Article
Biochemistry & Molecular Biology
Mikulas Cernohlavek, Martina Brandejsova, Petr Stepan, Hana Vagnerova, Martina Hermannova, Katerina Kopecka, Jaromir Kulhanek, David Necas, Martin Vrbka, Vladimir Velebny, Gloria Huerta-Angeles
Summary: Studies have shown that HA-C12 can reduce the friction coefficient, while the combination of trehalose/HA or HAC12 can enhance mucoadhesiveness up to eighty-fold. These results provide valuable information for the design of highly performing eye drop formulations and contribute to increasing knowledge of these preparations.
Article
Chemistry, Multidisciplinary
Weifeng Lin, Jacob Klein
Summary: Healthy articular cartilage has very low friction coefficients, which help reduce wear and tear and cartilage degradation, maintaining the balance of chondrocyte functions. Investigating the origins of low friction in articular cartilage is crucial for alleviating disease symptoms and slowing or reversing the degradation process. Recent studies have focused on the mechanisms of joint lubrication and the development of natural and bio-inspired lubricants.
ADVANCED MATERIALS
(2021)
Article
Engineering, Mechanical
R. Taylor, I Sherrington
Summary: A new equation is proposed to calculate the proportion of mixed/boundary friction in a contact based on experimental data, and it is revealed that some commonly used rough surface contact models underestimate this type of friction. The new model suggests treating rough surface contact modeling as a growth/decay process, and the consequences of this approach are discussed.
TRIBOLOGY INTERNATIONAL
(2022)
Article
Chemistry, Physical
Ke Ren, Hongping Wan, Hans J. Kaper, Prashant K. Sharma
Summary: In this study, hyaluronic acid (HA) was conjugated with dopamine to form HADN, which exhibited adhesive properties while retaining viscosity enhancement capacity. It was found that HADN could enhance cartilage lubrication through adsorption onto collagen, providing better protection for cartilage compared to HA alone.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Multidisciplinary Sciences
Yiting Lei, Yuping Wang, Jieliang Shen, Zhengwei Cai, Chen Zhao, Hong Chen, Xiaoji Luo, Ning Hu, Wenguo Cui, Wei Huang
Summary: Researchers have developed a new type of hyaluronic acid-based HMs with rapamycin-liposome coating, which can form self-renewable hydration layers and release autophagy activator for improving joint lubrication, maintaining cellular homeostasis, and alleviating joint wear and osteoarthritis progression.
Article
Chemistry, Physical
Hongping Wan, Ke Ren, Hans J. Kaper, Prashant K. Sharma
Summary: A nanostructured film based on hyaluronic acid and glutathione was proposed to enhance lubrication between cartilage and PCU. The coating of HADN-Glu effectively protected cartilage and exhibited successful grafting onto the PCU surface, enabling enhanced lubrication for potential implant design.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2021)
Article
Engineering, Mechanical
Ke Ren, Miguel Alejandro Reina Mahecha, Maike Hubner, Zhiwei Cui, Hans J. Kaper, Hugo C. van der Veen, Prashant K. Sharma
Summary: The objective of this research is to observe the level of cartilage damage present in knee arthroplasty patients and to understand the friction and creep behavior of enzymatically degraded bovine cartilage in vitro. The results showed that enzymatic treatment significantly decreased the coefficient of friction at 4 N, while higher coefficient of friction was observed from chondroitinase ABC degraded cartilage at 40 N.
Article
Chemistry, Multidisciplinary
Peng Yu, Yanyan Li, Hui Sun, Hongbo Zhang, Han Kang, Peng Wang, Qiangwei Xin, Chunmei Ding, Jing Xie, Jianshu Li
Summary: A photothermal dual-bionic nanozyme, mimicking antioxidases and hyaluronan synthase, has been developed for effective osteoarthritis (OA) therapy. It can produce heat, scavenge free radicals, and promote chondrogenesis even under inflammatory conditions. This nanozyme regulates anabolic and catabolic processes simultaneously, thereby effectively restoring joint homeostasis and demonstrating an admirable photothermally therapeutic effect on OA.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Physical
Thomas Le Goff, Tung B. T. To, Olivier Pierre-Louis
Summary: We developed a model for the nonlinear response of a lubricated contact involving a lipid membrane, and observed various dynamic behaviors of the membrane under different shear rates, leading to changes in wrinkles and mechanical properties.
Article
Engineering, Mechanical
Simon Stephan, Sebastian Schmitt, Hans Hasse, Herbert M. Urbassek
Summary: Lubricated contact processes were studied through molecular dynamics simulations, covering the entire range of the Stribeck curve. The lateral movement of solid bodies at different gap heights was studied, with methane and decane as lubricants. The study revealed three lubrication regimes and their transition regions: boundary lubrication, mixed lubrication, and hydrodynamic lubrication. The formation of a tribofilm, where lubricant molecules are immersed into the metal surface, was found to have important consequences for the contact process. The behavior of methane and decane in the three lubrication regimes differed due to the different mechanisms observed for tribofilm formation.
Review
Chemistry, Physical
Yifeng Cao, Jacob Klein
Summary: This review presents the relationship between the molecular composition of the interfacial complex and the lubrication behavior of the lipid-based boundary layers, which could be beneficial for designing boundary lubricants for intra-articular injection for the treatment of early osteoarthritis.
CURRENT OPINION IN COLLOID & INTERFACE SCIENCE
(2022)
Article
Engineering, Chemical
Shuangbiao Liu, Q. Jane Wang, Yip-Wah Chung, Stephen Berkebile
Summary: The article discusses the lubrication-contact interface conditions (LCICs) and proposes mathematical LCICs to address the interface issue between fluid lubrication and solid contacts. Through practical testing, a new mixed/boundary elastohydrodynamic lubrication solver has been successfully developed, capable of accurately capturing film thickness and pressure behaviors involving solid contacts.
Article
Chemistry, Physical
Junqin Shi, Hang Li, Yang Lu, Lin Sun, Shaofeng Xu, Xiaoli Fan
Summary: The synergistic effect of organic friction modifiers (OFMs) consisting of glycerol monolaurate (GML) and tri-n-octylamine (N888) in base oil was studied using molecular dynamics simulations. The results showed that N888 molecules interspersed among GML molecules to form an intercoordination adsorption film. The system with a ratio of 3:1 of GML to N888 exhibited the best synergistic lubrication with the lowest friction coefficient. Chemisorption of GML molecules on the Fe2O3 surface was confirmed by density function theory. High shear velocity led to the breakage of the adsorption film and increased friction, while contact pressure helped reduce friction. The synergistic lubrication was attributed to the interface slip between the base oil and OFM films, rather than the interlaminar shear caused by an imbalanced combination or high shear velocity.
APPLIED SURFACE SCIENCE
(2023)
Article
Multidisciplinary Sciences
Asghar Shirani, Yuzhe Li, Osman Levent Eryilmaz, Diana Berman
Summary: The study reveals the anti-wear capability of metal nitride-copper nanocomposite coatings in liquid hydrocarbon environments. The formation of carbon-based protective films at the sliding interface contributes to the significant reduction of wear. Analysis of tribological characteristics under different conditions provides insights into the tribocatalysis mechanism facilitating the formation of zero-wear coatings.
SCIENTIFIC REPORTS
(2021)
Article
Engineering, Mechanical
Jie Guo, Yanxin Si, Qiang Liu, Xinjian Cao, Jun Cheng, Jun Yang, Weimin Liu
Summary: Through the study of the stribeck curve, static friction, and a series of fixed-speed friction tests for steel self-mated pairs under gallium lubrication, the lubrication regimes and transition laws are revealed. In the sliding speed ranging from 10-8 to 1.4 m/s and the normal load ranging from 2 to 20 N, gallium can only provide boundary and mixed lubrication. Uniformly distributed or island-like distributed gallium-rich films are formed under boundary or mixed lubrication regimes, respectively. The different formation mechanisms are revealed. The failure of the gallium-rich film is mainly related to the average contact stress of the frictional interfaces.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Clinical Neurology
Rasmus Holmboe Dahl, Rene Wugt Larsen, Esben Thormann, Goetz Benndorf
Summary: This study reports two cases of cerebral polymer coating embolism during neuroendovascular treatment, with analysis of the composition and origins of the fragments. It emphasizes the potential consequences of coating delamination during endovascular therapy.
INTERVENTIONAL NEURORADIOLOGY
(2022)
Article
Dermatology
Fatemeh Keshavarzi, Nina Ostergaard Knudsen, Niloufarsadat Mirmahdi Komjani, Morten F. Ebbesen, Jonathan R. Brewer, Shadi Jafarzadeh, Esben Thormann
Summary: The study found that incorporating a hydrophobic film former can reduce sunscreen wash-off due to sweating, but excessive amounts may have a negative impact on sunscreen distribution. Additionally, the addition of water-absorbing particles can have both positive and negative effects on sunscreen substantivity, depending on the properties of the particles. Adding small water-absorbing particles that change wetting behavior may decrease sunscreen wash-off and redistribution, making sunscreen formulations more sweat-resistant.
SKIN RESEARCH AND TECHNOLOGY
(2022)
Article
Multidisciplinary Sciences
Bin Wang, Einstom Engay, Peter R. Stubbe, Saeed Z. Moghaddam, Esben Thormann, Kristoffer Almdal, Aminul Islam, Yi Yang
Summary: In this study, we demonstrate a method for achieving high precision internal mechanical property gradients in 3D printing using tomographic volumetric printing (TVP) technology. By utilizing visible and UV light sources in conjunction with specific chemical reactions, we achieve full 3D stiffness control. Additionally, we identify the role of reactive transport of radical inhibitors in shaping the workpiece and limiting the achievable stiffness contrast range.
NATURE COMMUNICATIONS
(2022)
Article
Materials Science, Multidisciplinary
Saeed Zajforoushan Moghaddam, Runtian Qie, Esben Thormann
Summary: The study found that protein-polyphenol complexation can improve the water resistance of protein-based adhesives to a commercial level.
ACS APPLIED POLYMER MATERIALS
(2022)
Article
Engineering, Biomedical
Shiva Taheri, Zahra Sadat Ghazali, Leila Montazeri, Fatemeh Ale Ebrahim, Jafar Javadpour, Khorshid Kamguyan, Esben Thormann, Philippe Renaud, Shahin Bonakdar
Summary: The effect of cell imprinted substrates on the differentiation of ADSCs was investigated. The results showed that cell imprinted substrates can induce differentiation signals better than engineered lithographic substrates. Therefore, the patterns must include nano-topographies to have reliable and reproducible engineered substrates.
BIOMEDICAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Frederik Hegaard, Robert Biro, Koosha Ehtiati, Esben Thormann
Summary: In this study, the interactions between mobile ions and immobile charges within a sulfobetaine-based polyzwitterionic film were systematically investigated. The swelling behavior of the film in the presence of different salts was compared, and it was found that specific types of anions significantly influenced the swelling of the polycationic films. Furthermore, it was observed that the degree of swelling of the zwitterionic films depended on the anion type and increased with increasing ionic strength.
Article
Chemistry, Multidisciplinary
Runtian Qie, Saeed Zajforoushan Moghaddam, Esben Thormann
Summary: In this study, a method combining dopamine-assisted deposition and layer-by-layer assembly was investigated as an efficient way to prepare coatings with adjustable thickness, roughness, and functional properties. The versatile chemistry of dopamine allows for the co-deposition of various functional materials, such as polymers, ions, and nanoparticles, within the coating. Additionally, the layer-by-layer approach allows for control over coating thickness, surface roughness, and chemical composition in the vertical direction. The benefits of using this method for fabricating single- and multi-component coatings were demonstrated.
Article
Chemistry, Multidisciplinary
Frederik Hegaard, Esben Thormann
Summary: In this study, the effects of composition, salt concentration, and ion specificity on the pH responsiveness of covalently crosslinked chitosan and alginate dialdehyde multilayer films were systematically investigated. The results showed that the swelling responses of the films varied with the multilayer composition, pH, and ion specificity, and were consistent with those observed for other types of polyelectrolyte films. Additionally, it was demonstrated that the pH responsiveness of the multilayer films strongly depended on the ionic condition under which the responses were measured.
Article
Clinical Neurology
Rasmus Holmboe Dahl, Rene Wugt Larsen, Esben Thormann, Goetz Benndorf
Summary: During endovascular therapy, backloading of polymer-coated microguidewires can cause damage to the coating, resulting in the formation of small polymer fragments. Therefore, it is recommended to minimize the use of backloaded polymer-coated microguidewires and opt for more stable hydrophilic coatings and less traumatic insertion tools.
CLINICAL NEURORADIOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Runtian Qie, Saeed Zajforoushan Moghaddam, Esben Thormann
Summary: Coacervation of poly(propylene oxide) and tannic acid, driven by hydrogen bonding, creates a tacky viscous material with strong underwater adhesion on various surfaces. By designing a two-component system, this adhesive can cure underwater through amine-epoxide reactions, providing both commercial competitiveness and waterproof bonding.
ACS APPLIED POLYMER MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Junjie Kang, Saeed Zajforoushan Moghaddam, Esben Thormann
Summary: In this study, mussel-inspired chemistry was used to develop self-cross-linkable chitosan-alginate complexes. The addition of catechol groups enhanced the self-cross-linking property and cohesive properties of the complexes.
Article
Materials Science, Multidisciplinary
Junjie Kang, Saeed Zajforoushan Moghaddam, Rene Wugt Larsen, Esben Thormann
Summary: This study investigates the potential of combining epsilon-polylysine and tannic acid to develop bio-based adhesives with enhanced water resistance. The complexes formed at different pH values showed different adhesion strength and water resistance.
ACS APPLIED POLYMER MATERIALS
(2023)
Review
Nanoscience & Nanotechnology
Koosha Ehtiati, Johannes Eiler, Agnieszka Bochynska, Louis Lech Nissen, Esben Strobech, Lene Feldskov Nielsen, Esben Thormann
Summary: Skin electrical properties are important for recording biopotentials with electrophysiological sensors. Artificial skin models, which mimic the electrochemical properties of skin, are commonly used for testing sensor systems due to complications with testing on living tissues. This Review aims to provide a systematic understanding of the relation between skin structure and electrochemical behavior, as well as review artificial skin models and suggest future studies based on a comparison with real skin behavior.
ACS APPLIED BIO MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Achebe N. O. Nzulumike, Esben Thormann
Summary: Medical devices inserted in blood vessels carry the risk of thrombosis, making surface properties crucial. Fibrinogen protein adsorption on biomaterial surfaces and subsequent polymerization into an insoluble fibrin clot is the key step in surface-induced coagulation. This study characterizes the thrombogenic properties of cardiovascular biomaterials and devices, identifying stainless steel and amorphous fluoropolymer as preferable options with low fibrinogen recruitment. Morphological analysis reveals fiber structures on metallic surfaces and fractal branched structures on polymeric surfaces. The study also explores fibrin adsorption on vascular guidewires and its correlation with uncoated guidewire morphology and raw stainless-steel biomaterials.
ACS APPLIED BIO MATERIALS
(2023)
Article
Chemistry, Physical
Achebe N. O. Nzulumike, Robert A. Biro, Esben Thormann
Summary: Biomaterial-associated thrombosis is a persistent challenge in medical device implantation, and antithrombogenic coatings are developed to prevent blood clot formation. Charged polymers show potential as coating materials, and we investigate these polymer coatings in the context of biomaterial-associated thrombosis. Our findings indicate that different polymer interfaces lead to different fibrin structures, with surface-induced fibrin formation dominating for anionic polymers and bulk-formed fibrin dominating for cationic polymers. Coatings containing zwitterionic sulfobetaine groups are identified as promising candidates for antithrombogenic biomaterials.
Article
Chemistry, Physical
Yiping Yin, Zhe Wang, Hua Zou
Summary: This study presents a novel method for preparing dimpled polymer-silica nanocomposite particles using interfacial swelling-based seeded polymerization. The optimized conditions allow for a relatively high percentage of dimpled particles to be achieved.
Article
Chemistry, Physical
Brenden D. Hoehn, Elizabeth A. Kellstedt, Marc A. Hillmyer
Summary: Porous materials with nanometer-scale pores have important applications as nanoporous membranes. In this study, ABA triblock copolymers were used as precursors to produce nanoporous polymeric membranes (NPMs) in thin film form by degrading the end blocks. Polycyclooctene (PCOE) NPMs with tunable pore sizes were successfully prepared using solvent casting technique. Oxygen plasma etching was employed to improve the surface porosity and hydrophilicity of the membranes. This study provides a straightforward method to produce tough NPMs with high porosity and hydrophilic surface properties.
Article
Chemistry, Physical
Vladislav S. Petrovskii, Stepan I. Zholudev, Igor I. Potemkin
Summary: This article investigates the behavior of linear and ring polypeptide chains in aqueous solution and explores the properties of the complexes formed by these chains with oppositely charged surfactants. The results demonstrate that the complexes of linear supercharged unfolded polypeptides and the corresponding surfactants exhibit impressive adhesive properties.
Article
Chemistry, Physical
Merve Cevik, Serkan Dikici
Summary: Cardiovascular diseases are a leading cause of death globally, and vascular grafts are a promising treatment option. This study focuses on tissue-engineered vascular grafts (TEVGs) using decellularized parsley stems as a potential biomaterial. The decellularized parsley stems showed suitable properties for TEVGs, providing a suitable environment for human endothelial cells to form a pseudo endothelium. This study showcases the potential of using parsley stems for TEVGs.
Article
Chemistry, Physical
Gustavo A. Vasquez-Montoya, Tadej Emersic, Noe Atzin, Antonio Tavera-Vazquez, Ali Mozaffari, Rui Zhang, Orlando Guzman, Alexey Snezhko, Paul F. Nealey, Juan J. de Pablo
Summary: The optical properties of liquid crystals are typically controlled by electric fields. In this study, we investigate the effects of microfluidic flows and acoustic fields on the molecular orientation and optical response of nematic liquid crystals. We identify several previously unknown structures and explain them through calculations and simulations. These findings hold promise for the development of new systems combining sound, flow, and confinement.
Article
Chemistry, Physical
Xinjun Wu, Xin Guan, Shushu Chen, Jiangpeng Jia, Chongyi Chen, Jiawei Zhang, Chuanzhuang Zhao
Summary: This research presents a novel shape memory hydrogel with a remodelable permanent shape and programmable cold-induced shape recovery behavior. The hydrogel is prepared using specific treatment methods to achieve shape fixation by heating and shape recovery by cooling. Additionally, deformable devices can be obtained by assembling hydrogel blocks with different concentrations.
Article
Chemistry, Physical
Rebecca Hengsbach, Gerhard Fink, Ulrich Simon
Summary: This study examines the properties of DNA functionalized pNipmam microgels and pure pNipmam microgels at different concentrations of sodium chloride and in PBS solutions using temperature dependent H-1-NMR measurements. The results show that DNA modification affects the volume phase transition temperature and the addition of salt and PBS further enhances this effect.
Article
Chemistry, Physical
Ningyi Li, Junhong Li, Lijingting Qing, Shicheng Ma, Yao Li, Baohui Li
Summary: This paper investigates the self-assembly behavior of colloids with competing interactions under spherical confinement and finds that different ordered structures can be formed under different sized spherical confinements. Moreover, more perforated structures are formed in smaller spheres.
