4 g/(mg min) for Cu2+ and 1.79 × 10−4 g/(mg min) for Co2+ ions, respectively. The negative ΔG values suggest the adsorption process is spontaneous in nature. In addition, the positive ΔH values support the adsorption process is endothermic in nature. The SX‐modified hydrogel showed a remarkable desorption efficiency with 96.7% for Cu2+ and 92.5% for Co2+ ions and reusability for four consecutive adsorption–desorption cycles. It can be concluded that the SX‐modified hydrogel has showed an effective, economical, easy, low energy consuming, and significant potential in the treatment of wastewater containing heavy metal ions.

Preparation and Performance Evaluation of a Supramolecular Polymer Gel-Based Temporary Plugging Agent for Heavy Oil Reservoir.

When encountering heavy oil reservoirs during drilling, due to the change in pressure difference inside the well, heavy oil will invade the drilling fluid, and drilling fluid will spill into the reservoir along the formation fractures, affecting the drilling process. A supramolecular polymer gel-based temporary plugging agent was prepared using acrylamide (AM), butyl acrylate (BA), and styrene (ST) as reacting monomers, N, N-methylenebisacrylamide (MBA) as a crosslinking agent, ammonium persulfate (APS) as an initiator, and poly(vinyl alcohol) (PVA) as a non-covalent component. A supermolecular polymer gel with a temperature tolerance of 120 °C and acid solubility of 90% was developed. The experimental results demonstrated that a mechanically robust, thermally stable supramolecular polymer gel was successfully synthesized through the copolymerization of AM, BA, and ST, as well as the in situ formation hydrogen bonding between poly (AM-co-BA-co-ST) and PVA, leading to a three-dimensional entangled structure. The gel-forming solution possessed excellent gelling performance even in the presence of a high content of salt and heavy oil, demonstrating superior resistance to salt and heavy oil under harsh reservoir conditions. High-temperature and high-pressure plugging displacement experiments proved that the supramolecular polymer gel exhibited high pressure-bearing capacity, and the blocking strength reached 5.96 MPa in a wedge-shaped fracture with a length of 30 cm. Furthermore, the dissolution rate of the supramolecular polymer gel was as high as 96.2% at 120 °C for 48 h under a 15% HCl solution condition.

Modulating Solvation Shell with Acrylamide Electrolyte Additives for Reversible Zn Anodes.

The reconsideration of aqueous zinc-ion batteries (ZIBs) has been motivated by the attractive zinc metal, which stands out for its high theoretical capacity and cost efficiency. Nonetheless, detrimental side reactions triggered by the remarkable reactivity of H2O molecules and rampant dendrite growth significantly compromise the stability of the zinc metal anode. Herein, a novel approach was proposed by leveraging the unique properties of acrylamide (AM) molecules to increase the driving force for nucleation and parasitic reactions. Combined with experimental data and theoretical simulations, it is demonstrated that the incorporation of AM additive can reconstruct the solvation shell around Zn2+ and reduce the number of active H2O molecules, thereby effectively reducing the H2O molecule decomposition. Consequently, the Zn//Zn symmetric batteries with AM-containing ZnSO4 electrolytes can attain excellent long-term performances over 2000 h at 1 mA cm-2 and nearly 500 h at 10 mA cm-2. The Zn//VO2 full batteries still display improved cycling performances and a high initial discharging capacity of 227 mA h g-1 at 3 A g-1 compared to the ZnSO4 electrolyte. This electrolyte optimization strategy offers new insights for achieving long-term ZIBs and advances the progress of ZIBs in energy storage.

Synthesis and properties of AM/AMPS/MMA and cationic monomer copolymer flooding agent

Abstract A novel hydrophobic association copolymer (PAMA) was synthesized by incorporating acrylamide (AM), 2-acrylamide-2-methylpropanesulfonic acid (AMPS), cationic monomer (MEDDA), and methyl methacrylate (MMA). The properties of MMA copolymers with varying contents were analyzed using infrared spectroscopy, nuclear magnetic resonance spectroscopy, and scanning electron microscopy. Optimal overall performance of the solution was achieved when the MMA content reached 1.4 % w/w. Compared to pure PAAM (without MMA), the PAMA-1.4 % polymer exhibited superior viscoelasticity, temperature resistance, and shear resistance. This enhancement in PAMA performance can be attributed to the significant inhibition of intermolecular water film formation within the polymer matrix by MMA, effectively improving and regulating solution solubility while strengthening molecular chain interactions and enhancing the structural network strength of PAMA polymers. Additionally, the inclusion of MMA transformed rock surfaces from non-wetting to wetting conditions, thereby greatly improving oil displacement efficiency. In displacement experiments, PAMA-1.4 % performed better in terms of enhanced oil recovery, the recovery rate of 0.1 % w/w PAMA-2.4 % solution is only 7.78 %, while the recovery rate of 0.1 % w/w PAMA-1.4 % solution is 13.06 %.

Evaluation of the synergistic effect of nanocomposite hydrogel based on imidazolium nitrate ionic liquids for enhanced oil recovery

A comprehensive research study was conducted to examine the synergistic properties of ionic liquids, and hydrogels. Two nanocomposite hydrogel samples were created: one with ionic liquid and the other without. The samples were made using hydrogel with acrylamide (AM) backbone, Al2O3 nanoparticles, and ionic liquid [C8mim][NO3]. The effectiveness of a nanocomposite hydrogel containing an ionic liquid was tested to improve the wettability alteration and sweeping efficiency of reservoirs. Various tests were performed including IFT, electroconductivity, micromodel, SEM, and equilibrium swelling tests. The tests showed that the presence of the ionic liquid increased the swelling up to 102 %. IL increased conductivity by 124.24 % and 44.86 % at ambient temperature and 90 °C respectively. In the strain sweep test, the maximum elastic modulus for NCH-IL was recorded as 40,350 Pa, while for the sample without ionic liquid, it was 27,100 Pa. The frequency sweep test confirmed the three-dimensional structure of the gel. IL increased the maximum elastic modulus from 13,200 Pa to 27,400 Pa. The critical frequency value also increased by 87.5 %. Moreover, the suspension, which contains 1 wt% of Nanocomposite Hydrogel based on Imidazolium Nitrate Ionic Liquids, has shear-thinning properties, making it easy to inject into reservoirs. The reduction of the contact angle from 109° to 14.2° demonstrated the ability of IL to alter the wettability of NCHs. This result stemmed from the release of part of the ionic liquid within the hydrogel structure, as confirmed by the UV test. During the emulsion stability test, it was observed that the NCH-IL sample created a stable emulsion and a more complete two-phase separation than the sample without the ionic liquid. The sample that contained IL recorded 85 % and 78.4 % oil recovery in homogeneous and heterogeneous micromodels, respectively. Whereas, the sample without IL recorded 71.27 % and 60.73 % in the same micromodels.

Enhancing cement-based composites via regulated hydration and concurrent construction of robust organic-inorganic network

Cement-based materials with excellent mechanical properties are in high demand in the civil engineering. This work utilized an innovative in-situ copolymerization approach for synergistic modification of cement-based materials. Vinyl hybrid silica microspheres (VSM) were synthesized through the sol-gel method. Subsequently, With the assistance of initiators and cross-linking agents, the VSM and acrylamide (AM) in-situ copolymerization and were uniformly dispersed in the cement matrix, leading to the successful development of a modified cement-based material. The copolymerization of VSM and AM resulted in the creation of a comprehensive three-dimensional hybrid network structure, interconnected by covalent bonds between the constituent components. Experimental results unequivocally demonstrate that the mechanical properties of the composite have undergone remarkable enhancement. Notably, the flexural strength experienced a substantial increase due to the in-situ polymerization of AM. Furthermore, the compressive strength was significantly improved, achieving a 21.4 % increase compared to samples modified with 2 wt% AM alone. The enhancement can be attributed to the synergistic effect of the in-situ copolymerization structure and the VSM attached to it. The microspheres not only aided in the development of a robust cement matrix and a higher compactness, but also bolstered the compressive modulus of the flexible polymer chains. Collectively, these factors contributed to an increase in the overall resistance to deformation, comprehensively enhancing the mechanical performance of the material. This study addresses the challenges posed by the loss of compressive strength during in-situ polymerization modification, introduces an innovative methodology aimed at significantly enhancing the mechanical properties of cement-based materials.

Multifunctional and immunoregulatory microenvironment-responsive hydrogel for whole course management of infected diabetic wounds

Infective diabetic wounds can significantly delay healing and pose severe infection risks. The process of infective diabetic wounds healing (DWH) are not only re-epithelialization and angiogenesis but also anti-bacterial, hair follicles regeneration and nerve growth. In this study, a stable dynamic hydrogel system was formulated by incorporating dynamic borate easter bond and carbon–carbon double bond, which based on tannic acid (TA) − acrylic phenyl boric acid (APBA) and acrylamide (AM). Subsequently, a hydrogel (ATAN-Met) was obtained by modifying the antibacterial ammonium cationic (N+) and loading metformin (Met). This system demonstrated impressive wet adhesion, self-healing, wearable and peelable properties, responding to glucose/reactive oxygen species (ROS) for drug release. In vitro and vivo experiments illustrated that ATAN-Met recruited mesenchymal stem cell (MSC), facilitating interaction between MSC and neural cells, regulating macrophage polarization, and modulating the diabetic wound microenvironment while exhibiting anti-bacterial property, ultimately leading to re-epithelialization and neurovascular-hair follicles regeneration. RNA and metabolomic sequencing indicated that ATAN-Met activate the Hippo pathway, inhibit the TNF pathway, and regulate wound metabolism to improve the diabetic wound microenvironment. These results suggest that the microenvironment-responsive ATAN-Met hydrogel shows considerable potential for the whole course management of infective DWH.

Fabrication of organogel strain sensor with self-healing property and extreme temperature tolerance by using phytic acid-liquid metal as initiator

Wearable strain sensors have aroused myriad of interest in the domain of electronic skin, soft robotics, and biomedicine. Organogels for wearable strain sensors require desirable stretchability, sensing stability, self-healing property, and a wide working temperature range. However, the synthesis of such organogels typically involves complex and time-consuming processes. Herein, we proposed a rapid copolymerization method for organogels composed of poly(acrylic acid-co-acrylic amide) (P(AA-co-AM)), phytic acid (PA), liquid metal (LM), and polyethylene oxide (PEO). The dispersion of GaInSn in PA solution (GaInSn-PA) was synthesized and employed to initiate the copolymerization of acrylic acid (AA) and acrylic amide (AM), which significantly reduced polymerization time to 2–3 min at room temperature. The release of Ga3+ ions from the LM facilitated cross-linking of P(AA-co-AM) chains through coordination bonds, while also imparted conductivity to the organogel. The synergistic effect between hydrogen bonds and metal coordination bonds extensive within the polymer chains imparted exceptional stretchability (1079 % strain) and self-healing efficiency (98 % at 60 °C) to the organogel. Consequently, the resulting strain sensor demonstrated the ability to accurately monitor both subtle and large human motion, exhibiting remarkable repeatability and durability across a wide temperature range (-20 °C∼40 °C). In addition, the integration of strain sensors on limbs for robotic control through limb movements underscored its practical viability. This optimized fabrication approach and structural design strategy set a new precedent for the development of organogel strain sensors in various applications.

Engineering PDA@CNTs-Enhanced sulfobetaine methacrylate hydrogels for superior flexible sensor applications

Conductive hydrogels have attracted significant attention as versatile materials for flexible sensors, with potential implementation in wearable technologies, electronic skins, and health diagnostics. However, traditional hydrogel models are frequently limited by their inadequate mechanical strength, poor conductivity, weak adhesion, and low durability, which pose significant barriers to their further application in flexible sensors. In this work, we prepared composite multifunctional hydrogels as flexible sensors, which were synthesized from sulfobetaine methacrylate SBMA) and acrylamide (AM), infused with dodecyl quaternary ammonium salt (Q12), and incorporated with poly(dopamine)-functionalized carbon nanotubes (PDA@CNTs). The PDA modification enhances the compatibility of CNTs with the hydrogel matrix. The incorporation of PDA@CNTs into the hydrogel matrix, along with the establishment of multiple dynamic bonds—such as ionic bonds, hydrogen bonds, cation-π interactions, and π-π stacking between polymer chains and PDA moieties—significantly enhances its tensile strength (53.79 kPa), toughness (134.77 kJ/m3), adhesive capabilities (29.84 kPa to paper), and electrical conductivity (0.2 S/m). Moreover, the composite hydrogel reveals a remarkable mechanical strain response, coupled with impressive stability and durability over prolonged periods. It efficiently differentiates between mild elongations (10%–40 %) and substantial elongations (50%–300 %), thereby showcasing its capability for real-time biomechanical motion monitoring. Additionally, the composite hydrogel displays remarkable photothermal antibacterial efficacy upon exposure to near-infrared (NIR) radiation, along with outstanding biocompatibility under standard conditions, thereby confirming its suitability for safe and long-term biological interactions. The exceptional functionality of these composite hydrogels renders them highly conducive to diverse applications in the realm of wearable sensor technologies.

Withdrawal: Conductive Hydrogel Dressing With High Mechanical Strength for Joint Wound Healing.

Hydrogel wound dressing can accelerate angiogenesis to achieve rapid wound healing, but traditional hydrogel dressings are difficult to meet the repair of joint sites due to their low mechanical strength. Therefore, we constructed the gel system by designing the chemical-physical interpenetrating network structure to achieve high strength and high toughness of the hydrogel. The high-strength double-network hydrogels were synthesized by simple free radical polymerization and low-temperature physicochemical cross-linking in our experiments. The suspension was obtained by green reduction of graphene oxide with carboxymethyl chitosan, followed by the introduction of acrylamide (AM) to form a covalent cross-linked network, which was immersed in ferric chloride solution to form metal ligand bonds, and finally the chemical-physical dual cross-linked network hydrogel wound dressing was prepared. Here, reduced graphene oxide can enhance electrical conductivity and excellent near-infrared photothermal effect to the hydrogel. The cell viability of this novel wound dressing was above 90.0%, its hemolysis rate was below 2.0%, and the electrical conductivity could reach (6.89 ± 0.07 (mS/cm)). In addition, the stress-strain curve demonstrated that the double cross-linked network hydrogel could reach a stress of more than 0.8MPa at 82.0% strain, and the cyclic compression experiment shows that it can still recover its original shape after five times of repeated compression. This work can provide a reference for the exploitation of high mechanical strength hydrogel wound dressings with good electrical conductivity and near-infrared photothermal effect. This article is protected by copyright. All rights reserved.