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1.
Adv Mater ; : e2403908, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38828745

RESUMO

The development of high-performance polymer is crucial for the fabrication of triboelectric nanogenerators (TENGs) used in extreme conditions. Liquid crystal polyarylate thermosets (LCTs) demonstrate great potential as triboelectric material by virtue of exceptional comprehensive properties. However, there are only a few specific end-groups like phenylethynyl matching the LCT polycondensation temperature (above 300 °C). Moreover, the excellent properties of LCTs rely on the crosslinked network formed with long curing time at high temperature, restricting their further application in triboelectric material. Herein, a fast-curing LCT is designed by terminating with 4-maleimidophenol possessing appropriate reactivity. The resultant LCT (MA-LC-MA) exhibits much lower polycondensation temperature (250-270 °C) and curing temperature of 300 °C within only 1 min compared to typical LCTs (cured at 370 °C for 1 h). Furthermore, the cured MA-LC-MA retains a high glass transition temperature of 135 °C, storage modulus of 6 MPa even at 350 °C, and great electrical output performance. Additionally, triboelectric measurement related to the dielectric properties that vary with crosslinked network is innovatively utilized as an analysis technique of curing progress. This work provides a new strategy to design high-performance TENGs and promotes the development of next generation thermosets in extreme conditions.

2.
ACS Nano ; 18(3): 2290-2301, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38207222

RESUMO

Anthocyanins with different structures have different anti-inflammatory and anti-cancer properties. Precise structural use can improve the chemopreventive effects of anthocyanins and enhance treatment outcomes because the anthocyanin structure influences its functional sites and activities. However, owing to the available variety of anthocyanins and their complex structures, the low matching of intermolecular forces between existing adsorbents and anthocyanins limits the targeted separation of anthocyanin monomers. Short-range and efficient selective binding, which is difficult to achieve, is the current focus in the extraction field. We here developed self-assembled Fe3O4-based nano adsorbers with different surface modifications based on adsorption-pairing synergy. The electrostatic force, coordination bond, hydrogen bond, and π-π* bond together induced selective adsorption between Fe3O4 nanoparticles and anthocyanin molecules. An acid-release solution disrupted the polarity balance in the aforementioned association system, thereby promoting the controlled release of anthocyanins. Among the candidates, the effects of morphology, particle size, surface charge, and functional group on adsorption performance were analyzed. The polyacrylamide-modified magnetic Fe3O4 nanoparticles were found to be favorable for selectively extracting anthocyanin, with an adsorption capacity of 19.74 ± 0.07 mg g-1. The release percentage of cyanidin-3-O-glucoside reached up to 98.6% ± 1.4%. This study offers a scientific basis for developing feasible nanotechniques to extract anthocyanins and plant active substances.


Assuntos
Antocianinas , Nanopartículas , Antocianinas/química , Preparações de Ação Retardada , Adsorção
3.
Sci Bull (Beijing) ; 69(12): 1875-1886, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38616151

RESUMO

There is usually a trade-off between high mechanical strength and dynamic self-healing because the mechanisms of these properties are mutually exclusive. Herein, we design and fabricate a fluorinated phenolic polyurethane (FPPU) elastomer based on octafluoro-4,4'-biphenol to overcome this challenge. This fluorine-based motif not only tunes interchain interactions through π-π stacking between aromatic rings and free-volume among polymer chains but also improves the reversibility of phenol-carbamate bonds via electron-withdrawing effect of fluorine atoms. The developed FPPU elastomer shows the highest recorded puncture energy (648.0 mJ), high tensile strength (27.0 MPa), as well as excellent self-healing efficiency (92.3%), along with low surface energy (50.9 MJ m-2), notch-insensitivity, and reprocessability compared with non-fluorinated counterpart biphenolic polyurethane (BPPU) elastomer. Taking advantage of the above-mentioned merits of FPPU elastomer, we prepare an anti-fouling triboelectric nanogenerator (TENG) with a self-healable, and reprocessable elastic substrate. Benefiting from stronger electron affinity of fluorine atoms than hydrogen atoms, this electronic device exhibits ultrahigh peak open-circuit voltage of 302.3 V compared to the TENG fabricated from BPPU elastomer. Furthermore, a healable and stretchable conductive composite is prepared. This research provides a distinct and general pathway toward constructing high-performance elastomers and will enable a series of new applications.

4.
Adv Mater ; 36(16): e2312500, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38215006

RESUMO

Polymers are playing important roles in the rapid development of triboelectric nanogenerators (TENGs); However, most polymers cannot meet the high requirements of thermomechanical performance; Thus, various polymeric composites are developed for triboelectric layer. These composites are hardly recycled since their reinforcements are unevenly distributed after reprocessing, which limits the sustainable development of TENGs. To solve the above challenges, in situ generated nanofiber reinforced composites (NFRCs) based on single-component liquid crystal polyarylate (LCP) are designed and prepared via a one-step polycondensation. Nonlinear naphthalene (NDA) widens the processing window of LCP without destabilizing the liquid crystal phase. The NDA-rich domains act as a matrix while the NDA-poor domains with higher rigidity form oriented nanofibers to achieve self-reinforcement. The resultant NFRCs possess high glass transition temperature (Tg > 220 °C) and storage modulus (E' = 0.1 GPa at 350 °C), which are far beyond existing triboelectric polymers, typically Tg < 110 °C and E' < 0.1 MPa (flowable) at 350 °C. Furthermore, NFRC-based TENG exhibits superior electrical output performance and retention rate (>90%) after reprocessing; Overall, this work offers a new design principle to prepare self-reinforced composites, which paves a way to explore high performance materials.

5.
Adv Mater ; 36(16): e2313761, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38211632

RESUMO

Soft robots have the potential to assist and complement human exploration of extreme and harsh environments (i.e., organic solvents). However, soft robots with stable performance in diverse organic solvents are not developed yet. In the current research, a non-Euclidean-plate under-liquid soft robot inspired by jellyfish based on phototropic liquid crystal elastomers is fabricated via a 4D-programmable strategy. Specifically, the robot employs a 3D-printed non-Euclidean-plate, designed with Archimedean orientation, which undergoes autonomous deformation to release internal stress when immersed in organic solvents. With the assistance of near-infrared light illumination, the organic solvent inside the robot vaporizes and generates propulsion in the form of bubble streams. The developed NEP-Jelly-inspired soft robot can swim with a high degree of freedom in various organic solvents, for example, N, N-dimethylformamide, N, N-dimethylacetamide, tetrahydrofuran, dichloromethane, and trichloromethane, which is not reported before. Besides bionic jellyfish, various aquatic invertebrate-inspired soft robots can potentially be prepared via a similar 4D-programmable strategy.

6.
Sci Adv ; 10(12): eadk5177, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38517961

RESUMO

The limited capacity of typical materials to resist stress loading, which affects their mechanical performance, is one of the most formidable challenges in materials science. Here, we propose a bone-inspired stress-gaining concept of converting typically destructive stress into a favorable factor to substantially enhance the mechanical properties of elastomers. The concept was realized by a molecular design of dynamic poly(oxime-urethanes) network with mesophase domains. During external loading, the mesophase domains in the condensed state were aligned into more ordered domains, and the dynamic oxime-urethane bonds served as the dynamic molecular locks disassociating and reorganizing to facilitate and fix the mesophase domains. Consequently, the tensile modulus and strength were enhanced by 1744 and 49.3 times after four cycles of mechanical training, respectively. This study creates a molecular concept with stress-gaining properties induced by repeated mechanical stress loading and will inspire a series of innovative materials for diverse applications.

7.
Polymers (Basel) ; 15(16)2023 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-37631451

RESUMO

Through the effective combination of photothermal conversion agent polydopamine (PDA) nanoparticles and epoxy acrylate polymer (EA), a new kind of near-infrared (NIR) light-triggered shape memory polymer (PDA/EA) is developed. Due to the outstanding photothermal effect of PDA, even with a very low concentration of PDA (0.1 wt.%), when exposed to an 808 nm NIR light with a power of 1 W/cm2, the temporary shapes can be fully light-responsive, recovered in 60 s. Based on dynamic thermomechanical analysis and thermal gravimetric analysis, it can be seen that the introduction of PDA is beneficial for improving dynamic mechanical properties and thermal resistance compared to EA. As an environmentally friendly and highly efficient photoactive SMP, PDA/EA has a great application prospect.

8.
Polymers (Basel) ; 15(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37447523

RESUMO

Bio-based polymers can reduce dependence on nonrenewable petrochemical resources and will be beneficial for future sustainable developments due to their low carbon footprint. In this work, the feasibility of bio-based polyamide 56 (PA56) substituting petroleum-based PA66 is systematically investigated. The crystallization, melting, and decomposition temperature of PA56 were all lower than that of PA66. PA56 formed a γ crystal type with larger grain size and took a longer amount of time to complete the crystallization process since its crystallization rate was lower than that of PA66. Compared with PA66, PA56 exhibited a higher tensile strength of 71.3 ± 1.9 MPa and specific strength of 64.8 ± 2.0 MPa but lower notched impact strength. More importantly, the limited oxygen index and vertical combustion measurement results indicated that the flame retardancy of PA56 was better than PA66, and the LOI values and the UL94 result of PA56 were 27.6% ± 0.9% and V-2. It is worth noting that the PA56 fiber had superior biodegradability compared to the PA66 fiber. PA56 showed significant biodegradation from the eighth week, whereas PA66 remained clean until the sixteenth week (without obvious biodegradation taking place). Eventually, PA56 did not show significant differences compared to PA66 in terms of thermal and mechanical properties. However, PA56 had great advantages in flame retardancy and biodegradability, indicating that the bio-based PA56 could potentially replace petroleum-based PA66 in many fields.

9.
Adv Mater ; 34(34): e2204543, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35896884

RESUMO

Flammability is a great challenge in the fields of electronics. The emergence of triboelectric nanogenerators (TENGs) provides a safe way to harvest environmentalally friendly energy and convert it into more secure power sources. Especially, polymer-based TENGs significantly accelerate the practical application of self-powered flexible electronics. However, most of the existing polymeric materials for TENGs are easily flammable and melt, dripping, in a fire scenario, and cannot be reused after combustion, which greatly limits the application of TENGs under extreme conditions. Herein, a fire-resistant TENG based on all-aromatic liquid crystalline poly(aryl ether ester) (LCPAEE ) synthesized via simple and efficient one-pot melt polycondensation is reported. The highly rigid main chain of LCPAEE endows the LCP-TENG with outstanding anti-dripping, temperature- and fire-resistance. The resultant LCP-TENG exhibits excellent electrical output performance, which is attributed to the high dielectric constant (ε' = 4.8) and fibrous-structured morphology of LCPAEE . The device can maintain over 65% of open-circuit voltage even after 16 s combustion (≈520 °C). Consequently, this work offers a novel strategy for tailoring the TENGs toward a secure power generator and electronics with fire hazard reduction, and potential application in firefighting, personal protection, and other extreme temperature environments.

10.
Sci Total Environ ; 830: 154545, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35304147

RESUMO

Multifunctional hydrogels with excellent comprehensive performance are essential prerequisite for the implementation of effective water resources technology with high efficiency and low energy consumption. Inspired by the water purification and self-healing properties of natural plants, and based on the synergy of photothermal and biological effects, high photothermal Fe3O4 nanoparticles and natural polyhydroxy oligomeric proanthocyanidin (OPC) are introduced into a water-active polyvinyl alcohol (PVA) hydrogel. Two new bio-hydrogels of PVA/Fe3O4/graphite and PVA/OPC with self-healing and stretchable properties are proposed and designed. The obtained hydrogels exhibit reversible covalent cross-linked water-promoted healing (chemically) and photothermal melting/recrystallization healing (physically). The double-layered hydrogel composite demonstrates a dual response function (sunlight and near-infrared light), along with water purification properties. It is prepared through a water spray triggered self-healing process. The ultimate fracture strain of the photothermal layer and purification layer hydrogel was more than 1000% and 400% respectively after self-healing.After 48 h of hydrogel composite adsorption, the color of a methylene blue solution faded, and the absorption peak at 664 nm decreased. In addition, this research adopts a phased evaporation method to concentrate local energy and provide power for seawater evaporation. The evaporation efficiency of seawater induced by near-infrared (NIR) light was up to 3.15 kg m-2 h-1, whereas that under sunlight was 1.25 kg m-2 h-1. Selection of the evaporation excitation light source allowed control of the evaporation efficiency. The proposed technology is expected to be widely applicable to the staged evaporation of seawater as well as water purification.


Assuntos
Chenopodiaceae , Nanoestruturas , Hidrogéis/química , Água do Mar , Luz Solar , Água
11.
ACS Nano ; 16(11): 19393-19402, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36367434

RESUMO

Soft robotics locomotion at the liquid-air interface has become more and more important for an intelligent society. However, existing locomotion of soft robotics is limited to two dimensions. It remains a formidable challenge to realize three-dimensional locomotion (X, Y, and Z axes) at the liquid-air two-phase interface due to the unbalanced mechanical environment. Inspired by meniscus-climbing beetle larva Pyrrhalta, the mechanism of a three-phase (liquid-solid-air) contact line is here proposed to address the aforementioned challenge. A corresponding 3D printed fully soft robotics (named larvobot) based on photoresponsive liquid crystal elastomer/carbon nanotubes composites endowed repeatable programmable deformation and high degree-of-freedom locomotion. Three-dimensional locomotion at the liquid-air interface including twisting and rolling-up has been developed. The equation of motion is established by analyzing the mechanics along the solid-water surface of the larvobot. Meanwhile, ANSYS is used to calculate the stress distribution, which coincides with the speculation. Moreover, soft robotics is remotely driven by light in a precise spatiotemporal control, which provides a great advantage for applications. As an example, we demonstrate the controllable locomotion of the soft robotics inside closed tubes, which could be used for drug delivery and intelligent transportation.


Assuntos
Menisco , Nanotubos de Carbono , Robótica , Locomoção , Impressão Tridimensional
12.
ACS Nano ; 16(10): 16954-16965, 2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-36125071

RESUMO

Self-powered information encoding devices (IEDs) have drawn considerable interest owing to their capability to process information without batteries. Next-generation IEDs should be reprogrammable, self-healing, and wearable to satisfy the emerging requirements for multifunctional IEDs; however, such devices have not been demonstrated. Herein, an integrated triboelectric nanogenerator-based IED with the aforementioned features was developed based on the designed light-responsive high-permittivity poly(sebacoyl diglyceride-co-4,4'-azodibenzoyl diglyceride) elastomer (PSeDAE) with a triple-shape-memory effect. The electrical memory feature was achieved through a microscale shape-memory property, enabling spatiotemporal information reprogramming for the IED. Macroscale shape-memory behavior afforded the IED shape-reprogramming ability, yielding wearable and detachable features. The dynamic transesterifications and light-heating groups in the PSeDAE afforded a remotely controlled rearrangement of its cross-linking network, producing the self-healing IED.


Assuntos
Elastômeros , Dispositivos Eletrônicos Vestíveis , Diglicerídeos , Fontes de Energia Elétrica
13.
Natl Sci Rev ; 8(5): nwaa154, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34691631

RESUMO

Elastomers are essential for stretchable electronics, which have become more and more important in bio-integrated devices. To ensure high compliance with the application environment, elastomers are expected to resist, and even self-repair, mechanical damage, while being friendly to the human body. Herein, inspired by peptidoglycan, we designed the first room-temperature autonomous self-healing biodegradable and biocompatible elastomers, poly(sebacoyl 1,6-hexamethylenedicarbamate diglyceride) (PSeHCD) elastomers. The unique structure including alternating ester-urethane moieties and bionic hybrid crosslinking endowed PSeHCD elastomers superior properties including ultrafast self-healing, tunable biomimetic mechanical properties, facile reprocessability, as well as good biocompatibility and biodegradability. The potential of the PSeHCD elastomers was demonstrated as a super-fast self-healing stretchable conductor (21 s) and motion sensor (2 min). This work provides a new design and synthetic principle of elastomers for applications in bio-integrated electronics.

14.
ACS Omega ; 6(13): 9129-9140, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33842782

RESUMO

In this study, using molybdenum sulfide (MoS2) as laser-sensitive particles and poly(propylene) (PP) as the matrix resin, laser-markable PP/MoS2 composite materials with different MoS2 contents ranging from 0.005 to 0.2% were prepared by melt-blending. A comprehensive analysis of the laser marking performance of PP/MoS2 composites was carried out by controlling the content of laser additives, laser current intensity, and the scanning speed of laser marking. The color difference test shows that the best laser marking performance of the composite can be obtained at the MoS2 content of 0.02 wt %. The surface morphology of the PP/MoS2 composite material was observed after laser marking using a metallographic microscope, an optical microscope, and a scanning electron microscope (SEM). During the laser marking process, the laser energy was absorbed and converted into heat energy to cause high-temperature melting, pyrolysis, and carbonization of PP on the surface of the PP/MoS2 composite material. The black marking from carbonized materials was formed in contrast to the white matrix. Using X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, and Raman spectroscopy, the composite materials before and after laser marking were tested and characterized. The PP/MoS2 composite material was pyrolyzed to form amorphous carbonized materials. The effect of the laser-sensitive MoS2 additive on the mechanical properties of composite materials was investigated. The results show that the PP/MoS2 composite has the best laser marking property when the MoS2 loading content is 0.02 wt %, the laser marking current intensity is 11 A, and the laser marking speed is 800 mm/s, leading to a clear and high-contrast marking pattern.

15.
Nat Commun ; 12(1): 4395, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34285224

RESUMO

The unique properties of self-healing materials hold great potential in the field of biomedical engineering. Although previous studies have focused on the design and synthesis of self-healing materials, their application in in vivo settings remains limited. Here, we design a series of biodegradable and biocompatible self-healing elastomers (SHEs) with tunable mechanical properties, and apply them to various disease models in vivo, in order to test their reparative potential in multiple tissues and at physiological conditions. We validate the effectiveness of SHEs as promising therapies for aortic aneurysm, nerve coaptation and bone immobilization in three animal models. The data presented here support the translation potential of SHEs in diverse settings, and pave the way for the development of self-healing materials in clinical contexts.


Assuntos
Implantes Absorvíveis , Materiais Biocompatíveis/uso terapêutico , Engenharia Biomédica , Poliuretanos/uso terapêutico , Animais , Aneurisma Aórtico/cirurgia , Materiais Biocompatíveis/química , Modelos Animais de Doenças , Elastômeros/química , Fixação de Fratura/métodos , Fraturas Ósseas/cirurgia , Humanos , Masculino , Teste de Materiais , Camundongos , Transferência de Nervo/métodos , Traumatismos dos Nervos Periféricos/cirurgia , Poliuretanos/química , Ratos , Suínos , Porco Miniatura
16.
RSC Adv ; 10(55): 33205-33212, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-35547632

RESUMO

The existence of pre- and post-reaction complexes has been proposed to influence hydrogen abstraction reaction kinetics, but the significance still remains controversial. A theoretical study is presented to discuss the effects of complexes on hydrogen abstraction from 2-butanone by OH radicals based on the detailed PESs at the DLPNO-CCSD(T)/aug-cc-pVTZ//M06-2x-D3/may-cc-pVTZ level with five pre-reaction complexes at the entrance of the channels and four post-reaction complexes at the exit. The hydrogen bond interactions, steric effects, and contributions to the bonding orbital of the OH radical species and 2-butanone species in the complex structures were visualized and investigated by wavefunction analyses. Three kinds of mechanisms-the general bimolecular reaction, the reaction with the complexes considered, and the well-skipping reaction-were compared based on high-pressure-limit rate constants, predicted branching ratios, and fractional populations of reactants and products in the temperature range of 250-2000 K. The existence of complexes was proved to be crucial in the kinetics and mechanisms of the hydrogen abstraction from 2-butanone molecules by OH radicals.

17.
Bioact Mater ; 5(4): 798-807, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32637744

RESUMO

The diversity of biomedical applications makes stereolithographic (SL) three-dimensional (3D) printing process complex. A strategy was developed to simulate the layer-by-layer fabrication of 3D printed products combining polymerization kinetic with reaction conditions to realize print preview. As a representative example, the typical UV-curable dental materials based on epoxy acrylate and photoinitiator with different molar ratios was exposed under varying intensity of UV light to verify the simulation results. A theoretical kinetics model containing oxygen inhibition was established. In-situ FTIR was employed to measure propagation and termination constants while coupled UV/vis was performed to examine the law of light attenuation during cure reaction, even with various colours and additives. Simulation results showed that the correlation coefficient square between the experiments and simulations of epoxy acrylate with 1%, 2% and 3% initiator upon 20 mW/cm2 UV light are 0.8959, 0.9324 and 0.9337, respectively. Consequently, our simulation of photopolymerization for SL 3D printing successfully realized visualization of printing quality before practically printing the targeted biomedical objects with complex topology structures.

18.
Adv Mater ; 32(8): e1906994, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31957099

RESUMO

Stretchable conductive fibers are key elements for next-generation flexible electronics. Most existing conductive fibers are electron-based, opaque, relatively rigid, and show a significant increase in resistance during stretching. Accordingly, soft, stretchable, and transparent ion-conductive hydrogel fibers have attracted significant attention. However, hydrogel fibers are difficult to manufacture and easy to dry and freeze, which significantly hinders their wide range of applications. Herein, organohydrogel fibers are designed to address these challenges. First, a newly designed hybrid crosslinking strategy continuously wet-spins hydrogel fibers, which are transformed into organohydrogel fibers by simple solvent replacement. The organohydrogel fibers show excellent antifreezing (< -80 °C) capability, stability (>5 months), transparency, and stretchability. The predominantly covalently crosslinked network ensures the fibers have a high dynamic mechanical stability with negligible hysteresis and creep, from which previous conductive fibers usually suffer. Accordingly, strain sensors made from the organohydrogel fibers accurately capture high-frequency (4 Hz) and high-speed (24 cm s-1 ) motion and exhibit little drift for 1000 stretch-release cycles, and are powerful for detecting rapid cyclic motions such as engine valves and are difficult to reach by previously reported conductive fibers. The organohydrogel fibers also demonstrate potential as wearable anisotropic sensors, data gloves, soft electrodes, and optical fibers.

19.
Acta Biomater ; 105: 97-110, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31953195

RESUMO

Cartilage defect repair remains a great clinical challenge due to the limited self-regeneration capacity of cartilage tissue. Surgical treatment of injured cartilage is rather difficult due to the narrow space in the articular cavity and irregular defect area. Herein, we designed and fabricated chondrogenic and physiological-temperature-triggered shape-memory ternary scaffolds for cell-free cartilage repair, where the poly (glycerol sebacate) (PGS) networks ensured elasticity and shape recovery, crystallized poly (1,3-propylene sebacate) (PPS) acted as switchable phase, and immobilized bioactive kartogenin (KGN) endowed the scaffolds with chondrogenic capacity. The resultant scaffolds exhibited shape-memory properties with shape-memory fixed ratio of 98% and recovered ratio of 97% at 37°C for PPS/PGS/KGN-100, indicating a good potential for minimally invasive implantation. The scaffolds gradually degraded in Dulbecco's phosphate-buffered saline and released KGN up to 12 weeks in vitro. In addition, the scaffolds promoted chondrogenic differentiation while inhibiting osteogenic differentiation of bone marrow-derived mesenchymal stem cells in a concentration-dependent manner and cartilage regeneration in full-thickness defects of rat femoropatellar groove for 12 weeks. Consequently, the PPS/PGS/KGN-100 scaffolds stimulated the formation of an overlying layer of neocartilage mimicking the characteristic architecture of native articular cartilage even in the absence of exogenous growth factors and seeded cells. This study provides much inspiration for future research on cartilage tissue engineering. STATEMENT OF SIGNIFICANCE: There are two crucial challenges for cartilage defect repair: the lack of self-regeneration capacity of cartilage tissue and difficult scaffold implantation via traditional open surgery due to space-limited joints. Herein, bioactive body-temperature-responsive shape memory scaffolds are designed to simultaneously address the challenges. The scaffolds can be readily implanted by minimally invasive approach and recover by body-temperature of patient. The integration of kartogenin endows scaffolds the bioactivity, leading to the first example of bulk shape-memory scaffolds for cell-free cartilage repair. These characteristics make the scaffolds advantageous for clinical translation. Moreover, our developed material is easy to be functionalized due to the presence of extensive free hydroxyl groups and provides a versatile platform to design diverse functional shape memory biomaterials.


Assuntos
Cartilagem Articular/fisiologia , Condrogênese , Regeneração/efeitos dos fármacos , Materiais Inteligentes/farmacologia , Alicerces Teciduais/química , Anilidas/química , Anilidas/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Condrogênese/efeitos dos fármacos , Decanoatos/química , Decanoatos/farmacologia , Preparações de Ação Retardada/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Glicerol/análogos & derivados , Glicerol/química , Glicerol/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Ácidos Ftálicos/química , Ácidos Ftálicos/farmacologia , Polímeros/química , Polímeros/farmacologia , Ratos Sprague-Dawley , Temperatura
20.
Nat Commun ; 11(1): 1107, 2020 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-32107380

RESUMO

The bio-integrated electronics industry is booming and becoming more integrated with biological tissues. To successfully integrate with the soft tissues of the body (eg. skin), the material must possess many of the same properties including compliance, toughness, elasticity, and tear resistance. In this work, we prepare mechanically and biologically skin-like materials (PSeD-U elastomers) by designing a unique physical and covalent hybrid crosslinking structure. The introduction of an optimal amount of hydrogen bonds significantly strengthens the resultant elastomers with 11 times the toughness and 3 times the strength of covalent crosslinked PSeD elastomers, while maintaining a low modulus. Besides, the PSeD-U elastomers show nonlinear mechanical behavior similar to skins. Furthermore, PSeD-U elastomers demonstrate the cytocompatibility and biodegradability to achieve better integration with tissues. Finally, piezocapacitive pressure sensors are fabricated with high pressure sensitivity and rapid response to demonstrate the potential use of PSeD-U elastomers in bio-integrated electronics.


Assuntos
Materiais Biomiméticos/química , Elastômeros/química , Equipamentos e Provisões Elétricas , Biomimética/métodos , Reagentes de Ligações Cruzadas/química , Elasticidade , Isocianatos/química , Teste de Materiais , Espectroscopia de Prótons por Ressonância Magnética , Pirimidinonas/química , Fenômenos Fisiológicos da Pele
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