Academic literature on the topic 'Interface hydrogel'

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Journal articles on the topic "Interface hydrogel"

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He, Chubin, Xiuru Xu, Yang Lin, Yang Cui, and Zhengchun Peng. "A Bilayer Skin-Inspired Hydrogel with Strong Bonding Interface." Nanomaterials 12, no. 7 (March 29, 2022): 1137. http://dx.doi.org/10.3390/nano12071137.

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Conductive hydrogels are widely used in sports monitoring, healthcare, energy storage, and other fields, due to their excellent physical and chemical properties. However, synthesizing a hydrogel with synergistically good mechanical and electrical properties is still challenging. Current fabrication strategies are mainly focused on the polymerization of hydrogels with a single component, with less emphasis on combining and matching different conductive hydrogels. Inspired by the gradient modulus structures of the human skin, we propose a bilayer structure of conductive hydrogels, composed of a spray-coated poly(3,4-dihydrothieno-1,4-dioxin): poly(styrene sulfonate) (PEDOT:PSS) as the bonding interface, a relatively low modulus hydrogel on the top, and a relatively high modulus hydrogel on the bottom. The spray-coated PEDOT:PSS constructs an interlocking interface between the top and bottom hydrogels. Compared to the single layer counterparts, both the mechanical and electrical properties were significantly improved. The as-prepared hydrogel showed outstanding stretchability (1763.85 ± 161.66%), quite high toughness (9.27 ± 0.49 MJ/m3), good tensile strength (0.92 ± 0.08 MPa), and decent elastic modulus (69.16 ± 8.02 kPa). A stretchable strain sensor based on the proposed hydrogel shows good conductivity (1.76 S/m), high sensitivity (a maximum gauge factor of 18.14), and a wide response range (0–1869%). Benefitting from the modulus matching between the two layers of the hydrogels, the interfacial interlocking network, and the patch effect of the PEDOT:PSS, the strain sensor exhibits excellent interface robustness with stable performance (>12,500 cycles). These results indicate that the proposed bilayer conductive hydrogel is a promising material for stretchable electronics, soft robots, and next-generation wearables.
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Lim, Chanhyuk, Yongseok Joseph Hong, Jaebong Jung, Yoonsoo Shin, Sung-Hyuk Sunwoo, Seungmin Baik, Ok Kyu Park, et al. "Tissue-like skin-device interface for wearable bioelectronics by using ultrasoft, mass-permeable, and low-impedance hydrogels." Science Advances 7, no. 19 (May 2021): eabd3716. http://dx.doi.org/10.1126/sciadv.abd3716.

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Hydrogels consist of a cross-linked porous polymer network and water molecules occupying the interspace between the polymer chains. Therefore, hydrogels are soft and moisturized, with mechanical structures and physical properties similar to those of human tissue. Such hydrogels have a potential to turn the microscale gap between wearable devices and human skin into a tissue-like space. Here, we present material and device strategies to form a tissue-like, quasi-solid interface between wearable bioelectronics and human skin. The key material is an ultrathin type of functionalized hydrogel that shows unusual features of high mass-permeability and low impedance. The functionalized hydrogel acted as a liquid electrolyte on the skin and formed an extremely conformal and low-impedance interface for wearable electrochemical biosensors and electrical stimulators. Furthermore, its porous structure and ultrathin thickness facilitated the efficient transport of target molecules through the interface. Therefore, this functionalized hydrogel can maximize the performance of various wearable bioelectronics.
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Michel, Raphaël, Léna Poirier, Quentin van Poelvoorde, Josette Legagneux, Mathieu Manassero, and Laurent Corté. "Interfacial fluid transport is a key to hydrogel bioadhesion." Proceedings of the National Academy of Sciences 116, no. 3 (January 2, 2019): 738–43. http://dx.doi.org/10.1073/pnas.1813208116.

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Attaching hydrogels to soft internal tissues is a key to the development of a number of biomedical devices. Nevertheless, the wet nature of hydrogels and tissues renders this adhesion most difficult to achieve and control. Here, we show that the transport of fluids across hydrogel−tissue interfaces plays a central role in adhesion. Using ex vivo peeling experiments on porcine liver, we characterized the adhesion between model hydrogel membranes and the liver capsule and parenchyma. By varying the contact time, the tissue hydration, and the swelling ratio of the hydrogel membrane, a transition between two peeling regimes is found: a lubricated regime where a liquid layer wets the interface, yielding low adhesion energies (0.1 J/m2 to 1 J/m2), and an adhesive regime with a solid binding between hydrogel and tissues and higher adhesion energies (1 J/m2 to 10 J/m2). We show that this transition corresponds to a draining of the interface inducing a local dehydration of the tissues, which become intrinsically adhesive. A simple model taking into account the microanatomy of tissues captures the transition for both the liver capsule and parenchyma. In vivo experiments demonstrate that this effect still holds on actively hydrated tissues like the liver capsule and show that adhesion can be strongly enhanced when using superabsorbent hydrogel meshes. These results shed light on the design of predictive bioadhesion tests as well as on the development of improved bioadhesive strategies exploiting interfacial fluid transport.
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Zhao, Wenyu, Zhuofan Lin, Xiaopu Wang, Ziya Wang, and Zhenglong Sun. "Mechanically Interlocked Hydrogel–Elastomer Strain Sensor with Robust Interface and Enhanced Water—Retention Capacity." Gels 8, no. 10 (September 30, 2022): 625. http://dx.doi.org/10.3390/gels8100625.

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Hydrogels are stretchable ion conductors that can be used as strain sensors by transmitting strain-dependent electrical signals. However, hydrogels are susceptible to dehydration in the air, leading to a loss of flexibility and functions. Here, a simple and general strategy for encapsulating hydrogel with hydrophobic elastomer is proposed to realize excellent water-retention capacity. Elastomers, such as polydimethylsiloxanes (PDMS), whose hydrophobicity and dense crosslinking network can act as a barrier against water evaporation (lost 4.6 wt.% ± 0.57 in 24 h, 28 °C, and ≈30% humidity). To achieve strong adhesion between the hydrogel and elastomer, a porous structured thermoplastic polyurethane (TPU) is used at the hydrogel-elastomer interface to interlock the hydrogel and bond the elastomer simultaneously (the maximum interfacial toughness is over 1200 J/m2). In addition, a PDMS encapsulated ionic hydrogel strain sensor is proposed, demonstrating an excellent water-retention ability, superior mechanical performance, highly linear sensitivity (gauge factor = 2.21, at 100% strain), and robust interface. Various human motions were monitored, proving the effectiveness and practicability of the hydrogel-elastomer hybrid.
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Chen, Jing, Jingli Yang, Guorong Gao, and Jun Fu. "Responsive Bilayered Hydrogel Actuators Assembled by Supramolecular Recognition." MRS Advances 3, no. 28 (2018): 1583–88. http://dx.doi.org/10.1557/adv.2018.222.

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ABSTRACTMacroscopic assembling of responsive hydrogels has been used to construct soft actuators that transform their shape upon external stimuli. It remains a challenge to establish a robust assembling interface between gels. Here, we demonstrate a fabrication of bilayered hydrogel actuators assembled by host-guest recognition at the interface. The supramolecular recognition enabled efficient, rapid, and robust macroscopic assembling of hydrogels, which was utilized to create gel bilayers that were actuated upon unbalanced swelling/deswelling.
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Shay, Tim, Orlin D. Velev, and Michael D. Dickey. "Soft electrodes combining hydrogel and liquid metal." Soft Matter 14, no. 17 (2018): 3296–303. http://dx.doi.org/10.1039/c8sm00337h.

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Liquid metals interfaced with hydrogels create soft, deformable electrodes for emerging wearable devices and soft robotics. This paper quantifies and tunes the impedance of this interface for use in ECG electrodes.
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Zhao, Xinyi, Bilal Javed, Furong Tian, and Kangze Liu. "Hydrogel on a Smart Nanomaterial Interface to Carry Therapeutics for Digitalized Glioma Treatment." Gels 8, no. 10 (October 17, 2022): 664. http://dx.doi.org/10.3390/gels8100664.

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Glioma is considered the primary brain tumor to cause brain illnesses, and it is difficult to treat and shows resistance to various routine therapeutics. The most common treatments to cure glioma are the surgical removal of tumors followed by adjuvant chemotherapy and radiation therapy. The latest biocompatible interfaces have been incorporated into therapeutic modalities such as the targeted delivery of drugs using hydrogels to treat and manage brain glioma. This review illustrates the applications of the multimodal hydrogel as the carrier of therapeutics, gene therapy, therapeutic tactics, and glioma devices. The scientific articles were retrieved from 2019 to 2022 on Google Scholar and the Scopus database and screened to determine whether they were suitable for review. The 20 articles that fit the study are summarized in this review. These studies indicated that the sizes of the hydrogel range from 28 nm to 500 nm. There are 16 out of 20 articles that also explain the post-surgical application of hydrogels, and 13 out of 20 articles are employed in 3D culture and other structural manifestations of hydrogels. The pros of the hydrogel include the quick formulation for a sufficient filling of irregular damage sites, solubilizing hydrophobic drugs, continuously slowing drug release, provision of a 3D cell growth environment, improving efficacy, targetability of soluble biomolecules, increasing patient compliance, and decreased side effects. The cons of the hydrogel include difficult real-time monitoring, genetic manipulations, the cumbersome synchronized release of components, and lack of safety data. The prospects of the hydrogel may include the development of electronic hydrogel sensors that can be used to enhance guidance for the precise targeting patterns using patient-specific pathological idiosyncrasies. This technology has the potential to revolutionize the precision medicine approaches that would aid in the early detection and management of solid brain tumors.
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Lin, Yue-Xian, Shu-Han Li, and Wei-Chen Huang. "Fabrication of Soft Tissue Scaffold-Mimicked Microelectrode Arrays Using Enzyme-Mediated Transfer Printing." Micromachines 12, no. 9 (August 31, 2021): 1057. http://dx.doi.org/10.3390/mi12091057.

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Hydrogels are the ideal materials in the development of implanted bioactive neural interfaces because of the nerve tissue-mimicked physical and biological properties that can enhance neural interfacing compatibility. However, the integration of hydrogels and rigid/dehydrated electronic microstructure is challenging due to the non-reliable interfacial bonding, whereas hydrogels are not compatible with most conditions required for the micromachined fabrication process. Herein, we propose a new enzyme-mediated transfer printing process to design an adhesive biological hydrogel neural interface. The donor substrate was fabricated via photo-crosslinking of gelatin methacryloyl (GelMA) containing various conductive nanoparticles (NPs), including Ag nanowires (NWs), Pt NWs, and PEDOT:PSS, to form a stretchable conductive bioelectrode, called NP-doped GelMA. On the other hand, a receiver substrate composed of microbial transglutaminase-incorporated gelatin (mTG-Gln) enabled simultaneous temporally controlled gelation and covalent bond-enhanced adhesion to achieve one-step transfer printing of the prefabricated NP-doped GelMA features. The integrated hydrogel microelectrode arrays (MEA) were adhesive, and mechanically/structurally bio-compliant with stable conductivity. The devices were structurally stable in moisture to support the growth of neuronal cells. Despite that the introduction of AgNW and PEDOT:PSS NPs in the hydrogels needed further study to avoid cell toxicity, the PtNW-doped GelMA exhibited a comparable live cell density. This Gln-based MEA is expected to be the next-generation bioactive neural interface.
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Gevrek, Tugce Nihal, Aysun Degirmenci, Rana Sanyal, and Amitav Sanyal. "Multifunctional and Transformable ‘Clickable’ Hydrogel Coatings on Titanium Surfaces: From Protein Immobilization to Cellular Attachment." Polymers 12, no. 6 (May 26, 2020): 1211. http://dx.doi.org/10.3390/polym12061211.

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Multifunctionalizable hydrogel coatings on titanium interfaces are useful in a wide range of biomedical applications utilizing titanium-based materials. In this study, furan-protected maleimide groups containing multi-clickable biocompatible hydrogel layers are fabricated on a titanium surface. Upon thermal treatment, the masked maleimide groups within the hydrogel are converted to thiol-reactive maleimide groups. The thiol-reactive maleimide group allows facile functionalization of these hydrogels through the thiol-maleimide nucleophilic addition and Diels–Alder cycloaddition reactions, under mild conditions. Additionally, the strained alkene unit in the furan-protected maleimide moiety undergoes radical thiol-ene reaction, as well as the inverse-electron-demand Diels–Alder reaction with tetrazine containing molecules. Taking advantage of photo-initiated thiol-ene ‘click’ reactions, we demonstrate spatially controlled immobilization of the fluorescent dye thiol-containing boron dipyrromethene (BODIPY-SH). Lastly, we establish that the extent of functionalization on hydrogels can be controlled by attachment of biotin-benzyl-tetrazine, followed by immobilization of TRITC-labelled ExtrAvidin. Being versatile and practical, we believe that the described multifunctional and transformable ‘clickable’ hydrogels on titanium-based substrates described here can find applications in areas involving modification of the interface with bioactive entities.
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Qiu, Fei, Xiaopeng Fan, Wen Chen, Chunming Xu, Yumei Li, and Renjian Xie. "Recent Progress in Hydrogel-Based Synthetic Cartilage: Focus on Lubrication and Load-Bearing Capacities." Gels 9, no. 2 (February 8, 2023): 144. http://dx.doi.org/10.3390/gels9020144.

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Articular cartilage (AC), which covers the ends of bones in joints, particularly the knee joints, provides a robust interface to maintain frictionless movement during daily life due to its remarkable lubricating and load-bearing capacities. However, osteoarthritis (OA), characterized by the progressive degradation of AC, compromises the properties of AC and thus leads to frayed and rough interfaces between the bones, which subsequently accelerates the progression of OA. Hydrogels, composed of highly hydrated and interconnected polymer chains, are potential candidates for AC replacement due to their physical and chemical properties being similar to those of AC. In this review, we summarize the recent progress of hydrogel-based synthetic cartilage, or cartilage-like hydrogels, with a particular focus on their lubrication and load-bearing properties. The different formulations, current limitations, and challenges of such hydrogels are also discussed. Moreover, we discuss the future directions of hydrogel-based synthetic cartilage to repair and even regenerate the damaged AC.
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Dissertations / Theses on the topic "Interface hydrogel"

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Han, Ning. "Hydrogel-Electrospun Fiber Mat Composite Materials for the Neuroprosthetic Interface." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1292881087.

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Edgerton, Alexander James. "Design and Testing of a Hydrogel-Based Droplet Interface Lipid Bilayer Array System." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/56894.

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The research presented in this thesis includes the development of designs, materials, and fabrication processes and the results of characterization experiments for a meso-scale hydrogel-based lipid bilayer array system. Two design concepts are investigated as methods for forming Droplet Interface Bilayer (DIB) arrays. Both concepts use a base of patterned silver with Ag/AgCl electrodes patterned onto a flat polymer substrate. In one technique, photopolymerizable hydrogel is cured through a mask to form an array of individual hydrogels on top of the patterned electrodes. The other technique introduces a second type of polymer substrate that physically supports an array of hydrogels using a set of microchannels. This second substrate is fitted onto the first to contact the hydrogels to the electrodes. The hydrogels are used to support and shape droplets of water containing phospholipids, which self-assemble at the surface of the droplet when submerged in oil. Two opposing substrates can then be pushed together, and a bilayer will form at the point where each pair of monolayers come into contact. The photopatterning technique is used to produce small arrays of hydrogels on top of a simple electrode pattern. Systems utilizing the microchannel substrate are used to create mesoscale hydrogel arrays of up to 3x3 that maintained a low resistance (~50-150 kΩ) connection to the substrate. Up to three bilayers are formed simultaneously and verified through visual observation and by recording the current response behavior. Arrays of varying sizes and dimensions and with different electrode patterns can be produced quickly and inexpensively using basic laboratory techniques. The designs and fabrication processes for both types of arrays are created with an eye toward future development of similar systems at the microscale.
Master of Science
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Augustine, Anusree. "Swelling induced debonding of thin hydrogel films grafted on silicon substrate : the role of interface physical-chemistry." Electronic Thesis or Diss., Université Paris sciences et lettres, 2022. http://www.theses.fr/2022UPSLS040.

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Les revêtements d'hydrogel sont des réseaux de polymères transparents et hydrophiles capables d’abosrber plusieurs fois leur épaisseur en eau. Cependant, les contraintes induites par le gonflement du film peuvent entraîner un décollement préjudiciable de l'hydrogel ce qui peut limiter l’utilisation pratique des ces revêtements. Dans cette étude, nous proposons de décrire les mécanismes de décollement de films minces d’hydrogel en fonction de leur densité de greffage à l'interface film/substrat. Le but est de pouvoir contrôler et prédire la dégradation des revêtements hydrogel pendant le gonflement ou sous des contraintes de contact. Dans ce but, nous avons développé une méthodologie permettant de mesurer l'initiation et la propagation de la délamination induite par le gonflement de films minces d’hydrogel à partir de défauts d'interface préexistants bien contrôlés.Des films minces d'hydrogel de poly(diméthylacrylamide) (PDMA) attachés à la surface sont préparés sur des plaquettes de silicium à partir de la réticulation et du greffage simultanés (CLAG) de chaînes polymères fonctionnalisées par la chimie click thiol-ène. Cette stratégie permet de faire varier l'épaisseur du film (0.1 - 2 µm) et de contrôler le taux de gonflement du réseau, ici fixé à 2, tout en assurant une densité de réticulation homogène. Afin de faire varier la résistance de l'interface film/substrat, le substrat en silicium est greffé avec des mélanges de mercaptosilane (réactif) et de propylsilane (inerte) dans différentes proportions avant le dépôt du film mince. Alors que le mercaptosilane est capable de former des liaisons covalentes avec le réseau PDMA, le propylsilane ne réagit pas, ce qui permet de contrôler le taux de greffage du film mince d’hydrogel sur le substrat. Nous caractérisons la fraction de surface de mercaptosilane ainsi obtenue par des analyses XPS et TOF-SIMS. Par ailleurs, toujours à l’interface subtrat/film, des défauts linéaires bien contrôlés ayant une faible adhérence (largeur entre 10 et 100 µm) sont créés sur le substrat en passivant de façon localisée les groupes thiol réactifs par microlithographie. Ces défauts nucléent le décollement des films de façon bien localisée, ce qui permet ensuite de suivre la propagation de la décohésion à partir de ces défauts.Le décollement du film induit par le gonflement est réalisé sous un flux de vapeur constant assurant la saturation du film en eau. En observant le décollement progressif du film à partir des défauts linéaires préexistants, nous retrouvons un motif d’instabilité classique dit de fil de téléphone et nous montrons que le décollement résulte de contraintes de gonflement localisées proche de la ligne de décollement. Nous mesurons la vitesse de propagation du décollement dans la zone où le film est greffé sur le substrat et nous observons qu’elle augmente de deux ordres de grandeur lorsque la quantité de propylsilane dans le mélange de silanes réactifs passe de 0 à 90 %, c’est-à-dire lorsque le taux de greffage du film décroit. Un seuil d'épaisseur pour le décollement est également observé, les films pouvant se décoller étant d’autant plus minces que le taux de greffage du film ets faible. Les mesures de ce seuil sont discutées à partir d'un argument simple de mécanique de la rupture qui permet de rendre compte semi quantitativement de nos mesures
Hydrogel coatings are transparent and hydrophilic polymer networks that absorb a lot of water and can be suitable candidates for anti-mist coatings. However, swelling-induced stresses within the film can result in detrimental debonding of hydrogel and may fail. In this study, these debonding processes are investigated in the relation to the grafting density at the film/substrate interface, so as to control and predict the failure of the coatings during swelling or under contact stresses. For that purpose, we have developed a methodology consisting in monitoring the initiation and the propagation of swelling-induced delamination from well-controlled preexisting interface defects.Surface-attached poly(dimethylacrylamide) (PDMA) hydrogel thin films are prepared on silicon wafers from the simultaneous Cross-Linking And Grafting (CLAG) of functionalized polymer chains by thiol-ene click chemistry. This strategy allows to tune the film thickness (0.1-2 µm) while ensuring a homogeneous crosslinking density. In order to vary the strength of the film/substrate interface, the silicon wafer is grafted by mixing reactive mercaptosilane and unreactive propylsilane in various proportions prior to the formation of the hydrogel film. We characterize the mercaptosilane surface fraction thus obtained by XPS and TOF-SIMS analyses. Well-controlled line defects (width between 2 and 100 µm) are also created to nucleate delamination of the hydrogel from the substrate.Swelling-induced debonding of the film is achieved under a constant vapor flow ensuring water saturation. Optical observations show the progressive debonding of the film from the pre-existing line defects under the action of localized swelling stresses. We obtain a delamination pattern of typical so-called telephone cord instability. We measure the debonding propagation velocity where the hydrogel is grafted to the substrate. The debonding rate is found to decrease over two orders of magnitude when the amount of mercaptosilane in the reactive silane mixture is increased from 10% to 100% while increasing the covalent bonds between hydrogel and substrate. A threshold thickness for debonding is also observed. This threshold thickness increases with the amount of mercaptosilane used to graft the substrate. We derived quantitative values of the interface fracture energy from the measured thickness threshold with a simple fracture mechanics model
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Baxani, Kamal Divesh. "Hydrogel encapsulated droplet interface bilayer networks as a chassis for artificial cells and a platform for membrane studies." Thesis, Cardiff University, 2017. http://orca.cf.ac.uk/112707/.

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There has been increasing interest in droplet interface bilayers (DIBs) as novel devices for the study of lipid membranes and the development of artificial cell systems. Although DIBs have demonstrated to be useful in a number of laboratory applications, their wider use is hampered by a limited ability to exist untethered and remain mechanically stable beyond controlled laboratory environments. In this thesis, a microfluidic system is developed which enables the facile generation of hydrogel-encapsulated DIB networks which are freestanding and can exist in air, water and oil environments, without compromise to their ability to interface with the surrounding environment. Electrophysiology is employed in order to demonstrate the formation of bilayers between the encapsulated DIBs (eDIBs) and their external environment, achieved via the incorporation of the transmembrane pore α-Hemolysin. The eDIBs produced here are able to form higher-order structures akin to tissues via their assembly and adherence to one another, further demonstrating their potential to act as a chassis for artificial cells. Furthermore, the potential of eDIBs to be used as a platform for membrane studies is demonstrated via their use as a high-throughput array for membrane disruption fluorescence measurements using a plate reader, which makes use of the ability of eDIBs to be generated in large numbers as well as to be mechanically handled and placed in the wells of a 96-well plate. Fluorescence measurements were taken on up to 47 eDIBs simultaneously, and were able to detect bilayer leakage through pores as well as bilayer failure. The above experiments comprise the design, manufacture and use of a novel kind of DIB construct as a chassis for artificial cells and a platform for high-throughput membrane studies. It is proposed that eDIBs may help in realising the unfulfilled potential of DIB networks in applications in healthcare and beyond.
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Berts, Ida. "Relating the Bulk and Interface Structure of Hyaluronan to Physical Properties of Future Biomaterials." Doctoral thesis, Uppsala universitet, Institutionen för kemi - Ångström, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-198357.

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This dissertation describes a structural investigation of hyaluronan (HA) with neutron scattering techniques. HA is a natural biopolymer and one of the major components of the extracellular matrix, synovial fluid, and vitreous humor.  It is used in several biomedical applications like tissue engineering, drug delivery, and treatment of osteoarthritis. Although HA is extensively studied, very little is known about its three-dimensional conformation and how it interacts with ions and other molecules. The study aims to understand the bulk structure of a cross-linked HA hydrogel, as well as the conformational arrangement of HA at solid-liquid interfaces. In addition, the structural changes of HA are investigated by simulation of physiological environments, such as changes in ions, interactions with nanoparticles, and proteins etc. Small-angle neutron scattering and neutron reflectivity are the two main techniques applied to investigate the nanostructure of hyaluronan in its original, hydrated state. The present study on hydrogels shows that they possess inhomogeneous structures best described with two correlation lengths, one of the order of a few nanometers and the other in the order of few hundred nanometers. These gels are made up of dense polymer-rich clusters linked to each other. The polymer concentration and mixing governs the connectivity between these clusters, which in turn determines the viscoelastic properties of the gels. Surface-tethered HA at a solid-liquid interface is best described with a smooth varying density profile. The shape of this profile depends on the immobilization chemistry, the deposition protocol, and the ionic interactions. HA could be suitably modified to enhance adherence to metal surfaces, as well as incorporation of proteins like growth factors with tunable release properties. This could be exploited for surface coating of implants with bioactive molecules. The knowledge gained from this work would significantly help to develop future biomaterials and surface coatings of implants and biomedical devices.
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Vanderwerker, Zachary Thomas. "Using Lipid Bilayers in an Artificial Axon System." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/24449.

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Since the rise of multicellular organisms, nature has created a wide range of solutions for life on Earth. This diverse set of solutions presents a broad design space for a number of bio-inspired technologies in many different fields. Of particular interest for this work is the computational and processing power of neurons in the brain. Neuronal networks for transmitting and processing signals have advantages to their electronic counterparts in terms of power efficiency and the ability to handle component failure. In this thesis, an artificial axon system using droplet on hydrogel bilayers (DHBs) in conjunction with alamethicin channels was developed to show properties of action potential signal propagation that occur in myelinated nerve cells. The research demonstrates that the artificial axon system is capable of modifying signals that travel perpendicular to a lipid bilayer interface due to the voltage-gating properties of alamethicin within the connected bilayer. The system was used to show a signal boosting behavior similar to what occurs in the nodes of Ranvier of a myelinated axon. In addition, the artificial axon system was used to show that alamethicin channels within a lipid bilayer behave similarly to slow-acting potassium channels in a real axon in that they follow a sigmoid activation curve in response to a step potential change.
Master of Science
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Yang, Xianpeng. "Strong Cellulose Nanofiber Composite Hydrogels via Interface Tailoring." Kyoto University, 2020. http://hdl.handle.net/2433/253333.

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Ciapa, Lola. "Frottement de films minces d'hydrogel : poroélasticité et interface." Electronic Thesis or Diss., Université Paris sciences et lettres, 2022. http://www.theses.fr/2022UPSLS006.

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Les films minces d’hydrogel sont des systèmes prometteurs pour des applications en ingénierie biomédicale (cartilage articulaire synthétique, lentilles de contact) ou optique (revêtements anti-buée) grâce à leur biocompatibilité, leur transparence et leurs propriétés lubrifiantes. Les propriétés frictionnelles de ces systèmes dans l’eau, cruciales pour leur utilisation, sont complexes car elles mettent en jeu plusieurs mécanismes physiques souvent couplés. La lubrification par un film d’eau, les écoulements poroélastiques dans le gel sous l’effet de gradients de pression et les interactions moléculaires à l’interface entre le gel et la surface glissante sont évoqués pour expliquer le frottement des gels.Dans ce travail de thèse, nous avons mesuré puis décrit le rôle des interactions moléculaires interfaciales dans le frottement des hydrogels dans l’eau. Pour cela, nous avons développé un dispositif expérimental permettant de supprimer à la fois les contributions poroélastiques et de lubrification par un film d’eau. En faisant glisser une lentille sphérique de silice en rotation sur un film de gel de polydiméthylacrylamide d’épaisseur micrométrique immergé dans l’eau, sous force normale et vitesse imposées, nous mesurons les forces de frottement et nous observons le contact gel/silice par interférométrie. En fonctionnalisant la silice par des silanes variés, nous mettons en évidence un effet important de la chimie de surface de la lentille de silice sur les forces de frottement mesurées et leur dépendance en vitesse de glissement, laquelle est variée sur trois ordres de grandeur. En régime transitoire, nous mettons en évidence un phénomène de vieillissement de l’interface lorsque la lentille est maintenue en contact avec le gel sur des temps longs avant d’initier le glissement. Pour discuter ces observations, nous proposons un modèle de frottement en régime stationnaire basé sur l’adsorption/désorption thermodynamique des chaînes polymères sur la surface glissante. Ce modèle rend compte des observations expérimentales à partir de paramètres moléculaires en accord avec la physicochimie des silices silanisées
Thin hydrogel films find applications in biomedical engineering (synthetic articular cartilage, contact lenses) or optics (anti-fog coatings) thanks to their biocompatibility, transparency, and lubricating properties. The frictional properties of these systems in water, which are crucial for their use, arise from the complex coupling of several physical mechanisms. Fluid film lubrication, poroelastic flows in the gel due to pressure gradients, and molecular interactions at the interface between the gel and the sliding surface are all involved in gel friction.In the present work, we provide a description of the role played by interfacial molecular interactions on friction of hydrogels in water. To this end, we built an experimental set up in which both poroelastic flows and water film lubrication are suppressed. By sliding a spherical silica lens with a rotative trajectory over a micrometer-thick polydimethylacrylamide gel film immersed in water, under imposed normal force and velocity, we measure the frictional forces and observe the gel/silica contact by interferometry. By functionalizing the silica with various silanes, we show an effect of surface chemistry of the silica lens on the measured friction forces and their dependence on sliding speed, over three decades in velocity. In transient regime, we demonstrate an ageing phenomenon of the interface when the lens is maintained in contact with the gel over long times before sliding initiation. We derive a model for steady state friction based on the thermodynamic adsorption/desorption of polymer chains on the sliding surface. This model successfully accounts for our experimental observations with a set of molecular parameters which agree with the physico-chemistry of our silanated systems
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Feng, Shi. "Elucidation of hydrogen oxidation kinetics on metal/proton conductor interface." Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/48941.

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High temperature proton conducting perovskite oxides are very attractive materials for applications in electrochemical devices, such as solid oxide fuel cells (SOFCs) and hydrogen permeation membranes. A better understanding of the hydrogen oxidation mechanism over the metal/proton conductor interface, is critical for rational design to further enhance the performances of the applications. However, kinetic studies focused on the metal/proton system are limited, compared with the intensively studied metal/oxygen ion conductor system, e.g., Ni/YSZ (yttrium stabilized zirconia, Zr₁-ₓYₓO₂-δ). This work presents an elementary kinetic model developed to assess reaction pathway of hydrogen oxidation/reduction on metal/proton conductor interface. Individual rate expressions and overall hydrogen partial pressure dependencies of current density and polarization resistance were derived in different rate limiting cases. The model is testified by tailored experiments on Pt/BaZr₀.₁Ce₀.₇Y₀.₁Yb₀.₁O₃-δ (BZCYYb) interface using pattern electrodes. Comparison of electrochemical testing and the theoretical predictions indicates the dissociation of hydrogen is the rate-limiting step (RLS), instead of charge transfer, displaying behavior different from metal/oxygen ion conductor interfaces. The kinetic model presented in this thesis is validated by high quantitative agreement with experiments under various conditions. The discovery not only contributes to the fundamental understanding of the hydrogen oxidation kinetics over metal/proton conductors, but provides insights for rational design of hydrogen oxidation catalysts in a variety of electrochemical systems.
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Matsumoto, Mitsuhiro. "Molecular Orientation near Liquid-vapor Interface of Hydrogen-bonding Systems." 京都大学 (Kyoto University), 1988. http://hdl.handle.net/2433/86403.

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Books on the topic "Interface hydrogel"

1

M, Hasan M., Nyland T. W, and United States. National Aeronautics and Space Administration., eds. Mixing and transient interface condensation of a liquid hydrogen tank. [Washington, DC]: National Aeronautics and Space Administration, 1993.

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M, Hasan Mohammad, Nyland Ted W, and United States. National Aeronautics and Space Administration., eds. Mixing and transient interface condensation of a liquid hydrogen tank. [Washington, DC]: National Aeronautics and Space Administration, 1993.

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Gregory, Jerkiewicz, Feliu Juan M, Popov Branko N, Electrochemical Society Meeting, Electrochemical Society. Physical Electrochemistry Division., and International Symposium on Hydrogen Surfaces and Interfaces (2000 : Toronto, Ont.), eds. Hydrogen at surface and interfaces: Proceedings of the international symposium. Pennington, NJ: Electrochemical Society, Inc., 2000.

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H, Fabik Richard, and Lewis Research Center, eds. Using silicon diodes for detecting the liquid-vapor interface in hydrogen. Cleveland, Ohio: National Aeronautics and Space Administration, Lewis Research Center, 1992.

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Khatamian, D. Hydrogen traps in the oxide/alloy interface region of Zr-Nb alloys. Chalk River, Ont: Reactor Materials Research Branch, Chalk River Laboratories, 1995.

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National Aeronautics and Space Administration (NASA) Staff. Mixing and Transient Interface Condensation of a Liquid Hydrogen Tank. Independently Published, 2018.

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Surface and interface study of PdCr/SiC schottky diode gas sensor annealed at 425C̊. [Cleveland, Ohio]: National Aeronautics and Space Administration, Lewis Research Center, 1998.

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Lin, Nian, and Sebastian Stepanow. Designing low-dimensional nanostructures at surfaces by supramolecular chemistry. Edited by A. V. Narlikar and Y. Y. Fu. Oxford University Press, 2017. http://dx.doi.org/10.1093/oxfordhb/9780199533046.013.10.

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This article describes the use of supramolecular chemistry to design low-dimensional nanostructures at surfaces. In particular, it discusses the design strategies of two types of low-dimensional supramolecular nanostructures: structures stabilized by hydrogen bonds and structures stabilized by metal-ligand co-ordination interactions. After providing an overview of hydrogen-bond systems such as 0D discrete clusters, 1D chains, and 2D open networks and close-packed arrays, the article considers metal-co-ordination systems. It also presents experimental results showing that both hydrogen bonds and metal co-ordination offer protocols to achieve unique nanostructured systems on 2D surfaces or interfaces. Noting that the conventional 3D supramolecular self-assembly has generated a vast number of nanostructures revealing high complexity and functionality, the article suggests that 2D approaches can be applied to substrates with different symmetries as well as physical and chemical properties.
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Book chapters on the topic "Interface hydrogel"

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Matsumoto, Takuya. "Hydrogel-Based Biomimetic Environment for In Vitro Cell and Tissue Manipulation." In Interface Oral Health Science 2014, 161–68. Tokyo: Springer Japan, 2015. http://dx.doi.org/10.1007/978-4-431-55192-8_13.

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Roy, Niladri, Nabanita Saha, Takeshi Kitano, Eva Vitkova, and Petr Saha. "Effectiveness of Polymer Sheet Layer to Protect Hydrogel Dressings." In Trends in Colloid and Interface Science XXIV, 127–30. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-19038-4_22.

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Yang, Jin, Yue Yin, Harry C. Cramer, and Christian Franck. "The Penetration Dynamics of a Violent Cavitation Bubble Through a Hydrogel–Water Interface." In Challenges in Mechanics of Time Dependent Materials, Mechanics of Biological Systems and Materials & Micro-and Nanomechanics, Volume 2, 65–71. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-86737-9_9.

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Ikai, Hiroyo, Keisuke Nakamura, Midori Shirato, Taro Kanno, Atsuo Iwasawa, Yoshimi Niwano, Keiichi Sasaki, and Masahiro Kohno. "Bactericidal Effect of Hydroxyl Radical Generated by Photolysis of Hydrogen Peroxide." In Interface Oral Health Science 2011, 86–88. Tokyo: Springer Japan, 2012. http://dx.doi.org/10.1007/978-4-431-54070-0_14.

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Akbar, Teuku Fawzul, Christoph Tondera, and Ivan Minev. "Conductive Hydrogels for Bioelectronic Interfaces." In Neural Interface Engineering, 237–65. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-41854-0_9.

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Zoz, Henning, and Andreas Franz. "Hydrogen and Electromobility Agenda." In The Nano-Micro Interface, 567–82. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2015. http://dx.doi.org/10.1002/9783527679195.ch27.

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Soper, A. K. "Structural Studies of Water Near an Interface." In Hydrogen-Bonded Liquids, 147–58. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3274-9_12.

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Jurczyk, M., and W. Rajewski. "Nanocrystalline Hydrogen Storage Alloys Formed by Mechanical Alloying." In Interface Controlled Materials, 304–9. Weinheim, FRG: Wiley-VCH Verlag GmbH & Co. KGaA, 2005. http://dx.doi.org/10.1002/352760622x.ch49.

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Heinen, Matthias, Simon Homes, Gabriela Guevara-Carrion, and Jadran Vrabec. "Mass Transport Across Droplet Interfaces by Atomistic Simulations." In Fluid Mechanics and Its Applications, 251–68. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-09008-0_13.

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AbstractDue to availability of powerful computers and efficient algorithms, physical processes occurring at the micrometer scale can nowadays be studied with atomistic simulations. In the framework of the collaborative research center SFB-TRR75 “Droplet dynamics under extreme ambient conditions”, investigations of the mass transport across vapour-liquid interfaces are conducted. Non-equilibrium molecular dynamics simulation is employed to study single- and two-phase shock tube scenarios for a simple noble gas-like fluid. The generated data show an excellent agreement with computational fluid dynamics simulations. Further, particle and energy flux during evaporation are sampled and analysed with respect to their dependence on the interface temperature, employing a newly developed method which ensures a stationary process. In this context, the interface properties between liquid nitrogen and hydrogen under strong gradients of temperature and composition are investigated. Moreover, the Fick diffusion coefficient of strongly diluted species in supercritical CO$$_{2}$$ 2 is predicted by equilibrium molecular dynamics simulation and the Green-Kubo formalism. These results are employed to assess the performance of several predictive equations from the literature.
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Rossky, Peter J. "Structure and Dynamics of Water at Interfaces." In Hydrogen Bond Networks, 337–38. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-015-8332-9_30.

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Conference papers on the topic "Interface hydrogel"

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Edgerton, Alex, Joseph Najem, and Donald Leo. "A Hydrogel-Based Droplet Interface Lipid Bilayer Network." In ASME 2014 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/smasis2014-7580.

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In this work, we present a process for the fabrication of meso-scale hydrogel-based lipid bilayer arrays. The hydrogels support lipid monolayers at an oil-water interface, and when brought together, form stable bilayers. The substrates are formed using 3D printed molds and include built-in, customizable circuits patterned with silver paint. The system can be adapted to varying network sizes and circuit designs, and new arrays are fabricated quickly and inexpensively using common laboratory techniques. An enclosed 3×3 array with 3 mm spacing between neighboring hydrogels and electrodes to individually examine each bilayer has been created using this method. An alternative test setup was also developed to better observe the formation of bilayers in a small array. Using this setup, two bilayers were formed simultaneously, demonstrating the feasibility of this type of system and providing valuable information for expanding and improving the enclosed network. Many of the design concepts presented here can be adapted for use at smaller scales using microfabrication techniques.
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Sarles, Stephen A., and Donald J. Leo. "Encapsulated Interface Bilayers for Durable Biomolecular Materials." In ASME 2010 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. ASMEDC, 2010. http://dx.doi.org/10.1115/smasis2010-3752.

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This paper introduces the concept of hydrogel encapsulated interface bilayers as a novel approach for creating durable encapsulated biomolecular materials. The regulated attachment method (RAM) is used to form encapsulated interface bilayers from lipid-encased aqueous volumes contained in a deformable supporting substrate. Physically-encapsulated interface bilayers exhibit increased durability and portability over droplet interface bilayedrs and RAM enables the in situ bilayer formation without the need to dispense and arrange individual droplets. The results presented in this paper demonstrate that poly(ethylene glycol) dimethacrylate monomers (PEG-DMA, Mw = 1000), a photopolymerizable hydrogel monomer, and Irgacure 2959 photoinitiator can be incorporated into the aqueous phase in order to form hydrogel encapsulated interface bilayers. Following bilayer formation, exposure to an ultraviolet (UV) light initiates photopolymerization of the polymer on both sides of the bilayer, creating interface bilayers between solid aqueous phases. Electrical recordings of bilayer formation in the liquid state confirm that interface bilayers formed from photopolymerizable aqueous solutions have both high electrical resistances > 1GΩ necessary for observing transmembrane protein gating and survive the UV curing procedure required to polymerize the hydrogel. Photopolymerization for 60 seconds using a 1W hand held UV spot cure light produced water-swollen solids on both sides of the membrane. Hydrogel encapsulated interface bilayers last for hours to days and retain the fluidity necessary for delivering alamethicin proteins to the interface.
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Takehara, H., A. Nagaoka, J. Noguchi, T. Akagi, H. Kasai, and T. Ichiki. "Brain interface device with permeable hydrogel membrane for in situ analysis of neural cells." In 2011 International Conference on Solid State Devices and Materials. The Japan Society of Applied Physics, 2011. http://dx.doi.org/10.7567/ssdm.2011.h-4-4.

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Vukasinovic, Jelena, and Ari Glezer. "Flow Through a Micro-Bioreactor in a Neural Interface System." In ASME 2004 International Mechanical Engineering Congress and Exposition. ASMEDC, 2004. http://dx.doi.org/10.1115/imece2004-59598.

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A micro-bioreactor is developed for in vitro, controlled, growth of three-dimensional dissociated neural cultures that enables simultaneous, multipoint, electrical and fluidic interfacing, monitoring and recording of the response signals that are relevant to the studies of traumatic injury. Present experiments focus on the microfluidic system that is used to control the spatial concentration of nutrients and stimuli in the incubated tissue. The three-dimensional cellular environment in a micro-bioreactor is controlled by means of convective and diffusive fluidic processes to improve the neural cell survival rate, direct the cell growth and examine the network formation. To achieve global and local manipulation of the critical cell functions, flow within the reactor is induced from arrays of micro-machined nozzles in planar surfaces and within microscale hydrogel scaffolding. The flow and concentration fields within reactor are analyzed using microscale particle image velocimetry (PIV) and fluorescence. The flow within 25 μm thick layers between microfabricated structures is investigated using image-processing algorithms that are developed to improve spatial resolution by excluding out-of-focus particles. Mixing induced by delivery of stimuli/nutrients and waste extraction is considered by following the time-evolution and spatial propagration of the mixing front between the liquids based on the intensity of reflected light that is previously calibrated with concentration.
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Northwood, E., R. Kowalski, and J. Fisher. "An In-Vitro Investigation of Sliding Friction Between Biomaterials for Cartilage Substitution and Articular Cartilage." In World Tribology Congress III. ASMEDC, 2005. http://dx.doi.org/10.1115/wtc2005-63350.

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Understanding friction and wear of biomaterials when in contact with articular cartilage is vital within the development of future hemi-arthroplasty and cartilage substitution. This study aimed to compare the frictional properties of single phase and biphasic polymeric materials against articular cartilage. Continuous sliding friction was applied by means of a simple geometry wear simulator. The single-phase polymers produced peak frictional values of 0.37(±0.02). The biphasic hydrogel produced a peak frictional coefficient of 0.17(±0.05). It is postulated that this reduction in friction can be attributed to its biphasic properties, which instigates the fluid phase load carriage within the articular cartilage/hydrogel interface to be maintained for longer, reducing the frictional coefficient. This study illustrates the importance of biphasic properties within the tribology of future cartilage substitution materials.
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Bhadra, Jolly, Pramod K. Nampoothiri, Kamlesh J. Suthar, and D. Roy Mahapatra. "Effect of Core-Shell Structure of Hydrogel Beads on the Threshold Concentration of Water for Swelling and its pH Sensitivity." In ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-39583.

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In this paper we investigate the effect of core-shell structure of Sodium Alginate based hydrogel beads and their size on certain activation threshold concentration of water for applications in swelling and pH sensing. This type of hydrogel experiences diffusive pressure due to transport of certain free charges across its interface with a solvent or electrolyte. This process is essentially a dynamic equilibrium of the electric force field, stress in the polymeric network with cage like structure and molecular diffusion including phase transformation due to pressure imbalance between the hydrogel and its surroundings. The effect of pH of the solvant on the swelling rate of these beads has been studied experimentally. A mathematical model of the swelling process has been developed by considering Nernst–Planck equation representing the migration of mobile ions and H+ ions, Poisson equation representing the equilibrium of the electric field and mechanical field equation representing swelling of the gel. An attempt has been made to predict the experimentally observed phenomena using these numerical simulations. It is observed experimentally that certain minimum concentration called activation threshold concentration of the water molecules must be present in the hydrogel in order to activate the swelling process. For the required activation threshold concentration of water in the beads, the pH induced change in the rate of swelling is also investigated. This effect is analyzed for various different core-shell structures of the beads.
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Tamaddoni, Nima, and Andy Sarles. "Fabrication and Characterization of a Membrane Based Hair Cell Sensor That Features Soft Hydrogel Materials." In ASME 2012 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/smasis2012-8067.

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One of the most common sensory structures in nature is the hair cell. Examples of hair cells include the inner and outer hair cells in the inner ears of vertebrates, external sensory hairs on the legs of spiders, and neuromasts found along the lateral lines of fish. Recent work by Sarles and Leo demonstrated that self-assembly methods could be used to construct a membrane-based hair cell that responds to a physical disturbance of the hair. An artificial cell membrane (or lipid bilayer) formed at the interface of two lipid-encased hydrogel volumes, serves as the transduction element in the device. In this study, a revised sensor embodiment is presented in which the hair is fixed at its base by the encapsulating polymeric substrate. In addition, a highly elastic, photo-polymerizable aqueous gel (PEGDA, 6000g/mole) is used to further increase the resiliency of the hair and to provide a compliant cushion for the bilayer. These changes yield a considerably more durable hair cell sensor. We perform a series of experimental tests to characterize the transduction element (i.e. the bilayer) and the sensing current produced by free vibration of the hair, and we study the directional sensitivity of this hair cell embodiment by perturbing the hair in three directions. These tests demonstrate that the magnitude of the sensing current (30–300pA) is significantly affected by direction of perturbation, where the largest signals result from motion of the hair in a direction perpendicular to the plane of the bilayer.
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Temenoff, Johnna S. "A Modular System to Examine Fibroblastic Differentiation of Mesenchymal Stem Cells Under Tensile Loading in Response to Changes in the Extracellular Environment." In ASME 2011 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2011. http://dx.doi.org/10.1115/sbc2011-53704.

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Hundreds of thousands of injuries to ligaments, tendons or the joint capsule occur in the U.S. each year, resulting in significant reduction of quality of life for many patients [1]. Existing reconstruction techniques for torn tendons/ligaments result in significant morbidity and cannot fully recapitulate the native joint biomechanics, leading to secondary degeneration over time, such as premature osteoarthritis. Thus, tissue-engineered alternatives to current grafts, potentially using stem cells in combination with an appropriate scaffold, are greatly needed. In response, our laboratory is investigating a novel hydrogel system and a custom tensile bioreactor as an in-vitro model to study the formation of both fibrous (ligament) tissue and the ligament-bone interface. In these studies, we examine the effect of tensile loading and the degradability of the surrounding environment on cellular morphology and tendon/ligament extracellular matrix (ECM) production by mesenchymal stem cells (MSCs). In particular, the response of MSCs embedded within hydrogels with varying degrees of susceptibility to degradation by collagenase is explored. In addition, proof-of-principle experiments are presented to extend this system to examine the effect of co-culture of multiple cell types on differentiation of MSCs in a milieu that mimics the bone-ligament insertion.
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Brusina, Ksenia E., Alexey I. Nikiforov, Elizaveta A. Fomina, Dmitriy O. Testov, Kamil G. Gareev, and Nikita O. Sitkov. "Assessing the Propagation of Magnetic Nanoparticles in a Microfluidic Channel and their Behavior at the Suspension-Hydrogel Interface for On-Chip Modeling of Organs and Tissues." In 2024 Conference of Young Researchers in Electrical and Electronic Engineering (ElCon). IEEE, 2024. http://dx.doi.org/10.1109/elcon61730.2024.10468336.

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Sarles, Stephen A., Kevin L. Garrison, Taylor T. Young, and Donald J. Leo. "Formation and Encapsulation of Biomolecular Arrays for Developing Arrays of Membrane-Based Artificial Hair Cell Sensors." In ASME 2011 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. ASMEDC, 2011. http://dx.doi.org/10.1115/smasis2011-5095.

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Recent research in our group has shown that artificial cell membranes formed at the base of a hair-like structure can be used to sense air flow in a manner similar to the mechanotransduction processes found in mammalian hair cells. Our previous work demonstrated that a single artificial hair cell can be formed in an open substrate. However, that study also motivated the need to develop fully-encapsulated devices that feature arrays of hair-cells. Since the transduction element in this concept is an artificial cell membrane, or lipid bilayer, this work investigates two parallel substrate designs for providing encapsulation and a method for forming arrays of bilayers. In one effort, a flexible substrate with internal compartments for hosting the biomolecules and mating cap are constructed and experimentally characterized. The regulated attachment method (RAM) is used to form interface bilayers within the sealed device. Capacitance measurements of the sealed interface bilayer show that the sealing cap slightly compresses the bottom insert and reduces the size of the enclosed bilayer. Single channel measurements of alamethicin peptides further verify that the sealed device, which is also leak-proof under water, can be used to detect the insertion and gating activity of transmembrane proteins in the membrane. The second effort pursued herein is the fabrication and initial testing of a method to form arrays of interface bilayers by using anchored hydrogel pads that support curved aqueous lenses in oil. In this fashion, the configuration of the array does not require manipulating droplets, but instead depends on the arrangement of the built-in gels used to support the aqueous lenses. As with RAM, mechanical force is used to promote contact of adjacent aqueous lenses held in the flexible substrate. Initial tests show that gel-supported lenses can be used for forming multiple lipid bilayers within the device and that these interfaces can be interrogated individually or collectively using an electrode switching circuit.
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Reports on the topic "Interface hydrogel"

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Jones, Reese E., Royce Reyes, Xiaowang Zhou, Michael E. Foster, Dan Catalin Spataru, and Doug E. Spearot. Hydrogen diffusion across interfaces in zirconium. Office of Scientific and Technical Information (OSTI), December 2019. http://dx.doi.org/10.2172/1592901.

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Gupta, Alexander. Materials and Interfaces for Electrocatalytic Hydrogen Production and Utilization. Office of Scientific and Technical Information (OSTI), February 2021. http://dx.doi.org/10.2172/1768432.

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Vilim, R. B. Dynamic modeling efforts for system interface studies for nuclear hydrogen production. Office of Scientific and Technical Information (OSTI), August 2007. http://dx.doi.org/10.2172/919326.

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Hirofumi Ohashi and Steven R. Sherman. Tritium Movement and Accumulation in the NGNP System Interface and Hydrogen Plant. Office of Scientific and Technical Information (OSTI), June 2007. http://dx.doi.org/10.2172/919556.

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Parkins. L51806 Effects of Hydrogen on Low-pH Stress Corrosion Crack Growth. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), July 1998. http://dx.doi.org/10.55274/r0010142.

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There is circumstantial evidence of hydrogen playing a role in, so called, low pH SCC of pipeline steel, but direct evidence for such is lacking. Resolution of this situation is of practical importance because of its implications for modeling. Thus, existing models for high pH SCC of pipelines are based upon a dissolution controlled mechanism of crack growth, but such models will not be applicable to low pH SCC if hydrogen is involved with the latter. Measurements have been made of the permeation of hydrogen into X52 and X60 pipeline steels at various potetials while exposed to a simulated ground water containing different amounts of carbon dioxide, related to the conditions thought to be associated with transgranular stress corrosion cracking of pipelines. As a consequence of these measurements it is now known unequivocally that hydrogen enters the steel for all such solutions over wide ranges of potential, including those most likely involved in the cracking of pipelines, and with such entry enhanced as the amount of carbon dioxide present in the solution increased. For a given set of environmental conditions, it was found that films on the surface of the pipe, such as may exist in service conditions, could hinder, but not prevent, the ingress of hydrogen. Hydrogen in steel is usually regarded as being trapped at dislocations, grain boundaries or interfaces between the matrix and second phase particles and measurements relating to such indicate that the X60 steel contains appreciably fewer traps than the X52 steel for equivalent charging conditions. However, the trapped hydrogen was found to have no significant influence on the ductility of the steels when subsequently tested in air, although the ductility was impaired by thxe continued ingress of hydrogen when equivalent tests were conducted in the presence of the charging solution. No convincing evidence has been obtained for the ingress of hydrogen into the steels facilitating the early stages of plasticity under exposure conditions relating to those involved in low pH stress corrossion cracking. The most probable mechanism of stress corrosion crack growth in pipeline steel in the solutions studied and at potentials likely to obtain in service involves both dissolution and hydrogen ingress to the steel, although the interactions of those two factors in the fracture process remain speculative.
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Bruce. L51942 Refinement of Cooling Rate Prediction Methods for In-Service Welds. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), July 2003. http://dx.doi.org/10.55274/r0010435.

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Welds made onto in-service pipeline are particularly susceptible to hydrogen cracking because of the fast weld cooling rates that tend to result from the ability of the flowing contents to remove heat from the pipe wall. The most commonly used procedures for controlling the risk of hydrogen cracking rely on the use of a sufficiently high heat input level. Two methods currently exist for predicting required heat input levels for welds made onto in-service pipelines: thermal analysis computer modeling and the heat-sink capacity measurement method. The objective of this project was to refine these two complementary methods, and to investigate alternative approaches. The project was divided into three distinct tasks: further refinement of the PRCI Thermal Analysis Model for Hot Tap Welding, standardization of heat-sink capacity measurement, and investigation of alternative approaches to cooling rate prediction. The primary link between the PRCI model and the heat-sink capacity measurement method is the ability of the model to predict the heat-sink capacity of an operating pipeline. Detailed descriptions of user interface modifications required to incorporate the ability to enter the individual heating parameters of interest and have the model calculate the heating rate were developed.
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Bruce and Yushanov. L52056 Enhancement of PRCI Thermal Analysis Model for Assessment of Attachments. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), August 2004. http://dx.doi.org/10.55274/r0010436.

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Abstract:
Welds made onto in-service pipelines tend to cool at an accelerated rate as the result of the flowing content"s ability to remove heat from the pipe wall. These welds are therefore likely to have high heat-affected zone (HAZ) hardness values and to be susceptible to hydrogen cracking. The use of thermal analysis modeling allows welding parameters (i.e., required heat input levels) to be selected based on anticipated weld cooling rates. Both the Battelle model and the recently developed PRCI Thermal Analysis Model for Hot Tap Welding assume that the pipe material is the most susceptible material being welded. Some attachments (e.g., hot formed fittings, etc.) have a significantly less favorable chemical composition (i.e., higher carbon equivalent level) than the pipe material. As a result, for some in-service welding applications, the attachment material may be more susceptible to cracking than the pipe material. Modifications were made to the finite-element solver of the PRCI model to enable hardness prediction in both the pipe and attachment material. The source code for the modified finite-element solver was provided to Technical Toolboxes - PRCI"s commercial partner for software marketing and distribution. The required modifications to the user interface were also developed. In addition, user interface modifications required to rectify a number of faults that were identified and to improve the user interface were also developed. The incorporation of these enhancements and improvements, which are described herein, will require modification by Technical Toolboxes of the Visual Basic-based version of the software that is currently being marketed (V4.2.1). Following the incorporation of these enhancements and improvements, validation trials should be carried out.
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C Taylor, R Kelly, and M Neurock. First Principles Calculations of Electrochemically Controlled Hydrogen Mobility and Uptake at the Ni(111)H2O Interface. Office of Scientific and Technical Information (OSTI), November 2005. http://dx.doi.org/10.2172/875455.

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9

Eschbach, E. J., and C. W. Enderlin. 1/12-Scale mixing interface visualization and buoyant particle release tests in support of Tank 241-SY-101 hydrogen mitigation. Office of Scientific and Technical Information (OSTI), October 1993. http://dx.doi.org/10.2172/10194717.

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Ulrich, Thomas A., Roger Lew, Torrey J. Mortenson, Jooyoung Park, Heather D. Medema, and Ronald Laurids Boring PhD. An Integrated Energy Systems Prototype Human-System Interface for a Steam Extraction Loop System to Support Joint Electricity-Hydrogen Flexible Operations. Office of Scientific and Technical Information (OSTI), March 2020. http://dx.doi.org/10.2172/1608624.

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