A dual-responsive silica-based molecularly imprinted polymer for sustainable and specific adsorption of γ-aminobutyric acid from Moringa oleifera seeds.

The integration of programmable actuation with material circularity remains a critical challenge in the development of sustainable soft matter. Here, we report a dynamic covalent hydrogel that combines temperature-programmable photomorphing with closed-loop recyclability in a single material platform. The hydrogel is constructed from three dithiolane-derived components, including a spiropyran-modified thioctic acid (monomer ST), oligo(ethylene glycol)-modified thioctic acid (OEGn-T), and a crosslinker (PEG-T) containing two dithiolane end-groups linked via a polyethylene glycol chain. Upon visible-light irradiation, distinct macroscopic deformation modes, i.e., bending and then recovering or significant and fast bending without recovering, can be selectively programmed simply by adjusting the photoirradiation temperature. This temperature-programmable photomorphing behaviour arises from the interplay between spiropyran photoisomerization and lower critical solution temperature (LCST)-driven phase transition. The photomorphing function can be maintained after storage in aqueous solution or at dry ambient conditions for three weeks. Notably, the dynamic disulfide network enables efficient depolymerization under mild basic conditions, allowing recovery of up to 95% of the spiropyran-modified monomer ST, establishing a closed-loop lifecycle of monomer ST. These findings provide insights into the synergy effects of molecular isomerization and LCST-driven phase transition within dynamic disulfide networks, offering a promising strategy toward next-generation sustainable soft actuators with both sophisticated functionality and end-of-life circularity.

Molecular doping of conjugated polymers (CPs) is essential for advancing organic electronics yet achieving high and stable doping efficiency remains a significant challenge. While charge transfer, diffusion, and electronic and materials structure have been widely studied, the thermodynamic phase behavior that can fundamentally constrain doping efficiency and inform morphological stability, has received comparatively limited attention. This perspective provides an overview of the relevant thermodynamic aspects of doped CPs, including phase diagrams, miscibility limits, co-crystal formation, interaction parameters, and structural transitions, and argues for an increased focus on thermodynamic concepts. We focus on the solid, rather than the solvated state. To illustrate how thermodynamics governs CP-dopant miscibility, we draw on theoretical insights into the effective interaction parameter (χeff) for crystalline polymer systems and illustrate our arguments with experimental case studies from twelve model systems differing in sidechain chemistry, backbone structure, and energy levels. Grazing-incidence wide-angle X-ray scattering is used to probe structural transitions, while time-of-flight secondary ion mass spectrometry is used to estimate the binodal. We discuss evidence for upper and, for the first time, for lower critical solution temperature behaviors. The resultant thermodynamic perspective helps rationalize divergent behaviors across dopant-polymer combinations and provides guidance toward a generalized thermodynamic understanding that enables the co-design of CP-dopant systems with improved doping efficiency and stability. We advocate that experimental determination of the dopant polymer-phase diagram beyond the current, mostly heuristic approach and advanced modeling would greatly advance understanding and progress. We hope that this perspective will spark development of a comprehensive framework.

The rational design of functional nanomaterials requires precise control over molecular architecture and interfacial reactivity. Here, we report the synthesis of amine‐functionalized block copolymer nanoparticles via aqueous polymerization‐induced self‐assembly, combining synthetic efficiency with rigorous characterization to bridge molecular design and macroscopic functionality. The incorporation of 2‐aminoethyl methacrylate into a macrochain transfer agent enabled the formation of stable, monodisperse nanoparticles while providing quantifiable interfacial amines for postassembly modification. Near‐quantitative conjugation with fluorescein isothiocyanate (86% yield) or thermoresponsive poly(N‐isopropylacrylamide) (91% efficiency) demonstrated the platform versatility, with the latter exhibiting a tunable lower critical solution temperature transition at 41°C. Furthermore, the nanoparticles could be self‐assembled into crosslinked colloidosomes, highlighting their potential as modular building blocks for the fabrication of hierarchical architectures. This work establishes a paradigm for engineering functional polymeric nanomaterials with tailored properties, offering transformative opportunities in drug delivery, diagnostics, and nanoreactor design. By linking molecular‐scale precision to predictable performance, our approach advances the field from empirical optimization to true molecular engineering of polymeric nanoparticles.

Vision loss is one of the most debilitating eye impairments, with the leading causes such as cataracts, glaucoma, injuries to the surface of the eye and age-related macular degeneration, significantly affecting a person's quality of life and placing a substantial burden on healthcare systems. Effective treatment of these conditions remains challenging due to the complex anatomical and physiological barriers of the eye, which limit the penetration and retention of topically and intravitreally administered drugs. As a result, conventional ocular therapies often exhibit poor therapeutic efficacy, low bioavailability, necessitating frequent administration, reducing patient compliance, and increasing the risk of treatment-related complications. Thermoresponsive hydrogels have emerged as a promising class of in situ-forming drug delivery systems that utilize physiological temperature as a trigger to transition from a sol to a gel state upon administration. This sol-gel transition enhances precorneal or intraocular residence time, improves mucoadhesion, and facilitates sustained drug release. These characteristics make thermoresponsive hydrogels particularly suitable for ocular and intravitreal formulations targeting both anterior and posterior-segment diseases. Thermoresponsive polymers may exhibit lower critical solution temperature (LCST), upper critical solution temperature (UCST), or combined LCST-UCST phase behavior depending on polymer composition, enabling tunable gelation properties to control rate of drug release profiles. This review provides an overview of recent developments in thermoresponsive hydrogels for ophthalmic drug delivery, including emerging dual-responsive systems, with emphasis on gelation mechanisms, drug-release kinetics, and therapeutic applications in anterior and posterior-segment diseases. Key translational considerations, including formulation stability, sterilization, scalability, and regulatory challenges, are also discussed. In addition, the article highlights future research directions to support the continued application and clinical translation of thermoresponsive hydrogel-based ocular drug delivery systems.

Extracellular vesicles (EVs) are nanoscale lipid-bilayered structures that mediate intercellular communications by transporting nucleic acids, proteins, and lipids across diverse biological fluids. Their diagnostic potential is immense, yet their heterogeneity poses persistent challenges for isolation and characterization, often leading to low yield, co-isolation of contaminants, and vesicle damage. Here, we present a thermoresponsive polymer-integrated plasmonic metasurface sensor that enables spatiotemporally controlled, label-free EV isolation. The metasurface, engineered by repurposing nanograted optical disks, was functionalized with poly(N-isopropylacrylamide) (PNIPAM) and anti-CD63 antibodies to achieve selective EV capture at physiological temperature and gentle release upon a minute thermal change near the polymer's lower critical solution temperature (∼35°C). Using MCF-7 and HEK-293-derived EVs as a proof-of-concept, the platform exhibited a dynamic detection range spanning three orders of magnitude. Release efficiency reached 87.03 ± 23.5%, while both nanoparticle tracking analysis (NTA) and fluorescent NTA (fNTA) revealed up to ∼100-fold increase in EV purity relative to the ultrafiltration process. Electron microscopy and Western blotting confirmed preserved vesicle morphology and marker expression. By integrating thermoresponsive chemistry with a cost-effective metasurface platform, this system offers a non-destructive, portable, and real-time solution for precise EV manipulation, advancing EV-focused biosensing and point-of-care strategies for liquid biopsy applications in the future.

The potential of soft actuators for tasks in complex environments remains constrained by their lack of real-time proprioceptive capabilities. Here, this challenge is addressed through a multimaterial digital light processing (DLP) 3D printing strategy for constructing bilayer actuators integrating thermoresponsive actuation with strain-sensing functions. Two photocurable functional inks were developed and integrated into a single heterogeneous bilayer system via multimaterial DLP 3D printing. The passive layer consists of a dual-network ionoelastomer based on a polymerizable deep eutectic solvent (PDES) and carboxymethyl cellulose (CMC), with favorable mechanical properties (tensile strength ∼0.5 MPa) and sensitive strain-sensing performance (gauge factor = 2.11). The active layer is composed of a functionalized poly(N-isopropylacrylamide) hydrogel; the incorporation of a DES synergistically enhanced its mechanical performance (compressive strength ∼1.05 MPa) while enabling effective regulation of the lower critical solution temperature (LCST: 32-46 °C). Seamless integration and robust interfacial bonding between these heterogeneous materials were achieved by systematically optimizing the printing process. The resulting bilayer actuators demonstrated efficient and tunable thermoresponsive actuation, with programmable complex deformations realized through the structural design of the active layer. Furthermore, the integrated sensing capabilities enabled self-perception, allowing the actuator to monitor its own deformation states during actuation. This multimaterial DLP 3D printing strategy established a material and processing foundation for the construction of intelligent soft systems with proprioceptive capabilities.

Liposomes, nanosized vesicles consisting of a lipid bilayer membrane, have been widely investigated as versatile drug delivery systems. Clinically, several liposomal formulations have been used as anticancer drug carriers owing to their enhanced permeability and retention (EPR) effects. Nevertheless, the accumulation of conventional liposomes in tumors remains insufficient to achieve optimal therapeutic efficacy. Therefore, the development of innovative liposomes with improved tumor selectivity and delivery efficiency is required. In this study, we designed and evaluated novel liposomes prepared from thermoresponsive polyoxazoline (POZ)-lipid conjugates (DSPE-POZ), cholesterol, and hydrogenated soybean phosphatidylcholine (HSPC). The obtained liposomes had a particle size of 50-60 nm and a slightly negative ζ-potential. POZ has a lower critical solution temperature (LCST), which enables liposomes to alter their physicochemical properties in response to mild hyperthermia. The fixed aqueous layer thickness (FALT) of the DSPE-POZ liposomes dramatically decreased above the LCST, indicating increased hydrophobicity of the liposomal surface. A cellular uptake study using mouse colon cancer cells (Colon26) demonstrated that DSPE-POZ liposomes containing POZ with an LCST of 37-38 °C were significantly highly taken up by tumor cells at 43 °C (above LCST) compared to 37 °C. Furthermore, biodistribution studies using Colon26 tumor-bearing mice revealed that DSPE-POZ liposomes were cleared from the blood and preferentially accumulated in heated tumors, achieving a 7-fold higher uptake than in nonheated tumors. These results indicate that liposomes composed of POZ-lipid conjugates represent a promising drug delivery platform capable of improving tumor accumulation when combined with local tumor heating.

It is still challenging to enable a precise and editable hydrogel design by quantitatively relating the molecular composition and hierarchy with the properties and functions. Herein, a programmable hydrogel system was successfully produced by copolymerizing N-isopropylacrylamide (NIPAM) with N, N'-dimethylacrylamide (DMAA) and acrylamide (AM), combined with the physical entanglement effect of hydroxypropyl cellulose (HPC). The incorporation of DMAA increased the hydrophilicity of the network, enabling precise adjustment of the lower critical solution temperature (LCST) within the range of 34°C∼49°C. The compressive modulus decreased from 18.3 to 12.3kPa with increasing DMAA content, while the incorporation of AM significantly improved the compressive modulus from 16.2 to 24.0kPa and reduced the mechanical loss rate to only 3.6% after 100 compressive cycles. The application of the hydrogel in information encryption was demonstrated by utilizing its quick and reversible transparent-opaque transition to achieve temperature-dependent quick response (QR) code encryption and dynamic password display. A soft actuator capable of rapid thermally induced bending was developed by constructing a bilayered poly(N-isopropylacrylamide)-co-poly(N,N-dimethylacrylamide)/poly(N-isopropylacrylamide)-co-poly(N,N-dimethylacrylamide-co-acrylamide) (P(NIPAM-co-DMAA)/P(NIPAM-co-DMAA-co-AM))structure with a modulus gradient. Finite element simulation confirmed the exponential relationship between the bending curvature and the interlayer modulus difference. This study provides a simple and rational strategy for designing a smart hydrogel platform.

Modelling the impact of temperature on nanocarrier behavior: Thermodynamics, structural transitions, and drug release.

Biomolecular condensates play crucial roles in cellular organization and are emerging as versatile platforms for biomedicine. However, their limited pH stability constrains functionality across diverse physiological environments. Here, we report a molecular shielding strategy to achieve tunable coacervation of simple amino acids over a wide pH range (1.0-13.0). To be specific, selective modification of terminal ionizable groups blocks pH-induced charge variations, thereby leading to phase behavior independent of environmental pH. In addition, such amino acid-based coacervates possess distinct thermoresponsive features, displaying either elastin-like lower critical solution temperature (LCST) or prion-like upper critical solution temperature (UCST) phase transitions. In particular, the programmable pH-responsive feature permits biocompatible N-terminal shielding phenylalanine coacervates to remain stable under harsh gastric conditions and prolonged gastrointestinal drug retention. As a result, highly efficient oral delivery and therapy in acute colitis are achieved in vivo. This work opens a new avenue to construct programmable coacervates responding to physiological environmental changes for biomedical applications.

Stimuli-responsive hydrogels have gained significant attention as one of the most attractive materials for soft robots. Herein, a facile, printable thermo-responsive hydrogel (NL hydrogel) with rapid volume change capability and excellent mechanical properties was developed through the self-assembly of poly(N-isopropylacrylamide) (PNIPAM) and hydrophobic lignin. The lignin and PNIPAM self-assembled into a hierarchical phase-separated structure consisting of lignin-rich dense regions with a bicontinuous morphology and PNIPAM-rich, chain-sparse regions. This unique architecture results in multiscale water channels, enabling an ultrafast dehydration response (expelling 90% of its water within 10 s) and an ultrahigh volume shrinkage of up to 96.4% above its lower critical solution temperature (LCST). The phase separation structure also endows the NL hydrogels with outstanding mechanical properties, achieving tensile stress and strain values exceeding 1 MPa and 500% below the LCST, and approximately 5 MPa and 1500% above the LCST. The responsive speed and mechanical properties of the NL hydrogels surpass those of most reported thermo-responsive hydrogels. The NL hydrogels can be readily printed via direct ink writing into various geometries. The printed NL hydrogels demonstrate thermo-triggered shape morphing, functioning as temperature-controlled actuators with adjustable curvature and as manipulators for capture, wrapping, encapsulation, and switching. Furthermore, the photothermal effect of lignin enables light-controlled actuation of the NL hydrogel.

Accurate 3D dynamic monitoring of thermosensitive hydrogel phase transitions remains challenging due to large deformations and high noise levels. We present a deep learning-enhanced dual-wavelength digital holographic method that overcomes noise amplification in synthetic-wavelength phase maps using an adapted multi-feature fusion unwrapping network, enabling robust phase retrieval under strong speckle noise. The experiments on hydrogels reveal the distinct contraction kinetics below and above the lower critical solution temperature, and a quantitative empirical model linking volume with temperature and time is established. This work provides a precise, wide-range, 3D dynamic measurement platform for soft matter studies and supports the design of hydrogel-integrated adaptive thermal-management systems.

ABSTRACT Intelligent thermal management is essential for battery safety in sustainable development. Herein, we incorporate the “intelligence” property into aqueous zinc‐ion batteries (AZIBs) by introducing a thermo‐responsive graphene oxide/hydroxypropyl cellulose (GO/HPC) composite membrane as a smart thermal protection component. The as‐prepared membrane demonstrates exceptional flexibility and mechanical robustness, with a Young's modulus of 3.3 GPa. Taking advantage of the reversible lower critical solution temperature (LCST)‐driven phase transition of HPC, the membrane undergoes autonomous shrinkage and ionic shutdown when the ambient temperature reaches 65°C‐triggering an immediate self‐protective state to suppress thermal runaway in AZIBs. Mechanistically, the conformational transition of HPC (from hydrophilic extended chains to hydrophobic globules) upon heating simultaneously blocks Zn 2+ transport and water permeation across the membrane, while the amphiphilic GO surface guides the ordering of liquid crystalline HPC domains to optimize this dual‐functional switching behavior. Notably, AZIBs integrated with this intelligent membrane retain 92% and 80% of their initial capacity after a single thermal shutdown‐cooling cycle and after 15 repeated shutdown‐recovery cycles, respectively, confirming the reversibility of the membrane's thermo‐responsive behavior. This work provides a rational material design paradigm for the safety of AZIBs, facilitating their use in practical applications from consumer electronics to large‐scale grid energy storage.

The wide applications of proteinosomes as protocells and nanoreactors benefit from their capsule-like structures and protein functions. In regular proteinosomes, the hydrophilic protein corona can be denatured in unfavorable conditions, such as extreme pH and protease. Herein, proteinosomes with a PEG protein mixed corona are prepared to protect the protein's biofunction. The block copolymer polyethylene glycol-block-poly(di(ethylene glycol) methyl ether methacrylate) (PEG-b-PDEGMA) bearing an adamantyl group at the junction undergoes molecular recognition with β-cyclodextrin-modified proteins, affording miktoarm polymer-protein conjugates. β-Galactosidase (β-gal) and glucose oxidase (GOx) were chosen as model proteins. Conjugates PEG-b-PDEGMA/β-gal, PEG-b-PDEGMA/GOx, and their mixture (PEG-b-PDEGMA/β-gal/GOx) self-assembled into proteinosomes consisting of a PDEGMA membrane and a PEG protein mixed corona at temperatures above their lower critical solution temperatures. The activities of enzymes in all the proteinosomes were well preserved, and the mixed corona proteinosomes exhibited more effective protection against extreme pH conditions and trypsin digestion than the regular ones.

As a type of intelligent polymer with significant application potential, lower critical solution temperature (LCST)-type hydrogels have shown broad application prospects in fields such as thermal management, biomedicine, and intelligent devices, due to theirs high water content, thermally responsive phase transitions, and tunable properties. This article elaborates in detail the molecular mechanism, thermodynamic principles of the phase transition, and the equations of thermal performance. On this basis, it comprehensively summarizes the strategies for adjusting the LCST temperature, improving its stability and multifunctionality, for help researchers gain a deeper understanding of LCST-type hydrogels. Moreover, it is also shown that this manuscript provides a comprehensive overview of typical applications of LCST hydrogels, including controlled drug delivery, tissue engineering, sensing and detection, thermal management, energy utilization and conservation, as well as smart textiles. Finally, the great capability of LCST-type hydrogels and future perspectives in this field are outlined. This review aims to establish a systematic design framework and offer practical guidance for the rational development and performance optimization of next-generation LCST-type phase-change hydrogels, while also highlighting their promising prospects for application across multiple fields.

Cononsolvency generally refers to the phase separation of a homopolymer solution in mixtures of two miscible good solvents. While commonly observed in systems with a lower critical solution temperature (LCST), it also occurs in systems lacking specific interactions or LCST behavior. Recent coarse-grained polymer models and the classical Flory-Huggins (FH) theory used to study cononsolvency consider only chain connectivity, excluded-volume repulsion, and isotropic van der Waals attractions, with constant nonbonded interaction parameters─making them especially suitable for systems exhibiting an upper critical solution temperature (UCST). However, the role of solvent entropy, particularly the size ratio between the solvent and cosolvent molecules, has been largely overlooked. Extending recent work by one of us (Zhang, P. Macromolecules 2024, 57, 4298; ibid. 2025, 58, 2472), we incorporate this entropic effect into the ternary FH theory and find that it significantly broadens the parameter space where cononsolvency occurs in UCST systems.

Thermoresponsive electrospun scaffolds based on poly-(N-isopropylacrylamide) (PNIPAM) copolymers exhibit morphology-dependent structural disintegration upon cooling to the temperature of the coil-to-globule transition. This behavior does not coincide directly with the classical lower critical solution temperature (LCST) or volume phase transition temperature (VPTT) due to the specific fiber architecture formed by electrospinning. In this study, the Scaffold Disintegration Temperature (SDT) is introduced as an operational descriptor corresponding to the onset of reproducible morphological collapse in fibrous PNIPAM networks. SDT is used as a comparative metric to assess how the macromolecular architecture and processing conditions relate to the scaffold-level stability. Using viscosity-matched statistical and graft copolymers with distinct topologies, architecture-dependent differences in the disintegration behavior were identified. These differences correlate with variations in network morphology and orientational coherence. Scaffolds based on graft copolymers bearing rigid (PLA) or flexible (PCL) side chains exhibited earlier structural disintegration during cooling and reduced network coherence, whereas the statistical P-(NIPAM-co-NtBA) system maintained structural integrity over a broader temperature interval and showed greater mechanical robustness under comparable conditions. A variation of the nozzle-to-collector distance further modulated the architecture-dependent differences in the fiber morphology, porosity, and mechanical performance but did not override the dominant influence of macromolecular topology. These results establish SDT as a network-level, morphology-dependent parameter that complements LCST in describing the thermal behavior of electrospun PNIPAM-based materials.

Construction dual-temperature responsive hydrogel of hydroxypropyl methylcellulose and κ-carrageenan via formation of dynamic semi-interpenetrating physical structure.

Recently, researchers' attention has been drawn to reversible surface superwettability with ultrafast responsiveness to environmental stimuli, since these platforms show great promise for a variety of applications. Herein, thermoresponsive electroconductive PDMS modified by poly(N-isopropylacrylamide) (PNIPAAm) and carbon black has been developed (PNIPAAm@C@PDMS sponge). The incorporation of PNIPAAm rendered the fluoride-free PDMS sponge temperature-sensitive, enabling a convertible wettability. The porous structure of the PDMS sponge facilitated the addition of carbon black to enhance surface roughness and impart electrical conductivity, creating numerous active sites capable of adsorbing PM pollutants. The carbon black composition has endowed the obtained sponge with a certain conductivity, exhibiting excellent Joule heating performance at a voltage of 24 V. Dependent upon this property, a smart switch of superwettability can be achieved for PNIPAAm@C@PDMS by self-induced joule heating. The composite sponge shows superhydrophilicity and underwater superoleophobicity below the lower critical solution temperature (LCST, ca. 25 °C), which can be used to separate different types of water-in-oil mixtures. However, the reverse characteristic above the LCST (ca. 45 °C) can be observed, displaying superhydrophobicity and underwater superoleophilicity, which allows it to separate a stabilized oil-in-water mixture. Besides, the composite sponge also shows excellent potential recyclable filtration performance for PM2.5. Importantly, the PNIPAAm coating provides a stable superhydrophobic surface that ensures long-term PM filtration stability under high-humidity conditions, demonstrating that the smart wettability design indirectly but crucially supports air purification applications. Therefore, the smart switchable sponge can be a promising candidate for developing multifunctional superwettable surfaces for water and air pollution treatment.