Temperature-sensitive Properties Research Articles

Effect of Ti3C2Tx MXenes on the structure, morphology, fluorescence and temperature-sensitive properties of Eu3+-doped (YSZ)0.3-(YTaO4)0.7 rare-earth high-temperature ceramic powders

The rapid development of rare-earth fluorescent materials based on the fluorescence intensity ratio method allows the monitoring of internal temperature, stability and service life of thermal barrier coatings (TBCs). In this paper, Eu3+ doped (YSZ)0.3-(YTaO4)0.7 rare-earth ceramic materials was firstly prepared by chemical co-precipitation technique, and the doping content of Eu3+ was optimized by comparing its effect on morphology, luminescence and temperature sensitive performance of (YSZ)0.3-(YTaO4)0.7. Then the Ti3C2Tx MXene was subsequently blended into the optimal (YSZ)0.3-(YTaO4)0.7: Eu3+ powders by mechanical milling. The influence of Ti3C2Tx MXenes on the structure, morphology, fluorescence properties and temperature sensitivity of (YSZ)0.3-(YTaO4)0.7: Eu3+ powders was further investigated systematically. Results showed that (YSZ)0.3-(YTaO4)0.7: Eu3+ powders were compound of M′-YTaO4 and YSZ in tetragonal phase. The optimal doping content of Eu3+ is 1.5 mol%. The adding of Ti3C2Tx MXene did not affect the structure of (YSZ)0.3-(YTaO4)0.7:Eu3+ powders. After addition of Ti3C2Tx MXenes, part of (YSZ)0.3-(YTaO4)0.7:Eu3+ particles embedded in the middle of the accordion-shaped MXenes sheet, while the other part wrapped around MXenes. Ti3C2Tx MXenes could significantly improve the luminescence intensity, fluorescence lifetime and temperature-sensitive performance of (YSZ)0.3-(YTaO4)0.7: Eu3+powders. The optimal addition amount of Ti3C2Tx MXenes is 0.6 wt%. The absolute and relative sensitivities of MXene/(YSZ)0.3-(YTaO4)0.7:Eu3+ powders archived 2 times of (YSZ)0.3-(YTaO4)0.7: Eu3+ powders. Therefore, MXene/(YSZ)0.3-(YTaO4)0.7: Eu3+ could be used as temperature-indicating ceramic materials with highly efficient fluorescent properties for real-time monitoring of internal temperature of TBCs.

Rapid temperature response of polymer-derived SiBCN ceramics

Polymer-derived SiBCN ceramics with good high-temperature stability and temperature-sensitive properties can be used in real-time temperature monitoring in the aeronautical industry. However, previous investigations mostly focus on the temperature sensitivity of SiBCN ceramics but neglect the fast temperature conversion of the real operating environment and its effect on the temperature sensitivity, which hinders their further practical application. In this study, the response to rapid temperature changes of polymer-derived SiBCN was studied. SiBCN ceramics maintain excellent high-temperature semiconductor performance under rapid heating, and its direct-current (DC) conductivity increases with increasing temperature. The conductive mechanism conforms to the amorphous semiconductor formula, following three different transition mechanisms in different temperature regions. The resistance of SiBCN increases with the number of cycles during 100 cycles of 500–1200 °C, presenting excellent temperature-sensitivity and relatively good sensing stability. This work demonstrates that SiBCN ceramics can maintain excellent temperature-resistance under extreme environments with rapid heating and cooling, and it is hoped that this work could guide the development of temperature sensors for extreme environments in the future.

Fabrication of Hierarchical Assemblies through Temperature-Triggered Liquid Crystallization Driven Self-Assembly.

Functional hierarchy is prevalent in biological systems owing to natural evolution. Efforts to replicate these structures in artificial materials have gained traction in materials science. Although artificial hierarchical structures are fabricated at different scales based on site-specific interactions using ABC-type block copolymers (BCPs), the fabrication of such hierarchical structures using AB-type BCPs via a simple and efficient method remains challenging. Herein, a class of amphiphilic BCPs (PDenm-b-PACholn) is reported comprising dendronized oligoethylene glycol (Den) and cholesterol (AChol) as hydrophilic and hydrophobic moieties, respectively. By employing the collapse of PDenm blocks at a specific temperature, the fabrication of bundled fibers and multilayer vesicles is achieved with an obvious hierarchy. Different from common reversible aggregation-disaggregation processes of thermal-responsive polymers, the ordering of the core-forming block with liquid crystalline (LC) properties provides robustly physical cross-linking, coupled with epitaxial growth and the lateral fusion of LC blocks, guiding the formation of stable hierarchical micellar structures. It is highlighted that the combination of temperature-sensitive properties and LC ordering alignment offers a novel approach for constructing hierarchical structures using AB-type BCPs via an efficient one-step assembly method.

Porous hydrogel microspheres with excellent temperature-sensitive, magnetic and fluorescent properties for drug delivery.

Porous hydrogel microspheres with temperature-sensitive, magnetic and fluorescent properties have great potential for drug delivery. In this study, porous hydrogel microspheres with excellent temperature-sensitive, magnetic and fluorescent properties were prepared through droplet microfluidics and photoinitiated radical polymerization, which were characterized via scanning electron microscopy (SEM), vibrating sample magnetometry (VSM), fluorescence spectroscopy, ultraviolet spectrophotometry, and other techniques. The volumetric phase-transition temperature of porous hydrogel microspheres was in the range of 40-45 °C, and the volume swelling ratio reached 5.26 as the temperature decreased from 55 °C to 25 °C. Meanwhile, the saturation magnetization and optimal fluorescence emission wavelength of porous hydrogel microspheres were 1.79 emu g-1 and 616 nm, respectively, which can be an effective strategy to visually monitor and control the speed of drug release during magnetic heat therapy. Finally, bovine serum albumin (BSA) was employed as a model drug to investigate the drug loading and release of porous hydrogel microspheres. The maximal drug loading amount was 238 mg g-1, and the drug release speed and amount can be correspondingly promoted by altering the temperature.

Preparation and Analysis of Structured Color Janus Droplets Based on Microfluidic 3D Droplet Printing.

The microfluidic technique for the three-dimensional (3D) printing of Janus droplets offers precise control over their size, orientation, and positioning. The proposed approach investigates the impact of variables such as the volume ratio of the oil phase, droplet size, and the ratio of nonionic surfactants on the dimensions of the structured color apertures of Janus droplets. The findings reveal that structured color apertures modulate accurately. Furthermore, fabricating color patterns facilitates cat, fish, and various other specific shapes using structured color Janus droplets. The color patterns exhibit temperature-sensitive properties, enabling them to transition between display and concealed states. Herein, the adopted microfluidic technique creates Janus droplets with customizable characteristics and uniform size, solving orientation as well as space arrangement problems. This approach holds promising applications for optical devices, sensors, and biomimetic systems.

Thermosensitive black phosphorus hydrogel loaded with silver sulfadiazine promotes skin wound healing

Wounds can lead to skin and soft tissue damage and their improper management may lead to the growth of pathogenic bacteria at the site of injury. Identifying better ways to promote wound healing is a major unmet need and biomedical materials with the ability to promote wound healing are urgently needed. Here, we report a thermosensitive black phosphorus hydrogel composed of black phosphorus nano-loaded drug silver sulfadiazine (SSD) and chitosan thermosensitive hydrogel for wound healing. The hydrogel has temperature-sensitive properties and enables the continuous release of SSD under near-infrared irradiation to achieve synergistic photothermal and antibacterial treatment. Additionally, it exerts antibacterial effects on Staphylococcus aureus. In a rat skin injury model, it promotes collagen deposition, boosts neovascularization, and suppresses inflammatory markers. In summary, the excellent thermosensitivity, biocompatibility, and wound-healing-promoting qualities of the reported thermosensitive hydrogel make it suitable as an ideal wound dressing in the clinic.

In Vitro Enzymatic Studies Reveal pH and Temperature Sensitive Properties of the CLIC Proteins.

Chloride intracellular ion channel (CLIC) proteins exist as both soluble and integral membrane proteins, with CLIC1 capable of shifting between two distinct structural conformations. New evidence has emerged indicating that members of the CLIC family act as moonlighting proteins, referring to the ability of a single protein to carry out multiple functions. In addition to their ion channel activity, CLIC family members possess oxidoreductase enzymatic activity and share significant structural and sequence homology, along with varying overlaps in their tissue distribution and cellular localization. In this study, the 2-hydroxyethyl disulfide (HEDS) assay system was used to characterize kinetic properties, as well as the temperature and pH profiles of three CLIC protein family members (CLIC1, CLIC3, CLIC4). We also assessed the effects of the drugs rapamycin and amphotericin B, on the three CLIC proteins' enzymatic activity in the HEDS assay. Our results demonstrate CLIC1 to be highly heat-sensitive, with optimal enzymatic activity observed at neutral pH7 and at a temperature of 37 °C, while CLIC3 had higher oxidoreductase activity in more acidic pH5 and was found to be relatively heat stable. CLIC4, like CLIC1, was temperature sensitive with optimal enzymatic activity observed at 37 °C; however, it showed optimal activity in more alkaline conditions of pH8. Our current study demonstrates individual differences in the enzymatic activity between the three CLIC proteins, suggesting each CLIC protein is likely regulated in discrete ways, involving changes in the subcellular milieu and microenvironment.

Temperature-sensitive multifunctional intelligent responsive hydrogel based on carboxymethyl agarose and N-isopropylacrylamide: Controlled drug release and accelerated wound healing

Wound healing remains challenging due to posttraumatic pain. At present, most wound dressings ignore the importance of wound pain. In this study, a temperature-sensitive multifunctional intelligent hydrogel patch (CPAG) containing lidocaine has developed for wound healing. CPAG hydrogel was prepared by grafting N-isopropylacrylamide and acrylamide onto carboxymethyl agarose (CMA) modified by agarose and encapsulating gallic acid and lidocaine. FTIR, 1H NMR spectroscopy, SEM and rheology were used to investigate its structure and temperature-sensitive properties. The contraction force generated by the temperature response characteristics of CPAG at 30 °C can accelerate wound healing. In vitro release assays demonstrated that CPAG directly controlled the same amount of lidocaine release at different temperatures through the competition between polymer-polymer and polymer-water interactions. In addition, MTT, H&E staining and stimulation test further proved its biological safety. The pain behavior study showed that the pain inhibition rates of the lidocaine cataplasms and LID@CPAG were 51.16 % and 67.83 %, respectively. In vitro and in vivo studies have shown that compared with the blank group, the bleeding volume of LID@CPAG decreased by 54.3 %, and the wound healing rate reached 97 %. CPAG hydrogel can play a comprehensive therapeutic role in accelerating wound closure by controlling drug release, analgesia, antioxidation and hemostasis.

Design of Surface Plasmon Resonance-Based D-Type Double Open-Loop Channels PCF for Temperature Sensing.

Here, we document a D-type double open-loop channel floor plasmon resonance (SPR) photonic crystal fiber (PCF) for temperature sensing. The grooves are designed on the polished surfaces of the pinnacle and backside of the PCF and covered with a gold (Au) film, and stomata are distributed around the PCF core in a progressive, periodic arrangement. Two air holes between the Au membrane and the PCF core are designed to shape a leakage window, which no longer solely averts the outward diffusion of Y-polarized (Y-POL) core mode energy, but also sets off its coupling with the Au movie from the leakage window. This SPR-PCF sensor uses the temperature-sensitive property of Polydimethylsiloxane (PDMS) to reap the motive of temperature sensing. Our lookup effects point out that these SPR-PCF sensors have a temperature sensitivity of up to 3757 pm/°C when the temperature varies from 5 °C to 45 °C. In addition, the maximum refractive index sensitivity (RIS) of the SPR-PCF sensor is as excessive as 4847 nm/RIU. These proposed SPR-PCF temperature sensors have an easy nanostructure and proper sensing performance, which now not solely improve the overall sensing performance of small-diameter fiber optic temperature sensors, but also have vast application prospects in geo-logical exploration, biological monitoring, and meteorological prediction due to their remarkable RIS and exclusive nanostructure.

Temperature-sensitive and amphiphilic silica nanoparticle-stabilized Pickering emulsion for water shutoff

Due to the shale matrix's low permeability and narrow pore throats, conventional Pickering emulsion plugging agents are unable to effectively seal the formation, making it challenging to create a reliable mud cake that prevents fluid penetration. To address this issue, SiO2 nanoparticles (PEG200-SiO2-OTES) with amphiphilic and temperature-sensitive properties were synthesized for this study. These modified particles were used to prepare temperature-sensitive Pickering emulsions. The aim was to use the emulsion as a carrier to transport the nanoparticles to the specified stratum to release and seal the pore throat. This temperature-sensitive smart Pickering emulsion-based plugging agent (POOP) is used to water shutoff. The produced material had a particle size of around 20 nm, according to structural studies, and had a sensitive temperature response (response temperature of 80 °C). Furthermore, laboratory tests and characterizations revealed that the average diameter of the POOP emulsion droplets was measured to be 1.62 µm, with the emulsion exhibiting a response temperature for breakage at approximately 80 °C.The plugging agent could release PEG200-SiO2-OTES particles at the response temperature of the formation. At this temperature, the plugging agent particles undergo a transition from hydrophilic to hydrophobic, effectively sealing the low permeability (100 mD) and high permeability (1000 mD) formations with sealing efficiencies of up to 83.56% and 75.07% respectively.

Embryonic perfect repair inspired electrospun nanofibers dressing with temperature-sensitive and antibacterial properties for wound healing.

The development of highly effective wound dressings is crucial for successful clinical applications. Achieving wound closure, preventing infection, and minimizing scarring are key objectives in wound healing. Drawing inspiration from the regenerative mechanisms observed in embryonic tissue repair, we designed a series of wound-contractible dressings with exceptional antibacterial properties. This was achieved by encapsulating quaternized silicone (QP12) and poly(N-isopropylacrylamide-co-N-hydroxymethylacrylamide-co-octadecyl acrylate) (PNNS) within electrospun nanofibers of poly(ε-caprolactone) (PCL). The resulting nanofibrous dressings demonstrated remarkable thermo-responsive self-contraction and tissue adhesion capabilities, enabling secure adherence to the skin and active wound closure. Notably, these nanofibers exhibited potent antibacterial activity against both Gram-positive and Gram-negative bacteria. Furthermore, they possessed desirable properties such as hydrophilicity, biocompatibility and mechanical properties resembling human skin. A full-thickness skin defect model evaluation revealed that these temperature-sensitive nanofibers expedited wound closure, enhanced wound healing, and suppressed scar formation. This result was evidenced by reduced infiltration of inflammatory cells, well-organized collagen arrangement, and improved vascularization. In summary, we propose that these wound-contractible nanofibers, with their antibacterial and anti-scarring properties, hold great promise as an advanced solution for skin wound repair.

Effects of Ti3C2Tx MXene on structure, morphology, fluorescence and temperature sensitive properties of Eu3+ doped 8YSZ powder

Effects of Ti3C2Tx MXene on structure, morphology, fluorescence and temperature sensitive properties of Eu3+ doped 8YSZ powder

Synthesis of graphene quantum dots with temperature-sensitive properties from sea rice for rapid and highly selective detection of 4-nitrophenol

Synthesis of graphene quantum dots with temperature-sensitive properties from sea rice for rapid and highly selective detection of 4-nitrophenol

Live Mycobacterium paragordonae induces heterologous immunity of natural killer cells by eliciting type I interferons from dendritic cells via STING-dependent sensing of cyclic-di-GMP

Exploiting the heterologous effects of vaccines is a feasible strategy to combat different pathogens. These effects have been explained by enhanced immune responses of innate immune cells. Mycobacterium paragordonae is a rare nontuberculosis mycobacterium that has temperature–sensitive properties. Although natural killer (NK) cells exhibit heterologous immunity features, the cellular crosstalk between NK cells and dendritic cells (DCs) during live mycobacterial infection has remained elusive. We show that live but not dead M. paragordonae enhances heterologous immunity against unrelated pathogens in NK cells by IFN-β of DCs in both mouse models and primary human immune cells. C-di-GMP from live M. paragordonae acted as a viability-associated pathogen-associated molecular pattern (Vita-PAMP), leading to STING-dependent type I IFN production in DCs via the IRE1α/XBP1s pathway. Also, increased cytosolic 2′3′-cGAMP by cGAS can induce type I IFN response in DCs by live M. paragordonae infection. We found that DC-derived IFN-β plays a pivotal role in NK cell activation by live M. paragordonae infection, showing NK cell-mediated nonspecific protective effects against Candida albicans infection in a mouse model. Our findings indicate that the heterologous effect of live M. paragordonae vaccination is mediated by NK cells based on the crosstalk between DCs and NK cells.

Support-less ceramic 3D printing of bioceramic structures using a hydrogel bath

Volumetric bone tissue defects are beyond the intrinsic regenerative capacity of bone tissue. With the recent development of ceramic 3D printing, various bioceramic scaffolds that can induce bone regeneration are being actively developed. However, hierarchical bone is complex, with overhanging structures that require additional sacrificial support during ceramic 3D printing. Not only can this increase the overall process time and material consumption, but breaks and cracks may occur when sacrificial supports are removed from fabricated ceramic structures. In this study, a support-less ceramic printing (SLCP) process using a hydrogel bath was developed to facilitate the manufacture of complex bone substitutes. A hydrogel bath, consisting of pluronic P123 with temperature-sensitive properties, mechanically supported the fabricated structure when the bioceramic ink was extruded into the bath and promoted the cement reaction to cure the bioceramic. SLCP enables the fabrication of complex bone constructs with overhanging structures, such as the mandible and maxillofacial bones, with reduced overall processing time and material consumption. Scaffolds fabricated by SLCP showed more cell adhesion, higher cell growth rate, and osteogenic protein expression due to their rougher surface than conventionally printed scaffolds. Hybrid scaffolds were fabricated by SLCP to co-print cells and bioceramics, and SLCP provided a cell-friendly environment, exhibiting high cell viability. SLCP enables control of the shape of various cells, bioactive substances, and bioceramics and thus can be used as an innovative 3D bioprinting technique to manufacture complex hierarchical bone structures.

Physicochemical investigations on the interaction of an anionic surfactant with cellulose based polymer microgel

Abstract This work focuses on the interaction of cellulose-based colloidal microgel dispersions with the anionic surfactant sodium dodecyl sulfate (SDS) at different concentrations. First, a Cellulose-P(NIPAAm-MAA)-based responsive microgel sample was prepared by a radical polymerization method using a one-pot process. The samples thus obtained were purified, characterized and used to study microgel-surfactant interactions. To this end, SDS solutions with different concentrations were prepared and the interactions of SDS in the premicellar and micelle regions with polymer microgel were investigated using different physicochemical techniques. Experiments were also performed at different temperatures to obtain the degree of binding of SDS to microgel in gel surfactant mixtures. Due to the temperature-sensitive properties of microgel, we observed significant changes in various properties of microgel-surfactant mixtures when the solution temperature changed. The overall results showed that various experimental variables, such as the polymer gel/surfactant ratio and temperature, affect the gel–surfactant interaction quantitatively and qualitatively. With increasing surfactant concentration, conductance, viscosity and absorbance values ​​increased, but a decrease in surface tension was observed. This is due to the adsorption of SDS at the air-water interface. The micellar activity of surfactants is enhanced by the addition of microgels. It was found that the strength and nature of the interaction depended not only on the gel/surfactant ratio, solvent type and test temperature, but also on the chemical structure of the surfactant used. Furthermore, the visual stability of the colloidal particles in the mixture of microgel and SDS was also noticeable over time.

Excellent Sensitive Temperature Sensing Performance Based on Fluorescence Intensity Ratio Technique of Yb3+/Er3+ Codoped Gd2(WO4)3

For noncontact temperature sensing, the fluorescence intensity ratio (FIR) technique based on thermally coupled levels has great prospects. Within this technique, Yb3+/Er3+ codoped upconversion (UC) particles are regarded as efficient material. Juanqin Xue and co-workers (article number 2200471) have prepared Yb3+/Er3+ codoped Gd2(WO4)3 particles by a facile coprecipitation method and subsequent calcination. The crystal structure, microstructure, and UC emission of the particles are studied in detail, and the optimum temperature sensing performance is systematically measured. Excellent temperature-sensitive properties of Gd2(WO4)3:Yb3+/Er3+ demonstrate great potential for its application in noncontact optical temperature sensors.

Self-collected 3D nano-adsorbent GR@p(POSS-co-DMAEMA) applied to the dispersive solid-phase microextraction in parabens detection of condiments

In this work, we rationally designed a facile dispersible and self-collectible nano-adsorbent GR@p(POSS-co-DMAEMA) to simplify the dispersive solid-phase microextraction (DSPME). The difficulty of allowing close contact between the nano-adsorbent and donor sample solution was solved, thus improving the extraction efficiency. Furthermore, the GR@p(POSS-co-DMAEMA) with temperature-sensitive property can self-collect at high temperature, simplifying the DSPME steps (7 min). Fabrication and dispersity of GR@p(POSS-co-DMAEMA) were certified by characteristic analyses. Based on above, a method for analyzing four parabens by GR@p(POSS-co-DMAEMA)-DSPME combined with HPLC-UV was established. The feasibility of the method was verified in simulated water targeting four parabens with good precision (RSD%, 1.7–11.3, n = 3) and low detection limits (0.29–0.63 ng mL−1) under optimal conditions. The method was successfully applied to analyze three condiments and obtained relative recoveries between 91.20 and 133.71%. The results showed that the proposed method is promising to be a fast, efficient and reliable method for the trace analysis of parabens.

Effect of phenolic acids on temperature-sensitive property of self-assembly of ionic pair of poly(ethylene imine)/(phenylthio)acetic acid

The ionic pair self-assembly (IPSAM) composed of poly(ethyleneimine) (PEI) and (phenylthio)acetic acid (PTA) was prepared and the effect of phenolic acids (PAs) (e.g. cinnamic acid (CA), hydroxycinnamic acid (HCA), and dihydroxycinnamic acid (DHCA)) on the upper critical solution temperature (UCST) and the temperature-responsive releasing property of IPSAM were investigated. PEI/PTA ionic pair showed a UCST behavior and the PAs decreased the UCST effectively in the order of DHCA > HCA > CA. The PAs were thought to attach to the PEI chain of PEI/PTA ionic pair as pendants. PEI/PTA(3/7) ionic pair was found to be air/water interface-active. CA had little effect on the interfacial activity of the ionic pair. HCA and DHCA significantly decreased the interfacial activity. IPSAM was found as nanoparticles whose diameter was tens of nanometer and PAs had little effect on the shape and the size of IPSAM. The release degree of cargo loaded in IPSAM increased slowly with time lapse when below UCST. Whereas, the release degree increased rapidly with time lapse when above UCST, possibly because of the thermally-induced disintegration of IPSAM.

In situ administration of temperature-sensitive hydrogel composite loading paclitaxel microspheres and cisplatin for the treatment of melanoma

Chemotherapy is one of the main therapeutic strategies for the treatment of malignant melanoma. Conventional chemotherapeutic agents often lack targeting abilities, and efficacy is hampered by their high toxic effects to normal tissues and rapid clearance from the circulation. In this study, porous paclitaxel (PTX)-loaded polylactide (PLA) microspheres (PPMSs) were prepared by a modified double-emulsion-solvent evaporation method. In addition, PPMSs and cisplatin (DDP) were co-embedded in a thermosensitive hydrogel to construct a dual-drug co-delivery hydrogel system (PPMSs/DDP@Gel) for in-situ chemotherapy to treat melanoma by means of an intra-tumoral injection. The system allows for the sustained release of two drugs and exhibits good temperature-sensitive properties. In vitro antitumor activity showed that this hydrogel composite can induce B16 cell apoptosis and inhibit its migration. In vivo, anti-tumor studies have shown that the PPMSs/DDP@Gel significantly inhibited tumor growth, prolonged the survival of tumor-bearing mice, and had no obvious toxic side effects on major organs. Furthermore, immunohistochemical analysis revealed that PPMSs/DDP@Gel significantly inhibited tumor cell proliferation and promoted apoptosis of tumor cells. Taken together, the injectable temperature-sensitive PPMSs/DDP@Gel is a promising candidate for the local treatment of melanoma.