The construction of high-performance conductive hydrogels with extensibility, transparency, conductivity and responsiveness has been successfully applied in the field of flexible stretchable electronics. However, since water freezes at low temperatures, these hydrogels become brittle and hard, losing their original flexibility and elasticity, thereby limiting their applications in low-temperature environments. Meanwhile, the moist environment of hydrogels provides ideal conditions for bacterial proliferation, which not only compromises the service life of hydrogel sensors but may also pose potential health risks to users. Herein, an antibacterial and anti-freezing hydrogel (PPHG) was prepared by the freeze-thaw method using polyvinyl alcohol (PVA), hyaluronic acid (HA), polyhexamethylene biguanide (PHMB), glycerol (GL), and sodium chloride (NaCl). The prepared hydrogel effectively inhibits the growth of both Gram-negative and Gram-positive bacteria. At the same time, it has temperature resistance at -20 °C and can maintain high extensibility (>350% strain), conductivity, and responsiveness. Furthermore, this type of water-based gel with exceptional toughness and elasticity can construct and print complex three-dimensional structures. The high-performance sensors fabricated from it not only can accurately capture human movement, but also sensitively detect Morse code. Meanwhile, this sensor also possesses excellent fatigue resistance and rapid response capabilities, providing a solid theoretical and technical foundation for the development of the next generation of intelligent medical devices and their practical applications in the field of health monitoring.

In recent years, flexible strain sensors fabricated by using ultraviolet light-curing technologies have garnered significant attention for wearable devices and human motion monitoring. However, developing hydrophobic flexible sensors with good mechanical strength and environmental stability remains a great challenge. Herein, an ultraviolet-curable silane side-chain-modified polyurethane acrylate material was fabricated for flexible sensing applications. A hydroxyl-terminated silane coupling agent (APIP) was synthesized to modify polyurethane acrylate (PUA). The results indicate that the amount and structure of APIP affect the polymerization performance, thermodynamic properties, tensile properties, and hydrophobicity of PUA. When 20 wt % APIP was added, the sample (PUA-APIP/20%) exhibited a water contact angle of 104 degrees, which represents a significant increase from the 74 degrees of the original PUA. The tensile strength and elongation at break of PUA-APIP/20% increased to 8.67 MPa and 378.84%, respectively. The composite of PUA-APIP and lithium bis(trifluoromethane sulfonyl) imide (LiTFSI) could be instantly cured under UV irradiation to produce a flexible thin-film strain sensor. This composite strain sensor was used to detect large-amplitude human movements (such as finger, elbow, and knee flexion) as well as subtle muscle contractions and can yield stable strain responses. This work offers strategies for the development and sustainable production of wearable, flexible electronic devices.

Polyurethane (PU) exhibits significant application value, owing to its outstanding elasticity, structural tunability, and potential for functional integration. However, the preparation of traditional PU suffers from long curing time and short service life, while the poor dispersion of inorganic conductive fillers tends to reduce the flexibility of the polymer matrix. Herein, polyurethane acrylate modified with disulfide bonds and double bond-terminated structures (PUSA) was synthesized via a solvent-free fabrication method. The material exhibits excellent mechanical properties, with a tensile strength of up to 9.7 MPa and a tensile strain of up to 310%. The incorporation of LiTFSI optimizes the ionic transport channels between the ionic liquid and PUSA, significantly enhancing the electrical conductivity of the material. The resulting sensor exhibits excellent mechanical and electrical properties, along with high repeatability and favorable hydrophobic retention during cyclic deformation. Furthermore, inspired by the high hydrophobic characteristics of duck feathers, the as-prepared film was engineered with biomimetic asymmetric barb microstructures, exhibiting outstanding hydrophobicity and moisture barrier performance, with a static water contact angle (WCA) of up to 147.88 degrees. This investigation provides a promising pathway for the design and creation of flexible sensors in the fields of health monitoring and human-computer interaction.

Hydrogel electrolytes, combining the ionic conductivity of liquid electrolytes and the mechanical properties of solids, are promising for flexible, safe, and cost-effective zinc-ion hybrid supercapacitors (ZIHC). However, the hydrogel electrolyte contains a large number of free water molecules, resulting in a limited electrochemical window and inevitable side reactions on the anode side, which are not conducive to the electrical output performance and long-term stable operation of the device. In this study, a polyionic hydrogel electrolyte was synthesized from quaternary ammonium chitosan, acrylamide, sodium acrylate, and sodium allyl sulfonate. The coordination between Zn2 + and carboxyl groups endowed the electrolyte with self-healing capability and mechanical strength (breaking stress: 141.5 kPa). Sulfonate groups reduced the desolvation energy barrier of hydrated Zn2+ and promoted Zn2+ diffusion, while ethylene glycol suppressed water activity via hydrogen bonding, thus inhibiting anode side reactions and improving low-temperature tolerance. The resulting ZIHC achieved a wide voltage window of 2.2 V and delivered a specific capacity of 282.75 mAh g−1 at 0.5 A g−1. It maintained 88.9% capacity after 15,000 cycles, with suppressed zinc dendrite growth. Moreover, the device demonstrated outstanding flexibility, safety, and environmental adaptability, functioning reliably under bending or cutting.

As a hydrophilic polymer material with unique physicochemical properties and biomimetic characteristics, hydrogel has attracted wide attention in the fields of chemistry, materials science, biomedicine, and engineering. However, hydrogel sensors produce bacteria during repeated use, increasing the risk of skin infections and decreasing the lifespan of hydrogel sensors. Thus, a conductive antimicrobial hydrogel sensor based on a xanthan gum-polyvinyl alcohol dual network structure was produced using freeze-thaw method. Polyhexamethylene biguanide was introduced to endow the hydrogel with significant antibacterial activity, showing inhibition zone diameters of 2.1 +/- 0.2 mm and 3.3 +/- 0.1 mm against Escherichia coli and Bacillus subtilis, respectively, along with excellent antibacterial stability. Meanwhile, the hydrogel possesses excellent toughness and elasticity with a maximum fracture strength of 327 kPa and a strain at break of 375%, and it can be molded into various three-dimensional shapes. In addition, hydrogels can monitor the movements of various joints in the human body in real time and also detect weak electromyography signals with a high sensitivity factor of 3.37 and millisecond-level response/recovery speed. Therefore, the biocompatibility and sensitivity of hydrogels provide a new material basis for wearable sensors and artificial skin diagnostics.

The electrospinning nanofiber membranes modified by nanoparticles can effectively improve anti-oil adhesion and separation performance. However, the low stability of nanoparticles on the fiber membrane surface substantially limits the operational lifespan of the membrane. Herein, poly(vinylidene fluoride) (PVDF) nanofiber membranes with multi-scale microporous channel structures are prepared using coaxial electrospinning and a sacrificial template strategy. Subsequently, iron phytate nanoparticles are grown in situ on the fibers to fill the porous structures by utilizing the hollow and porous nanofibers as a framework. The interlocking structure between the nanoparticles and the porous fibers significantly enhances the stability and durability between nanoparticles and the fiber membrane. Even after being subjected to ultrasonic treatment for 7 h, there is no discernible shedding of nanoparticles from the fiber membrane. The prepared nanofiber membrane demonstrates exceptional superhydrophilicity and underwater superoleophobicity, exhibiting remarkable self-cleaning capability and resistance to crude oil contamination. Additionally, the membrane efficiently separates various oil-in- water emulsions, achieving a high separation efficiency of over 99%. Moreover, the membrane also demonstrates excellent adsorption capability towards cationic dyes. Therefore, this interlocking structure composed of nanoparticles and nanofibers presents new ideas and insights for the preparation of high-performance and durable oil-water separation membranes.

Hydrogels served as core materials for wearable sensors in recent years, yet their practical application was constrained by water-loss-induced instability, suboptimal mechanical properties, and insufficient functionality in complex scenarios. To overcome these challenges, this study innovatively engineered a Janus fiber scaffold-based composite hydrogel biomimetic skin with a triple humidity-responsive mechanism, achieving substantial breakthroughs in performance optimization and multifunctional integration. HSBS leveraged triple humidity response mechanisms: chitosan-gelatin buffering, Janus scaffolds' unidirectional conduction, and LiCl deliquescence, achieving high hygroscopic sensitivity across 30-90 % RH. Concurrently, the HSBS exhibited wide temperature adaptability from -20 degrees C to 50 degrees C, exceptional strain-sensing stability, and mechanical durability, with a water retention rate of 76 % at room temperature and a tensile strength of 3.09 MPa. It could also precisely detect variations in skin temperature and humidity, as well as fluctuations in physiological signals. Endowed with a triple humidity-responsive mechanism as its core advantage, this novel biomimetic skin was poised to significantly expand the application frontier of wearable sensors in domains such as healthcare monitoring and sports science.

As a new flexible electronic device, hydrogel sensors express unique value in biomedical, wearable, and smart medical fields. However, hydrogel sensors achieve high sensitivity while supporting bacterial growth, increasing the risk of human infection and shortening the service life of hydrogel sensors. Thus, a conductive antibacterial hydrogel sensor based on polyvinyl alcohol-sodium alginate dual network structure was designed and prepared by freeze-thaw method. The polyhexamethylene-biguanide was introduced into hydrogel with excellent antibacterial effect and antibacterial stability of 7 days for Gram-positive and Gram-negative bacteria. Meanwhile, the remarkable fracture strain (325%) and stress (226 kPa) of hydrogels can create complex three-dimensional structures as well as achieve 3D print effects. Moreover, the hydrogel can not only monitor human movement in real time (such as finger bending, vocalization, etc.), but also detect weak electromyographic signal. Therefore, the antibacterial property, fatigue resistance, and fast response of hydrogel sensor provide a theoretical basis for human health monitoring and the development of the next generation of intelligent medical devices.

Adhesives have received extensive attention in flexible bioelectronics, wearable electronic medical devices, and biofuel cells. However, it is a challenge to achieve late regulation of performance once polymer-based gels are formed. Here, a double-network organogel composed of a hydrophilic and hydrophobic polymer network and a polyamide acid network was successfully prepared. In diverse liquid environments (including isopropyl alcohol, glycerol, epichlorohydrin, n-propanol, dichloromethane, triethanolamine, ethanol absolute, hydrogen peroxide, and ethyl acetate), the organogel adhesive demonstrated remarkable properties. It exhibits a strong tensile strength of 200 kPa, a high fracture strain reaching 560%, and an impressive adhesion strength of 38 kPa. In addition, the organogel demonstrates exceptional adhesive properties toward polytetrafluoroethylene, plastics, metals, rubber, and glass. Note that the organogel could also regulate adhesive and tough performance by thermally triggering a cyclization reaction even after the organogel has been formed. The strategy provides a new idea for designing soft materials with post-tunability.

Aqueous zinc-ion hybrid supercapacitors (ZIHC) have been widely researched due to their inherent high safety, low cost, and high power. However, the low operating voltage of aqueous electrolytes, H2O-induced side reactions, and intractable dendrites severely compromise the energy output and durability of ZIHC. Herein, a freeze-tolerant zwitterionic organic hydrogel electrolyte (PSAMOHE) was constructed for high-voltage flexible ZIHC. The hydrogen bonding between ethylene glycol and water inhibited the formation of ice crystals, preventing the electrolyte from freezing at -40 degrees C. Concurrently, the hydrophilic PSAMOHE mitigated harmful side reactions and achieved a wide electrochemical stability window (2.2 V) by anchoring water molecules. In addition to exhibiting exceptional interface adhesion and mechanical adaptability, PSAMOHE with charged functional groups effectively facilitated ion migration, diminished the desolvation energy barrier of hydrated Zn2+, and induced uniform Zn deposition. By combining these advantages, the assembled flexible ZIHC exhibited a battery-level specific capacity of 269.1 mAh/g (at 0.5 A/g), impressive environmental adaptability, and excellent mechanical adaptability. Impressively, the ZIHC maintained 89.5 % of the initial capacity and obtained a dendrite-free Zn anode after 14,000 cycles of charge and discharge. This study provides valuable insights into the exploration of hydrogel electrolyte engineering for high-performance zinc-based flexible energy storage devices.

In supramolecular materials, multiple weak binding groups can act as a single collective unit when confined to a localized volume, thereby producing strong but dynamic bonds between material building blocks. This principle of multivalency provides a versatile means of controlling material assembly, as both the number and the type of supramolecular moieties become design handles to modulate the strength of intermolecular interactions. However, in materials with building blocks significantly larger than individual supramolecular moieties (e.g., polymer or nanoparticle scaffolds), the degree of multivalency is difficult to predict or control, as sufficiently large scaffolds inherently preclude separated supramolecular moieties from interacting. Because molecular models commonly used to examine supramolecular interactions are intrinsically unable to examine any trends or emergent behaviors that arise due to nanoscale scaffold geometry, our understanding of the thermodynamics of these massively multivalent systems remains limited. Here we address this challenge via the coassembly of polymer-grafted nanoparticles and multivalent polymers, systematically examining how multivalent scaffold size, shape, and spacing affect their collective thermodynamics. Investigating the interplay of polymer structure and supramolecular group stoichiometry reveals complicated but rationally describable trends that demonstrate how the supramolecular scaffold design can modulate the strength of multivalent interactions. This approach to self-assembled supramolecular materials thus allows for the manipulation of polymer-nanoparticle composites with controlled thermal stability, nanoparticle organization, and tailored meso- to microscopic structures. The sophisticated control of multivalent thermodynamics through precise modulation of the nanoscale scaffold geometry represents a significant advance in the ability to rationally design complex hierarchically structured materials via self-assembly.

Hydrogel-based zinc ion hybrid supercapacitors (ZIHS) have stood out from many energy storage device candidates due to their battery-level energy density, inherent flexibility, and safety. Nevertheless, the inevitable dendrite growth of Zn anodes and sharp capacity degradation at low-temperature seriously hinder their practical application. Herein, a dense ZnF2 solid electrolyte interface protective layer was constructed in situ on the Zn electrode surface by a simple chemical deposition method, effectively isolating the water molecules and alleviating the water-induced dendrite growth and parasitic reaction. To achieve the flexible ZIHS with environmental adaptability, a self-adhesion and anti-freezing zwitterionic hydrogel electrolyte was fabricated to afford superior ionic conductivity (97.1 mS cm -1), excellent anti-drying ability, and robust interfacial adhesion. Benefitting from the integrated merits of the as-designed electrolyte and electrode, the ZIHS delivered excellent mechanical adaptability, favorable energy density (103.9 Wh kg- 1 at 270.1 W kg -1), broad operating temperature range (-40 to 40 degrees C), along with long-term cycling stability (12,000 cycles) with 90.3 % capacity retention at-25 degrees C. Notably, the unencapsulated ZIHS achieved exceptional electrochemical stability in an open environment. This finding provides valuable insights for constructing durable, flexible, and environmentally adaptable zinc-based energy storage systems.

Bubble-free bilayer graphene has been fabricated by directly dry-laminating the clean backsides of two single graphene layers with designed asymmetric transfer media.

With the widespread application of portable electronic devices, high-performance supercapacitors have attracted enormous interest. Nevertheless, the previously reported supercapacitors typically suffer from a few disadvantages, such as the low energy density, irreversible breakage and poor interface combination between electrolyte and electrodes, restricting the development of high-performance supercapacitors. Herein, the betaine-based zwitterionic hydrogel electrolyte with excellent self-healing properties, anti-drying ability and mechanical flexibility was prepared for zinc-ion hybrid supercapacitor (ZIHS). Betaine enhanced the adhesion of zwitterionic hydrogel electrolytes, which promoted the interface bonding between electrolyte and electrode. Impressively, the ZIHS based on zwitterionic hydrogel electrolytes exhibited a wide electrochemical stability window of 2.2 V and a high energy density of 237.34 mAh/g. In addition, the ZIHS based on zwitterionic hydrogels possessed great self-healing ability, the self-healing efficiency achieved 88.3 % of the initial state after five cutting-healing cycles. This research will supply an effective strategy for the design of hydrogel-based supercapacitors with wide voltage windows, high energy density and reusability.

Conductive, stretchable, and flexible hydrogel wearable sensors have attracted extensive attention in the fields of artificial intelligence and electronic equipment. However, it is an enormous challenge to fabricate conductive hydrogel sensors with biocompatibility, antibacterial properties, and toughness. Here, a highly conductive hydrogel with excellent toughness, good biocompatibility, and strong antibacterial properties was prepared by incorporating acetylated distarch phosphate (ADSP) into poly(vinyl alcohol) (PVA)/polyhexamethylene biguanide hydrochloride (PHMG). The addition of ADSP not only ionized sodium ions to make the hydrogel conductive but also provided abundant hydroxyl groups to form hydrogen bonds with PVA to improve the toughness of the hydrogel. Furthermore, PHMG endowed the hydrogel with antibacterial properties toward E. coli (Escherichia coli, Gram-negative bacteria) and S. aureus (Staphylococcus aureus, Gram-positive bacteria). Meanwhile, the hydrogel was implanted in mice for 14 days, and the surrounding tissue remained in good condition. More importantly, the hydrogel could detect ECG signals and electrical signals under different actions. This study affords a novel approach for exploiting wearable sensors with antibacterial properties and biocompatibility.

Hydrogel flexible sensors have attracted significant attention in wearable devices because of their inherent stretchability and good mechanical properties. However, most hydrogel sensors reported are only limited to detect strain activity based on flexible and stretchable strain sensing, which cannot provide real-time feedback on the humidity and temperature of the skin surface, this limits the scope of the application of hydrogel sensors. In this work, we fabricate an organohydrogel film sensor with a thickness of only 0.1 mm which is sensitive to humidity and temperature. The prepared organohydrogel film sensor has a wide relative humidity (RH) (20%- 90%) and temperature (-30 degrees C-50 degrees C) detection range, which can accurately record and respond to changes in humidity and temperature on the skin surface. Because of high sensitivity to humidity and temperature, the sensor can stably and repeatedly monitor human respiration with a fast response and recovery time of only 0.41 s and 0.3 s. In addition, the organohydrogel film sensor also has high transparency and anti-freezing properties, which can be precisely attached to the accurate area of skin to monitor signals at low temperatures. Therefore, this work is expected to bring new strategies to construct a new generation of electronic skin sensors and wearable devices that detect multiple stimuli.

The hydrogel exhibited concurrently enhanced mechanical properties, freezing resistance, water retention ability and biocompatibility by introducing AMY, which could serve as a wearable sensor for monitoring human motions and physiological signals.

The mutant form of the guanosine triphosphatase (GTPase) KRAS is a key driver in human tumors but remains a challenging therapeutic target, making KRAS MUT cancers a highly unmet clinical need. Here, we report a class of bottlebrush polyethylene glycol (PEG)–conjugated antisense oligonucleotides (ASOs) for potent in vivo KRAS depletion. Owing to their highly branched architecture, these molecular nanoconstructs suppress nearly all side effects associated with DNA–protein interactions and substantially enhance the pharmacological properties of the ASO, such as plasma pharmacokinetics and tumor uptake. Systemic delivery to mice bearing human non–small-cell lung carcinoma xenografts results in a significant reduction in both KRAS levels and tumor growth, and the antitumor performance well exceeds that of current popular ASO paradigms, such as chemically modified oligonucleotides and PEGylation using linear or slightly branched PEG. Importantly, these conjugates relax the requirement on the ASO chemistry, allowing unmodified, natural phosphodiester ASOs to achieve efficacy comparable to that of chemically modified ones. Both the bottlebrush polymer and its ASO conjugates appear to be safe and well tolerated in mice. Together, these data indicate that the molecular brush–ASO conjugate is a promising therapeutic platform for the treatment of KRAS -driven human cancers and warrant further preclinical and clinical development.

Conductive hydrogels are potential materials for fabricating wearable strain sensors owing to their excellent mechanical properties and high conductivity. However, it is a challenge to simultaneously enhance the mechanical properties and conductivity of hydrogels. Herein, a simple strategy was proposed for concurrently enhancing the mechanical properties and conductivity of the wearable hydrogel sensors by introducing carboxymethyl starch sodium (CMS). The introduction of CMS not only dramatically enhanced the mechanical performance of the hydrogel due to hydrogen bonding and electrostatic interaction, but also improved the conductivity of the hydrogel owing to the existence of sodium ions. As a result, the hydrogel sensors with excellent durability and stability could repeatedly detect and distinguish various human activities, including walking, chewing and speaking. Meanwhile, multiple sensors are also assembled into a 3D sensor array for detecting the three-dimensional distribution of stress and strain. Moreover, the peaks of EMG signals and the waveforms of ECG signals could be recorded because the hydrogel sensor presented super sensitivity and fast response. Therefore, the multifunctional hydrogel presented remarkable potential for applications in human medical diagnosis, health monitoring and artificial intelligence.

Herein, we demonstrate that macromonomers consisting of organics-soluble, chemically protected oligonucleotides (protDNA) and poly(ethylene glycol) (PEG) chains can be converted into bottlebrush polymers of distinct architectures via ring-opening metathesis polymerization (ROMP). Using a custom norbornene-containing phosphoramidite, two types of macromonomers were obtained: a linear norbornene-protDNA-PEG structure and a Y-shaped structure where the polymerizable norbornene group is situated at the junction where protDNA and PEG meet. With this strategy, the PEG chains can be placed either near the backbone of the bottlebrush or on its periphery, and in principle anywhere between these two extremes by adjusting the norbornene location, which makes this strategy attractive for constructing architecturally sophisticated oligonucleotide-containing copolymers.