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Yang Y, You X, Deng T, Li M, Liu Y, Xu M, Nie Y, Xu SM, Shen B. Cartilage-Inspired, High-Strength, and Heat-Tolerant Lubricating Hydrogels by Macrophase Separation. Biomacromolecules 2024; 25:3554-3565. [PMID: 38729918 DOI: 10.1021/acs.biomac.4c00072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2024]
Abstract
Hydrogels are considered as a potential cartilage replacement material based on their structure being similar to natural cartilage, which are of great significance in repairing cartilage defects. However, it is difficult for the existing hydrogels to combine the high load bearing and low friction properties (37 °C) of cartilage through sample methods. Herein, we report a facile and new fabrication strategy to construct the PNIPAm/EYL hydrogel by using the macrophase separation of supersaturated N-isopropylacrylamide (NIPAm) monomer solution to promote the formation of liposomes from egg yolk lecithin (EYL) and asymmetric template method. The PNIPAm/EYL hydrogels possess a relatively high compressive strength (more than 12 MPa), fracture energy (9820 J/m2), good fatigue resistance, lubricating properties, and excellent biocompatibility. Compared with the PNIPAm hydrogel, the friction coefficient (COF 0.046) of PNIPAm/EYL hydrogel is reduced by 50%. More importantly, the COF (0.056) of PNIPAm/EYL hydrogel above lower critical solution temperature (LCST) does not increase significantly, exhibiting heat-tolerant lubricity. The finite element analysis further proves that PNIPAm/EYL hydrogel can effectively disperse the applied stress and dissipate energy under load conditions. This work not only provides new insights for the design of high-strength lubricating hydrogels but also lays a foundation for the treatment of cartilage injury as a substitute material.
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Affiliation(s)
- Yang Yang
- Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, Chengdu 610041, China
- The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials (MoE), National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), State Key Laboratory of Polymer Materials Engineering, Engineering Research Center of Eco-friendly Polymeric Materials, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Xuanhe You
- Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Tao Deng
- School of Mechanical Engineering, Sichuan University, Chengdu 610065, China
| | - Mingyang Li
- Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Yuan Liu
- Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Mingjie Xu
- Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Yong Nie
- Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Shi-Mei Xu
- The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials (MoE), National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), State Key Laboratory of Polymer Materials Engineering, Engineering Research Center of Eco-friendly Polymeric Materials, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Bin Shen
- Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, Chengdu 610041, China
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2
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Hayler HJ, Groves TS, Guerrini A, Southam A, Zheng W, Perkin S. The surface force balance: direct measurement of interactions in fluids and soft matter. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2024; 87:046601. [PMID: 38382100 DOI: 10.1088/1361-6633/ad2b9b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 02/21/2024] [Indexed: 02/23/2024]
Abstract
Over the last half-century, direct measurements of surface forces have been instrumental in the exploration of a multitude of phenomena in liquid, soft, and biological matter. Measurements of van der Waals interactions, electrostatic interactions, hydrophobic interactions, structural forces, depletion forces, and many other effects have checked and challenged theoretical predictions and motivated new models and understanding. The gold-standard instrument for these measurements is thesurface force balance(SFB), orsurface forces apparatus, where interferometry is used to detect the interaction force and distance between two atomically smooth planes, with 0.1 nm resolution, over separations from about 1 µm down to contact. The measured interaction forcevs.distance gives access to the free energy of interaction across the fluid film; a fundamental quantity whose general form and subtle features reveal the underlying molecular and surface interactions and their variation. Motivated by new challenges in emerging fields of research, such as energy storage, biomaterials, non-equilibrium and driven systems, innovations to the apparatus are now clearing the way for new discoveries. It is now possible to measure interaction forces (and free energies) with control of electric field, surface potential, surface chemistry; to measure time-dependent effects; and to determine structurein situ. Here, we provide an overview the operating principles and capabilities of the SFB with particular focus on the recent developments and future possibilities of this remarkable technique.
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Affiliation(s)
- Hannah J Hayler
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom
| | - Timothy S Groves
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom
| | - Aurora Guerrini
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom
| | - Astrid Southam
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom
| | - Weichao Zheng
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom
| | - Susan Perkin
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom
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3
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Qin X, Dong M, Li Q. Insight into the hydration friction of lipid bilayers. NANOSCALE 2024; 16:2402-2408. [PMID: 38226708 DOI: 10.1039/d3nr05517e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2024]
Abstract
Hydration layers formed on charged sites play crucial roles in many hydration lubrication systems in aqueous media. However, the underlying molecular mechanism is not well understood. Herein, we explored the hydration friction of lipid bilayers with different charged headgroups at the nanoscale through a combination of frequency-modulation atomic force microscopy and friction force microscopy. The nanoscale friction experiments showed that the hydration friction coefficient and frictional energy dissipation of a cationic lipid (DPTAP) were much lower than those of zwitterionic (DPPE) and anionic (DPPG) lipids. The hydration layer probing at the surfaces of different lipid bilayers clearly revealed the relationship between the charged lipid headgroups and hydration layer structures. Our detailed analysis demonstrated that the cationic lipid had the largest hydration force in comparison with zwitterionic and anionic lipids. These friction and hydration force results indicated that the difference of the lipid headgroup charge resulted in different hydration strengths which led to the difference of hydration friction behaviors. The findings in this study provide molecular insights into the hydration friction of lipid bilayers, which has potential implications for the development of efficient hydration lubrication systems with boundary lipid bilayers in aqueous media.
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Affiliation(s)
- Xiaoxue Qin
- Key Laboratory of Colloid and Interface Chemistry of the Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China.
| | - Mingdong Dong
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, DK 8000, Denmark.
| | - Qiang Li
- Key Laboratory of Colloid and Interface Chemistry of the Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China.
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Mielke S, Sorkin R, Klein J. Effect of cholesterol on the mechanical stability of gel-phase phospholipid bilayers studied by AFM force spectroscopy. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2023; 46:77. [PMID: 37672138 DOI: 10.1140/epje/s10189-023-00338-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 08/24/2023] [Indexed: 09/07/2023]
Abstract
The remarkably low sliding friction of articular cartilage in the major joints such as hips and knees, which is crucial for its homeostasis and joint health, has been attributed to lipid bilayers forming lubricious boundary layers at its surface. The robustness of such layers, and thus their lubrication efficiency at joint pressures, depends on the lipids forming them, including cholesterol which is a ubiquitous component, and which may act to strengthen of weaken the bilayer. In this work, a systematic study using an atomic force microscope (AFM) was carried out to understand the effect of cholesterol on the nanomechanical stability of two saturated phospholipids, DSPC (1,2-distearoyl-sn-glycero-3-phosphatidlycholine) and DPPC (1,2-dipalmitoyl-sn-glycero- phosphatidylcholine), that differ in acyl chain lengths. Measurements were carried out both in water and in phosphate buffer solution (PBS). The nanomechanical stability of the lipid bilayers was quantitatively evaluated by measuring the breakthrough force needed to puncture the bilayer by the AFM tip. The molar fractions of cholesterol incorporated in the bilayers were 10% and 40%. We found that for both DSPC and DPPC, cholesterol significantly decreases the mechanical stability of the bilayers in solid-ordered (SO) phase. In accordance with the literature, the strengthening effect of salt on the lipid bilayers was also observed. For DPPC with 10 mol % cholesterol, the effect of tip properties and the experimental procedure parameters on the breakthrough forces were also studied. Tip radius (2-42 nm), material (Si, Si3N4, Au) and loading rate (40-1000 nm/s) were varied systematically. The values of the breakthrough forces measured were not significantly affected by any of these parameters, showing that the weakening effect of cholesterol does not result from such changes in experimental conditions. As we have previously demonstrated that mechanical robustness improves the tribological performance of lipid layers, this study helps to shed light on the mechanism of physiological lubrication. Nanoindentation of SDPC bilayers.
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Affiliation(s)
- Salomé Mielke
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, 76100, Rehovot, Israel
| | - Raya Sorkin
- School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, 6997801, Tel Aviv, Israel.
| | - Jacob Klein
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, 76100, Rehovot, Israel.
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Dong Y, Kampf N, Schilt Y, Cao W, Raviv U, Klein J. Dehydration does not affect lipid-based hydration lubrication. NANOSCALE 2022; 14:18241-18252. [PMID: 36468753 PMCID: PMC9753160 DOI: 10.1039/d2nr04799c] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 11/22/2022] [Indexed: 06/17/2023]
Abstract
Phosphatidylcholine (PC) lipid bilayers at surfaces massively reduce sliding friction, via the hydration lubrication mechanism acting at their highly-hydrated phosphocholine headgroups, a central paradigm of biological lubrication, particularly at articular cartilage surfaces where low friction is crucial for joint well-being. Nanotribological measurements probed the effect on such lubrication of dehydration by dimethyl sulfoxide (DMSO), known to strongly dehydrate the phosphocholine headgroups of such PC bilayers, i.e. reduce the thickness of the inter-bilayer water layer, and thus expected to substantially degrade the hydration lubrication. Remarkably, and unexpectedly, we found that the dehydration has little effect on the friction. We used several approaches, including atomic force microscopy, small- and wide-angle X-ray scattering and all-atom molecular dynamics simulations to elucidate this. Our results show that while DMSO clearly removes hydration water from the lipid head-groups, this is offset by both higher areal head-group density and by rigidity-enhancement of the lipid bilayers, both of which act to reduce frictional dissipation. This sheds strong light on the robustness of lipid-based hydration lubrication in biological systems, despite the ubiquitous presence of bio-osmolytes which compete for hydration water.
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Affiliation(s)
- Yihui Dong
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, 76100, Israel.
| | - Nir Kampf
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, 76100, Israel.
| | - Yaelle Schilt
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Wei Cao
- Department of Physical Chemistry, School of Chemistry, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Uri Raviv
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Jacob Klein
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, 76100, Israel.
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Recent advances in superlubricity of liposomes for biomedical applications. Colloids Surf B Biointerfaces 2022; 218:112764. [PMID: 35973238 DOI: 10.1016/j.colsurfb.2022.112764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Revised: 07/18/2022] [Accepted: 08/07/2022] [Indexed: 11/23/2022]
Abstract
Achieving superlubricity, a state of lubrication where friction nearly vanishes, has become one of the most promising approaches to combat friction-induced energy dissipation and medical device failure. Phospholipids are amphiphilic molecules comprising highly hydrophilic phosphatidylcholine head groups as well as hydrophobic hydrocarbon chains, When solubilized, phospholipids can readily self-assemble to form different structures such as bilayers and vesicles (liposomes). Recently, liposomes have been identified as excellent lubricants, especially in the boundary lubrication regime the most common lubrication status in the field of biotribology. In this review, we summarize recent progress in employing liposomes as key players for employing superlubricity in biomedical applications. The relationship between lipids and liposomes, manufacturing approaches, lubrication regimes, and regulation mechanisms of liposomes are discussed. Finally, we indicate possible future directions for the use of liposome-mediated superlubricity in biomedical applications.
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7
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Cao Y, Klein J. Lipids and lipid mixtures in boundary layers: From hydration lubrication to osteoarthritis. Curr Opin Colloid Interface Sci 2022. [DOI: 10.1016/j.cocis.2021.101559] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Lin W, Klein J. Hydration Lubrication in Biomedical Applications: From Cartilage to Hydrogels. ACCOUNTS OF MATERIALS RESEARCH 2022; 3:213-223. [PMID: 35243350 PMCID: PMC8886567 DOI: 10.1021/accountsmr.1c00219] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 01/21/2022] [Indexed: 05/11/2023]
Abstract
In the course of evolution, nature has achieved remarkably lubricated surfaces, with healthy articular cartilage in the major (synovial) joints being the prime example, that can last a lifetime as they slide past each other with ultralow friction (friction coefficient μ = the force to slide surfaces past each other/load compressing the surfaces < 0.01) under physiological pressures (up to 10 MPa or more)). Such properties are unmatched by any man-made materials. The precise mechanism of low friction between such sliding cartilage tissues, which is closely related to osteoarthritis (OA), the most widespread joint disease, affecting hundreds of millions worldwide, has been studied for nearly a century, but is still not fully understood. Traditionally, the roles of load bearing by interstitial fluid within the cartilage bulk and that of thin exuded fluid films at the interface between the sliding cartilage surfaces have been proposed as the main lubrication mechanism. More recent work, however, suggests that molecular boundary layers at the surfaces of articular cartilage and other tissues play a major role in their lubrication. In particular, in recent years hydration lubrication has emerged as a new paradigm for boundary lubrication in aqueous media based on subnanometer hydration shells which massively reduce frictional dissipation. The vectors of hydration lubrication include trapped hydrated ions, hydrated surfactants, biological macromolecules, biomimetic polymers, polyelectrolytes and polyzwitterionic brushes, and close-packed layers of phosphatidylcholine (PC) vesicles, all having in common the exposure of highly hydrated groups at the slip plane. Among them, vesicles (or bilayers) of PC lipids, which are the most widespread lipid class in mammals, are exceptionally efficient lubricating elements as a result of the high hydration of the phosphocholine headgroups they expose. Such lipids are ubiquitous in joints, leading to the proposal that macromolecular surface complexes exposing PC bilayers are responsible for the remarkable lubrication of cartilage. Cartilage, comprising ∼70% water, may be considered to be a complex biological hydrogel, and studying the frictional properties of hydrogels may thus provide new insights into its lubrication mechanisms, leading in turn to novel, highly lubricious hydrogels that may be used in a variety of biomedical and other applications. A better understanding of cartilage lubrication could moreover lead to better treatments for OA, for example, through intra-articular injections of appropriate lubricants or through the creation of low-friction hydrogels that may be used as tissue engineering scaffolds for diseased cartilage. In this Account, we begin by introducing the concept and origin of hydration lubrication, extending from the seminal study of lubrication by hydrated simple ions to more complex systems. We then briefly review different modes of lubrication in synovial joints, focusing primarily on boundary lubrication. We consider modes of hydrogel lubrication and different kinds of such low-friction synthetic gels and then focus on cartilage-inspired, boundary-lubricated hydrogels. We conclude by discussing challenges and opportunities.
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Lin W, Goldberg R, Klein J. Poly-phosphocholination of liposomes leads to highly-extended retention time in mice joints. J Mater Chem B 2022; 10:2820-2827. [PMID: 35099493 PMCID: PMC9007059 DOI: 10.1039/d1tb02346b] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Surface-attached layers of phosphatidylcholine (PC) lipid vesicles (liposomes) may reduce the friction coefficient μ (= force-to-slide/load) between the sliding surfaces down to μ ≈ 10−3–10−4 up to tens of atm contact pressures, as high as those in the major joints (hips or knees). Such friction reduction is attributed to hydration lubrication by the highly-hydrated phosphocholine head-groups exposed at the outer vesicle surfaces. It has been suggested therefore that intra-articular (IA) administration of liposomes as potential boundary lubricants may alleviate degenerative, friction-associated joint conditions such as osteoarthritis (OA), which is associated with insufficient lubrication at the articular cartilage surface. To overcome the problem, common to all nanoparticles, of rapid removal by the mononuclear phagocyte system, as well as to ensure long-term colloidal stability during storage, functionalizing liposomes with poly(ethylene glycol) moieties, PEGylation, is often used. Here we describe a different liposome functionalization approach, using poly(2-methacryloyloxyethyl phosphorylcholine), PMPC, moieties (strictly, lipid–PMPC conjugates), and compare the retention time in mice joints of such PMPCylated liposomes with otherwise-identical but PEGylated vesicles following IA administration. We find, using fluorescence labeling and in vivo optical imaging, that when PMPC-stabilized liposomes are injected into mice knee joints, there is a massive increase of the vesicles’ retention half-life in the joints of about (4–5)-fold (ca. 300–400% increase in retention time) compared with the PEGylated liposomes (and some 100-fold longer than the retention time of intra-articularly injected hyaluronan or HA). Such PMPCylated liposomes are therefore promising candidates as potential long-lived boundary lubricants at the articular cartilage surface, with implication for friction-associated pathologies. Moreover, as lipid vesicles are well known to be efficient drug carriers, such long retention in the joints may enable analgesic or anti-inflammatory agents for joint pathologies to be more efficiently delivered via IA administration using PMPCylated liposomal vehicles relative to PEGylated ones. PMPCylated liposomes injected into mice joints show a massive increase in retention half-life compared with PEGylated liposomes (or hyaluronan, HA), making them promising candidates as boundary lubricants at articular cartilage, or as drug carriers.![]()
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Affiliation(s)
- Weifeng Lin
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 76100, Israel.
| | - Ronit Goldberg
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 76100, Israel.
| | - Jacob Klein
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 76100, Israel.
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10
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Rosenhek-Goldian I, Abou Karam P, Regev-Rudzki N, Rojas A. Imaging of Extracellular Vesicles Derived from Plasmodium falciparum-Infected Red Blood Cells Using Atomic Force Microscopy. Methods Mol Biol 2022; 2470:133-145. [PMID: 35881344 DOI: 10.1007/978-1-0716-2189-9_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Malaria is one the most devastating infectious diseases in the world: of the five malaria-associated parasites, Plasmodium falciparum and P. vivax are the most pathogenic and widespread, respectively. P. falciparum invades human red blood cells (RBCs), releasing extracellular vesicles (Pf-EV) carrying DNA, RNA and protein cargo components involved in host-pathogen communications in the course of the disease. Different strategies have been used to analyze Pf-EV biophysically and chemically. Atomic force microscopy (AFM) stands out as a powerful tool for rendering high quality images of extracellular vesicles. In this technique, a sharp tip attached to a cantilever reconstructs the topographic surface of the extracellular vesicles and probes their nano-mechanical properties based on force-distance curves. Here, we describe a method to separate Pf-EV using differential ultracentrifugation, followed by nanoparticle tracking analysis (NTA) to quantify and estimate the size distribution. Finally, the AFM imaging procedure on Pf-EV adsorbed on a Mg2+-modified mica surface is detailed.
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Affiliation(s)
- Irit Rosenhek-Goldian
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, Israel
| | - Paula Abou Karam
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Neta Regev-Rudzki
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Alicia Rojas
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel.
- Laboratory of Helminthology, Centro de Investigaciones en Enfermedades Tropicales, University of Costa Rica, San José, Costa Rica.
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11
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Yuan H, Cheng HW, Mears LLE, Huang R, Su R, Qi W, He Z, Valtiner M. Lipid Anchoring Improves Lubrication and Wear Resistance of the Collagen I Matrix. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:13810-13815. [PMID: 34788036 PMCID: PMC8638261 DOI: 10.1021/acs.langmuir.1c01581] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Revised: 11/06/2021] [Indexed: 05/12/2023]
Abstract
Osteoarthritis is a prevalent degenerative joint disease characterized by progressive articular cartilage loss and destruction. The resultant increase in friction causes severe pain. The collagen I matrix (COL I) has been used clinically for cartilage repair; however, how COL I acts at cartilage surfaces is unclear. Here, we studied adsorption and lubrication of synovial fluid components, albumin, γ-globulin, and the phospholipid DPPC, on COL I under physiological conditions using surface plasmon resonance and an in situ sensing surface force apparatus. Our results revealed COL I had poor lubrication ability, a fairly high coefficient of friction (COF, μ = 0.651 ± 0.013), and surface damage under a 7 mN load. DPPC formed an improved lubricating layer on COL I (μ = 0.072 ± 0.016). In sharp contrast, albumin and γ-globulin exhibited poor lubrication with an order of magnitude higher COF but still provided benefits by protecting COL I from wear. Hence, DPPC on COL I may help optimize COL I implantation design.
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Affiliation(s)
- Hui Yuan
- State
Key Laboratory of Chemical Engineering, Tianjin Key Laboratory of
Membrane Science and Desalination Technology, School of Chemical Engineering
and Technology, Tianjin University and Collaborative
Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
- Institute
of Applied Physics, Vienna University of
Technology, Vienna 1040, Austria
| | - Hsiu-Wei Cheng
- Institute
of Applied Physics, Vienna University of
Technology, Vienna 1040, Austria
| | - Laura LE Mears
- Institute
of Applied Physics, Vienna University of
Technology, Vienna 1040, Austria
| | - Renliang Huang
- School
of Marine Science and Technology, Tianjin
University, Tianjin 300072, China
| | - Rongxin Su
- State
Key Laboratory of Chemical Engineering, Tianjin Key Laboratory of
Membrane Science and Desalination Technology, School of Chemical Engineering
and Technology, Tianjin University and Collaborative
Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
| | - Wei Qi
- State
Key Laboratory of Chemical Engineering, Tianjin Key Laboratory of
Membrane Science and Desalination Technology, School of Chemical Engineering
and Technology, Tianjin University and Collaborative
Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
| | - Zhimin He
- State
Key Laboratory of Chemical Engineering, Tianjin Key Laboratory of
Membrane Science and Desalination Technology, School of Chemical Engineering
and Technology, Tianjin University and Collaborative
Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
| | - Markus Valtiner
- Institute
of Applied Physics, Vienna University of
Technology, Vienna 1040, Austria
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12
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Li Y, Yuan Z, Yang H, Zhong H, Peng W, Xie R. Recent Advances in Understanding the Role of Cartilage Lubrication in Osteoarthritis. Molecules 2021; 26:6122. [PMID: 34684706 PMCID: PMC8540456 DOI: 10.3390/molecules26206122] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 10/04/2021] [Accepted: 10/06/2021] [Indexed: 01/15/2023] Open
Abstract
The remarkable lubrication properties of normal articular cartilage play an essential role in daily life, providing almost frictionless movements of joints. Alterations of cartilage surface or degradation of biomacromolecules within synovial fluid increase the wear and tear of the cartilage and hence determining the onset of the most common joint disease, osteoarthritis (OA). The irreversible and progressive degradation of articular cartilage is the hallmark of OA. Considering the absence of effective options to treat OA, the mechanosensitivity of chondrocytes has captured attention. As the only embedded cells in cartilage, the metabolism of chondrocytes is essential in maintaining homeostasis of cartilage, which triggers motivations to understand what is behind the low friction of cartilage and develop biolubrication-based strategies to postpone or even possibly heal OA. This review firstly focuses on the mechanism of cartilage lubrication, particularly on boundary lubrication. Then the mechanotransduction (especially shear stress) of chondrocytes is discussed. The following summarizes the recent development of cartilage-inspired biolubricants to highlight the correlation between cartilage lubrication and OA. One might expect that the restoration of cartilage lubrication at the early stage of OA could potentially promote the regeneration of cartilage and reverse its pathology to cure OA.
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Affiliation(s)
- Yumei Li
- Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases, Ministry of Education, Gannan Medical University, Ganzhou 341000, China; (Y.L.); (H.Y.); (H.Z.)
- School of Basic Medicine, Gannan Medical University, Ganzhou 341000, China
| | - Zhongrun Yuan
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641, China;
- National Engineering Research Center for Tissue Restoration and Reconstruction, South China University of Technology, Guangzhou 510006, China
| | - Hui Yang
- Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases, Ministry of Education, Gannan Medical University, Ganzhou 341000, China; (Y.L.); (H.Y.); (H.Z.)
- Jiangxi Province Key Laboratory of Biomaterials and Biofabrication for Tissue Engineering, Gannan Medical University, Ganzhou 341000, China
- School of Medical Information Engineering, Gannan Medical University, Ganzhou 341000, China
| | - Haijian Zhong
- Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases, Ministry of Education, Gannan Medical University, Ganzhou 341000, China; (Y.L.); (H.Y.); (H.Z.)
- Jiangxi Province Key Laboratory of Biomaterials and Biofabrication for Tissue Engineering, Gannan Medical University, Ganzhou 341000, China
- School of Medical Information Engineering, Gannan Medical University, Ganzhou 341000, China
| | - Weijie Peng
- Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases, Ministry of Education, Gannan Medical University, Ganzhou 341000, China; (Y.L.); (H.Y.); (H.Z.)
- Jiangxi Province Key Laboratory of Biomaterials and Biofabrication for Tissue Engineering, Gannan Medical University, Ganzhou 341000, China
| | - Renjian Xie
- Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases, Ministry of Education, Gannan Medical University, Ganzhou 341000, China; (Y.L.); (H.Y.); (H.Z.)
- Jiangxi Province Key Laboratory of Biomaterials and Biofabrication for Tissue Engineering, Gannan Medical University, Ganzhou 341000, China
- School of Medical Information Engineering, Gannan Medical University, Ganzhou 341000, China
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13
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Wang H, Peng T, Wu H, Chen J, Chen M, Mei L, Li F, Wang W, Wu C, Pan X. In situ biomimetic lyotropic liquid crystal gel for full-thickness cartilage defect regeneration. J Control Release 2021; 338:623-632. [PMID: 34481927 DOI: 10.1016/j.jconrel.2021.08.062] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 08/23/2021] [Accepted: 08/31/2021] [Indexed: 12/27/2022]
Abstract
There is a great challenge in regenerating cartilage defects, which usually involve absent bearing capacity and poor adaptation to joint movement, further exacerbating subchondral bone damage. Therefore, ideal tissue-engineering cartilage scaffolds should be endowed with biomimetic and sustained-release function for promoting long-term chondrogenesis while protecting subchondral bone. Herein, in situ self-assembling gel based on glyceryl monooleate (GMO)-hyaluronic acid (HA) composite lyotropic liquid crystal (HLC) was developed as the biomimetic scaffold to deliver kartogenin for long-term cartilage regeneration. Compared to the GMO based (LLC) gel, HLC gel with modified lattice structure exhibited improved rheological properties for better joint protection by increasing mechanical strength, elasticity and lubrication. Besides, HLC gel successfully prolonged drug release and retention in the joint cavity over 4 weeks to provide combined effect of kartogenin and HA for cartilage repair. Pharmacodynamic studies demonstrated that HLC gel was the most effective to promote chondrogenesis and protect subchondral bone, making the damaged bone tissue restored to normal in divergent features as evidenced by the MRI, Micro-CT and histological results. Therefore, the HLC gel with joint protection and controlled drug release can serve as a firm scaffold for providing long-term cartilage repair.
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Affiliation(s)
- Hui Wang
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, PR China
| | - Tingting Peng
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Haofeng Wu
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, PR China
| | - Jintian Chen
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, PR China
| | - Minglong Chen
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, PR China
| | - Liling Mei
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, PR China
| | - Feng Li
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, PR China
| | - Wenhao Wang
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, PR China
| | - Chuanbin Wu
- College of Pharmacy, Jinan University, Guangzhou 510632, PR China
| | - Xin Pan
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, PR China.
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14
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Lin W, Klein J. Recent Progress in Cartilage Lubrication. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2005513. [PMID: 33759245 DOI: 10.1002/adma.202005513] [Citation(s) in RCA: 127] [Impact Index Per Article: 42.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 11/23/2020] [Indexed: 05/18/2023]
Abstract
Healthy articular cartilage, covering the ends of bones in major joints such as hips and knees, presents the most efficiently-lubricated surface known in nature, with friction coefficients as low as 0.001 up to physiologically high pressures. Such low friction is indeed essential for its well-being. It minimizes wear-and-tear and hence the cartilage degradation associated with osteoarthritis, the most common joint disease, and, by reducing shear stress on the mechanotransductive, cartilage-embedded chondrocytes (the only cell type in the cartilage), it regulates their function to maintain homeostasis. Understanding the origins of such low friction of the articular cartilage, therefore, is of major importance in order to alleviate disease symptoms, and slow or even reverse its breakdown. This progress report considers the relation between frictional behavior and the cellular mechanical environment in the cartilage, then reviews the mechanism of lubrication in the joints, in particular focusing on boundary lubrication. Following recent advances based on hydration lubrication, a proposed synergy between different molecular components of the synovial joints, acting together in enabling the low friction, has been proposed. Additionally, recent development of natural and bio-inspired lubricants is reviewed.
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Affiliation(s)
- Weifeng Lin
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Jacob Klein
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, 76100, Israel
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15
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Kosinska MK, Eichner G, Schmitz G, Liebisch G, Steinmeyer J. A comparative study on the lipidome of normal knee synovial fluid from humans and horses. PLoS One 2021; 16:e0250146. [PMID: 33861772 PMCID: PMC8051782 DOI: 10.1371/journal.pone.0250146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 03/31/2021] [Indexed: 12/02/2022] Open
Abstract
The current limitations in evaluating synovial fluid (SF) components in health and disease and between species are due in part to the lack of data on normal SF, because of low availability of SF from healthy articular joints. Our study aimed to quantify species-dependent differences in phospholipid (PL) profiles of normal knee SF obtained from equine and human donors. Knee SF was obtained during autopsy by arthrocentesis from 15 and 13 joint-healthy human and equine donors, respectively. PL species extracted from SF were quantitated by mass spectrometry whereas ELISA determined apolipoprotein (Apo) B-100. Wilcoxon’s rank sum test with adjustment of scores for tied values was applied followed by Holm´s method to account for multiple testing. Six lipid classes with 89 PL species were quantified, namely phosphatidylcholine, lysophosphatidylcholine, sphingomyelin, phosphatidylethanolamine, plasmalogen, and ceramide. Importantly, equine SF contains about half of the PL content determined in human SF with some characteristic changes in PL composition. Nutritional habits, decreased apolipoprotein levels and altered enzymatic activities may have caused the observed different PL profiles. Our study provides comprehensive quantitative data on PL species levels in normal human and equine knee SF so that research in joint diseases and articular lubrication can be facilitated.
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Affiliation(s)
- Marta K. Kosinska
- Department of Orthopaedics, Laboratory for Experimental Orthopaedics, Justus Liebig University Giessen, Giessen, Germany
| | - Gerrit Eichner
- Mathematical Institute, Justus Liebig University Giessen, Giessen, Germany
| | - Gerd Schmitz
- Institute of Clinical Chemistry and Laboratory Medicine, University Hospital Regensburg, Regensburg, Germany
| | - Gerhard Liebisch
- Institute of Clinical Chemistry and Laboratory Medicine, University Hospital Regensburg, Regensburg, Germany
| | - Jürgen Steinmeyer
- Department of Orthopaedics, Laboratory for Experimental Orthopaedics, Justus Liebig University Giessen, Giessen, Germany
- * E-mail:
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16
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Chen J, Wang H, Mei L, Wang B, Huang Y, Quan G, Lu C, Peng T, Pan X, Wu C. A pirfenidone loaded spray dressing based on lyotropic liquid crystals for deep partial thickness burn treatment: healing promotion and scar prophylaxis. J Mater Chem B 2021; 8:2573-2588. [PMID: 32147675 DOI: 10.1039/c9tb02929j] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A deep partial thickness (DPT) burn injury refers to burn damage involving the epidermis and major dermis, whose prognosis depends greatly on wound management. Lack of effective management can lead to an elongated healing process and aggravated scar formation, which can severely disturb patients, both physically and mentally. A dressing with good water absorption and moderate mechanical properties is crucial for healing promotion, and the prevention of scar formation is highly desirable. In this project, a hyaluronic acid combined lyotropic liquid crystal based spray dressing (HLCSD) loaded with the anti-fibrotic drug pirfenidone (PFD) has been designed. HLCSD is expected to achieve the goals of both wound healing promotion and scar prophylaxis. Its water absorption capacity, mechanical properties, drug release behavior and phase transition are fully evaluated. HLCSD possesses low viscosity for spray administration and high levels of water absorption for exudate absorption. An in situ gel composed of self-assembled lattice nanostructures provides excellent mechanical protection to promote the healing process and steady PFD release to exert a scar prophylaxis effect. The benefit of HLCSD on the wound healing rate is verified in vivo. In the DPT burn wound model we established, HLCSD also exhibits excellent healing promotion effects, and PFD-loaded HLCSD shows scar prophylaxis effects and displays an ideal prognosis, with skin as smooth as healthy skin. The healing promotion of HLCSD is considered to be related to the alleviation of inflammation, with an obviously shortened inflammation phase, with contributions from water management, mechanical protection and anti-inflammation by HLCSD. The scar prophylaxis of PFD-loaded HLCSD is proven to be related to the regulation of collagen synthesis and degradation, involving key cytokines like TGF-β and MMP-1. Taken together, the PFD-loaded HLCSD with healing promotion and scar prophylaxis offers significant promise as a spray dressing for DPT burn injuries.
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Affiliation(s)
- Jintian Chen
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, P. R. China.
| | - Hui Wang
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, P. R. China.
| | - Liling Mei
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, P. R. China.
| | - Bei Wang
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, P. R. China.
| | - Ying Huang
- School of Pharmacy, Jinan University, Guangzhou 510632, P. R. China.
| | - Guilan Quan
- School of Pharmacy, Jinan University, Guangzhou 510632, P. R. China.
| | - Chao Lu
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, P. R. China.
| | - Tingting Peng
- School of Pharmacy, Jinan University, Guangzhou 510632, P. R. China.
| | - Xin Pan
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, P. R. China.
| | - Chuanbin Wu
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, P. R. China. and School of Pharmacy, Jinan University, Guangzhou 510632, P. R. China.
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17
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Farias BV, Haeri F, Khan SA. Linking polymer hydrophobicity and molecular interactions to rheology and tribology in phospholipid-containing complex gels. J Colloid Interface Sci 2021; 584:134-144. [PMID: 33069013 DOI: 10.1016/j.jcis.2020.09.113] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 09/20/2020] [Accepted: 09/26/2020] [Indexed: 11/29/2022]
Abstract
HYPOTHESIS The rheological behavior and frictional properties (macroscopic level) of systems containing a hydrophobically modified polymer and phospholipids depend on the hydrophobic association that occur between the hydrophobic moiety of the polymer and the phospholipid tails (molecular level). The hydrophobicity of the polymer can thus be used to control its interactions with phospholipids, and manipulate complex gel macroscopic behavior. EXPERIMENTS By using systems composed of a crosslinked hydrophobically modified polyacrylic acid (HMPAA) or a crosslinked polyacrylic acid polymer (PAA) and phospholipids, we examine the underlying mechanisms through which the components interact using isothermal titration calorimetry (ITC) and their effect on rheological and tribological characteristics of complex gels. FINDINGS We find the systems containing HMPAA and phospholipid exhibit gel-like behavior with the elastic modulus increasing substantially upon phospholipid addition due to hydrophobic interactions that result in a more interconnected network formation, as evidenced by ITC measurements. Similar experiments with a crosslinked polyacrylic acid polymer (PAA) show no interactions, lending credence to our hypothesis. In addition, soft tribological behavior shows lower friction coefficients at low entrainment speeds with HMPAA concentration and the addition of phospholipid, while no change in friction coefficient was observed in the case of increasing PAA concentration, indicating HMPAA and phospholipids to be interacting with the soft PDMS contacts.
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Affiliation(s)
- Barbara V Farias
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, United States
| | - Farrah Haeri
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, United States
| | - Saad A Khan
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, United States.
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18
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Cao H, Xu W, Guo X. The wormlike micelles formed using an ionic liquid surfactant and polar organic solvents at low temperature without additives and their lubricant properties. SOFT MATTER 2021; 17:1437-1444. [PMID: 33326550 DOI: 10.1039/d0sm01825b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Wormlike micelles (or reverse wormlike micelles) are flexible cylindrical chains that are normally formed in water (or a nonpolar organic solvent) at 25.0 °C or above; the formation of wormlike micelles at lower temperatures is rare. Here, we have reported wormlike micelles formed at low temperature using an ionic liquid surfactant (1-octadecyl-3-nonyl imidazolium bromide) in polar organic solvents (including 1,3-propanediol, 1,2-propylene glycol, N,N-dimethylformamide, and glycerol/1,2-propylene glycol mixture) in the absence of any additives. The viscoelasticity and morphology of the wormlike micelles were studied using rheology, small-angle X-ray scattering, and cryo-transmission electron microscopy. The viscoelastic properties of the wormlike micelles in polar solvents are affected by the solvent type (or the weight ratio of glycerol to 1,2-propylene glycol), surfactant concentration, and temperature. Moreover, the G' and G'' crossover twice in the dynamic curves, which is different from the case in water. The first crossover (at low frequency) corresponds to the relaxation time for the alkyl chains to disentangle from the transient network, and the second crossover (at high frequency) is related to the segmental motion of the chains. Furthermore, the tribological performance of these wormlike micelles is investigated at low temperature. It is found that the protective film (formed by the physical adhesion of the wormlike micelles on the surface of friction disk pair) and the tribochemical reaction together lead to good antifriction and antiwear performance, which indicates the application prospects of these wormlike micelles in low-temperature lubrication.
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Affiliation(s)
- Huijiao Cao
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu 225002, P. R. China.
| | - Wenlin Xu
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu 225002, P. R. China.
| | - Xia Guo
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu 225002, P. R. China.
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19
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Angayarkanni S, Kampf N, Klein J. Lipid-Bilayer Assemblies on Polymer-Bearing Surfaces: The Nature of the Slip Plane in Asymmetric Boundary Lubrication. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:15583-15591. [PMID: 33332133 PMCID: PMC7774307 DOI: 10.1021/acs.langmuir.0c02956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 12/03/2020] [Indexed: 06/12/2023]
Abstract
Phospholipid-macromolecule complexes have been proposed to form highly efficient, lubricating boundary layers at artificial soft surfaces or at biological surfaces such as articular cartilage, where the friction reduction is attributed to the hydration lubrication mechanism acting at the exposed, hydrated head groups of the lipids. Here we measure, using a surface force balance, the normal and frictional interactions between model mica substrates across several different configurations of phosphatidylcholine (PC) lipid aggregates and adsorbed polymer (PEO) layers, to provide insight into the nature of such lubricating boundary layers in both symmetric and especially asymmetric configurations. Our results reveal that, irrespective of the configuration, the slip plane between the sliding surfaces reverts wherever possible to a bilayer-bilayer interface where hydration lubrication reduces the friction strongly. Where such an interface is not available, the sliding friction remains high. These findings may account for the low friction observed between both biological and synthetic hydrogel surfaces which may be asymmetrically coated with lipid-based boundary layers and fully support the hydration lubrication mechanism attributed to act at such boundary layers.
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Affiliation(s)
| | - Nir Kampf
- Department of Materials and
Interfaces, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Jacob Klein
- Department of Materials and
Interfaces, Weizmann Institute of Science, Rehovot 76100, Israel
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20
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Sułek MW, Bąk-Sowińska A, Przepiórka J. Ecological Cutting Fluids. MATERIALS 2020; 13:ma13245812. [PMID: 33352815 PMCID: PMC7765869 DOI: 10.3390/ma13245812] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/15/2020] [Accepted: 12/16/2020] [Indexed: 11/18/2022]
Abstract
This study deals with metalworking fluids (MWFs). According to DIN 51385, depending on their base, the fluids are divided into oil and water fluids. The oil bases include, among others, mineral, synthetic, vegetable and paraffin oils. This division does not comprise surfactant solutions which can be successfully used in metalworking. Due to the fact that this type of fluid was not qualified, a new type of lubricant based on the aqueous solutions of surfactants has been proposed. Two new notions have been introduced: surfactant working fluids (SWFs) for working fluids and surfactant lubricants (SLs) for all kinds of lubricants as a broader term. The effect of the physicochemical properties of aqueous solutions of sodium lauroyl sarcosinate (SLS), also known as sodium N-dodecanoyl-N-methyl glycinate, on tribological properties determined using a four-ball machine (Tester T-02) (Łukasiewicz Research Network—The Institute for Sustainable Technologies, Radom, Poland) was analyzed. On the basis of aqueous SLS solutions a composition of working fluids was developed and their functional properties were verified by means of tribological and stand tests as well as during operation. The test results obtained clearly indicate that functional properties of 2% solutions of sodium lauroyl sarcosinate with a foam inhibitor (0.05%) and a biocide (0.1%) are comparable to those of a quality commercial hydraulic fluid.
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Affiliation(s)
| | | | - Jacek Przepiórka
- Faculty of Chemical Engineering and Commodity Science, Kazimierz Pulaski University of Technology and Humanities in Radom, 26-600 Radom, Poland;
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21
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Feng S, Liu Y, Li J, Wang H, Wen S. Insight into the Lubrication Behavior of Phospholipids Pre-adsorbed on Silica Surfaces at Different Adsorption Temperatures. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:13477-13484. [PMID: 33136405 DOI: 10.1021/acs.langmuir.0c02192] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Phospholipids, as essential components in joint synovial fluid, play a dominant role in joint lubrication. In this study, atomic force microscopy was used to evaluate the normal and shear forces between two surfaces bearing three types of phospholipids with different acyl chain lengths, which were pre-adsorbed onto silica surfaces at different temperatures (25, 45, and 60 °C). When the pre-adsorption temperature was below the phospholipid phase transition temperature (Tm), a super-low friction coefficient [1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC): 0.002; 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC): 0.007] between two opposing silica surfaces in water was achieved because of the super-low shear strength of the hydration shell and robustness of the vesicle when the load was less than the critical value (DSPC: 500 nN; DPPC: 85 nN). However, when the pre-adsorption temperature exceeded Tm, the silica surface was covered by a bilayer structure with many defects, which exhibited poor adsorption density and low bearing capacity, resulting in a relatively high friction coefficient. This study gains insights into the influence of structure and temperature on the lubrication mechanism of phospholipids as biolubricants, providing guidance for the application of artificial joint synovial fluid.
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Affiliation(s)
- Shaofei Feng
- State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China
| | - Yuhong Liu
- State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China
| | - Jinjin Li
- State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China
| | - Hongdong Wang
- State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China
| | - Shizhu Wen
- State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China
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22
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Affiliation(s)
- Irit Rosenhek‐Goldian
- Department of Chemical Research Support Weizmann Institute of Science Herzl 234 Rehovot ISRAEL
| | - Sidney R. Cohen
- Department of Chemical Research Support Weizmann Institute of Science Herzl 234 Rehovot ISRAEL
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23
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Lin W, Kluzek M, Iuster N, Shimoni E, Kampf N, Goldberg R, Klein J. Cartilage-inspired, lipid-based boundary-lubricated hydrogels. Science 2020; 370:335-338. [DOI: 10.1126/science.aay8276] [Citation(s) in RCA: 82] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 05/10/2020] [Accepted: 08/06/2020] [Indexed: 12/17/2022]
Abstract
The lubrication of hydrogels arises from fluid or solvated surface
phases. By contrast, the lubricity of articular cartilage, a complex
biohydrogel, has been at least partially attributed to nonfluid,
lipid-exposing boundary layers. We emulated this behavior in synthetic
hydrogels by incorporating trace lipid concentrations to create a
molecularly thin, lipid-based boundary layer that renews continuously. We
observed a 80% to 99.3% reduction in friction and wear relative to the
lipid-free gel, over a wide range of conditions. This effect persists when
the gels are dried and then rehydrated. Our approach may provide a method
for sustained, extreme lubrication of hydrogels in applications from tissue
engineering to clinical diagnostics.
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Affiliation(s)
- Weifeng Lin
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Monika Kluzek
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Noa Iuster
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Eyal Shimoni
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Nir Kampf
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Ronit Goldberg
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Jacob Klein
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot 76100, Israel
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24
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Liu Z, Lin W, Fan Y, Kampf N, Wang Y, Klein J. Effects of Hyaluronan Molecular Weight on the Lubrication of Cartilage-Emulating Boundary Layers. Biomacromolecules 2020; 21:4345-4354. [PMID: 32931261 PMCID: PMC7556541 DOI: 10.1021/acs.biomac.0c01151] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
![]()
Osteoarthritic
joints contain lower-molecular-weight (MW) hyaluronan
(hyaluronic acid, HA) than healthy joints. To understand the relevance
of this HA size effect for joint lubrication, the friction and surface
structure of cartilage-emulating surfaces with HA of different MWs
were studied using a surface force balance (SFB) and atomic force
microscopy (AFM). Gelatin (gel)-covered mica surfaces were coated
with high-MW HA (HHA), medium-MW HA (MHA), or low-MW HA (LHA), and
lipids of hydrogenated soy l-α-phosphatidylcholine
(HSPC) in the form of small unilamellar vesicles, using a layer-by-layer
assembly method. SFB results indicate that the gel-HHA-HSPC boundary
layer provides very efficient lubrication, attributed to hydration
lubrication at the phosphocholine headgroups exposed by the HA-attached
lipids, with friction coefficients (COF) as low as 10–3–10–4 at contact stresses at least up to P = 120 atm. However, for the gel-MHA-HSPC and gel-LHA-HSPC
surfaces, the friction, initially low, increases sharply at much lower
pressures (up to 30–60 atm at most). This higher friction with
the shorter chains may be due to their weaker total adhesion energy
to the gelatin, where the attraction between the negatively charged
HA and the weakly positively charged gelatin is attributed largely
to counterion-release entropy. Thus, the complexes of LHA and MHA
with the lubricating HSPC lipids are more easily removed by shear
during sliding, especially at high stresses, than the HHA-HSPC complex,
which is strongly adhered to gelatin. This is ultimately the reason
for lower-pressure lubrication breakdown with the shorter polysaccharides.
Our results provide molecular-level insight into why the decrease
in HA molecular weight in osteoarthritic joints may be associated
with higher friction at the articular cartilage surface, and may have
relevance for treatments of osteoarthritis involving intra-articular
HA injections.
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Affiliation(s)
- Zhang Liu
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot 76100, Israel.,Key Laboratory of Colloid and Interface Science, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Weifeng Lin
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yaxun Fan
- Key Laboratory of Colloid and Interface Science, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Nir Kampf
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yilin Wang
- Key Laboratory of Colloid and Interface Science, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Jacob Klein
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot 76100, Israel
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25
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The Role of Hyaluronic Acid in Cartilage Boundary Lubrication. Cells 2020; 9:cells9071606. [PMID: 32630823 PMCID: PMC7407873 DOI: 10.3390/cells9071606] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Revised: 06/27/2020] [Accepted: 06/30/2020] [Indexed: 01/23/2023] Open
Abstract
Hydration lubrication has emerged as a new paradigm for lubrication in aqueous and biological media, accounting especially for the extremely low friction (friction coefficients down to 0.001) of articular cartilage lubrication in joints. Among the ensemble of molecules acting in the joint, phosphatidylcholine (PC) lipids have been proposed as the key molecules forming, in a complex with other molecules including hyaluronic acid (HA), a robust layer on the outer surface of the cartilage. HA, ubiquitous in synovial joints, is not in itself a good boundary lubricant, but binds the PC lipids at the cartilage surface; these, in turn, massively reduce the friction via hydration lubrication at their exposed, highly hydrated phosphocholine headgroups. An important unresolved issue in this scenario is why the free HA molecules in the synovial fluid do not suppress the lubricity by adsorbing simultaneously to the opposing lipid layers, i.e., forming an adhesive, dissipative bridge between them, as they slide past each other during joint articulation. To address this question, we directly examined the friction between two hydrogenated soy PC (HSPC) lipid layers (in the form of liposomes) immersed in HA solution or two palmitoyl-oleoyl PC (POPC) lipid layers across HA-POPC solution using a surface force balance (SFB). The results show, clearly and surprisingly, that HA addition does not affect the outstanding lubrication provided by the PC lipid layers. A possible mechanism indicated by our data that may account for this is that multiple lipid layers form on each cartilage surface, so that the slip plane may move from the midplane between the opposing surfaces, which is bridged by the HA, to an HA-free interface within a multilayer, where hydration lubrication is freely active. Another possibility suggested by our model experiments is that lipids in synovial fluid may complex with HA, thereby inhibiting the HA molecules from adhering to the lipids on the cartilage surfaces.
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Lin W, Kampf N, Klein J. Designer Nanoparticles as Robust Superlubrication Vectors. ACS NANO 2020; 14:7008-7017. [PMID: 32412738 PMCID: PMC7315629 DOI: 10.1021/acsnano.0c01559] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Accepted: 05/15/2020] [Indexed: 05/25/2023]
Abstract
Phosphatidylcholine lipid bilayers or liposomes at interfaces in aqueous environments can provide extremely efficient lubrication. This is attributed to the hydration lubrication mechanism acting at the highly hydrated phosphocholine-headgroup layers exposed at the outer surface of each bilayer. Micelles exposing such phosphocholine groups could be an attractive alternative to liposomes due to their much easier preparation and structure control, but all studies to date of surfactant micelles have revealed that at relatively low normal stresses the surface layers rupture and friction increases abruptly. Here, we examine surface interactions between three kinds of phosphocholine-exposing micelles with different designed structures: single-tail surfactant micelles, homo-oligomeric micelles, and block copolymer micelles. Normal and shear forces between mica surfaces immersed in solutions of these micelles were measured using a surface force balance. The adsorbed layers on the mica were imaged using atomic force microscope, revealing surface structures ranging from wormlike to spherical micelles. The block copolymer micelles showed relatively low coverage arising from their stabilizing corona and consequently poor lubrication (μ ∼ 10-1). In contrast, the surfactant and homo-oligomeric micelles fully covered the mica surface and demonstrated excellent lubrication (μ ∼ O(10-3)). However, while the boundary layer of single-tailed surfactant micelles degraded under moderate pressure, the homo-oligomeric micellar boundary layer was robust at all applied contact pressures in our study (up to about 5 MPa). We attribute the difference to the much greater energy required to remove a homo-oligomeric molecule from its micelle, resulting in far greater stability under pressure and shear.
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Affiliation(s)
- Weifeng Lin
- Department
of Materials and Interfaces, Weizmann Institute
of Science, Rehovot 76100, Israel
| | - Nir Kampf
- Department
of Materials and Interfaces, Weizmann Institute
of Science, Rehovot 76100, Israel
| | - Jacob Klein
- Department
of Materials and Interfaces, Weizmann Institute
of Science, Rehovot 76100, Israel
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Cao Y, Kampf N, Lin W, Klein J. Normal and shear forces between boundary sphingomyelin layers under aqueous conditions. SOFT MATTER 2020; 16:3973-3980. [PMID: 32250380 DOI: 10.1039/d0sm00215a] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Sphingomyelin is one of the predominant phospholipid groups in synovial joints, where lipids have been strongly implicated in the boundary lubrication of articular cartilage; however, little attention has been paid to its lubrication behavior. In this study, we demonstrate that sphingomyelin is an excellent boundary lubricant by measuring the normal and shear forces between sphingomyelin-layer-coated surfaces with a surface force balance under aqueous conditions. Slightly negatively-charged egg sphingomyelin vesicles were adsorbed on mica either by calcium bridging or by charge screening with high concentration monovalent salt. The normal force profiles between opposing egg sphingomyelin layers (vesicles or bilayers) show long-ranged weak repulsion and short-ranged strong repulsion on approaching. Friction coefficients, calculated from the highest load, were (7.2 ± 1.7) × 10-4 at contact stresses of 9.1 ± 0.7 MPa across 0.3 mM liposome dispersion in 0.03 mM Ca2+, and (0.8-3.5) × 10-3 at contact stresses of 7.6 ± 0.8 MPa across 0.3 mM liposome dispersion in 150 mM NaNO3. Similar or slightly lower friction coefficients of (5.3 ± 0.8) × 10-4 at 9.8 ± 0.2 MPa were obtained by replacing the liposome dispersion in 0.03 mM Ca2+ by water. Such low friction coefficients, attributed to the hydration lubrication mechanism, are comparable to those of phosphatidylcholine lipids, which have been widely recognized as excellent aqueous biolubricants. Therefore, we believe that sphingomyelin, in parallel with phosphatidylcholine, contributes to the remarkably good boundary lubrication in synovial joints.
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Affiliation(s)
- Yifeng Cao
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, 76100, Israel.
| | - Nir Kampf
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, 76100, Israel.
| | - Weifeng Lin
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, 76100, Israel.
| | - Jacob Klein
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, 76100, Israel.
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Ji X, Yan Y, Sun T, Zhang Q, Wang Y, Zhang M, Zhang H, Zhao X. Glucosamine sulphate-loaded distearoyl phosphocholine liposomes for osteoarthritis treatment: combination of sustained drug release and improved lubrication. Biomater Sci 2019; 7:2716-2728. [PMID: 31033977 DOI: 10.1039/c9bm00201d] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Osteoarthritis (OA) is a chronic joint disease resulting from joint inflammation and damage. In this study, we employed a boundary lubricant known as a 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) liposome for loading of an anti-inflammatory drug d-glucosamine sulphate (GAS) to construct a treatment strategy allowing for sustained anti-inflammation and reduced damage. This kind of drug-loaded nanocarrier integrates the anti-inflammatory effect of the GAS and the lubrication ability of DSPC liposomes without the involvement of complex synthesis processes leading to easier popularization. Our experimental results indicated that the GAS-loaded DSPC liposomes could release GAS in a sustained manner while providing good lubrication in pure water (H2O) and phosphate buffered saline (PBS). Moreover, the GAS-loaded DSPC liposomes prepared at a 2 : 8 molar ratio in PBS exhibited a greater entrapment efficiency, lower GAS release rate and smaller friction coefficient as compared to those prepared in H2O. The superiority of the drug release and lubrication ability achieved with the GAS-loaded DSPC liposomes in PBS were elucidated on the basis of salt-induced enhancement in liposomal stability and hydration lubrication by the hydrated salt ions. Such GAS release accelerated the viability and proliferation of primary mouse chondrocytes while also providing the anti-inflammatory and chondroprotective potential for tumor necrosis factor (TNF-α) induced chondrocyte degeneration through the down-regulation of pro-inflammatory cytokines, pain related gene and catabolic proteases, as well as the up-regulation of anabolic components. We envision that the GAS-loaded DSPC liposomes could represent a promising new strategy for clinical treatment of OA in the future.
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Affiliation(s)
- Xiuling Ji
- State Key Laboratory of Tribology, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China.
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Cao Y, Kampf N, Klein J. Boundary Lubrication, Hemifusion, and Self-Healing of Binary Saturated and Monounsaturated Phosphatidylcholine Mixtures ⧫. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:15459-15468. [PMID: 31296001 DOI: 10.1021/acs.langmuir.9b01660] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A wide range of phosphatidylcholine (PC) lipids with different degrees of unsaturation has been identified in the human synovial fluid and on the cartilage surface. The outstanding lubricity of the articular cartilage surface has been attributed to boundary layers comprising complexes of such lipids, though to date, only lubrication by single-component PC-lipid-based boundary layers has been investigated. As distinguishable lubrication behavior has been found to be related to the PC structures, we herein examined the surface morphology (on mica) and the lubrication ability of binary PC lipid mixtures, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), using atomic force microscopy (AFM) and a surface force balance (SFB). These two PC lipids are among the most abundant saturated and unsaturated PC components in synovial joints. Small unilamellar vesicles (SUVs) prepared from DPPC-POPC mixtures (8:2, 5:5, and 2:8, molar ratios) ruptured and formed bilayers on mica. The normal and shear forces between two DPPC-POPC bilayer-coated mica surfaces across the corresponding SUV dispersions show good boundary lubrication (friction coefficients ≤ ca. 10-4) up to contact stresses of 8.3 ± 2.2 MPa for 8:2 DPPC-POPC and 5.0 ± 1.7 MPa for the others. Hemifusion induced at high normal pressures was observed, probably because of the height mismatch of two components. Reproducible successive approaches after hemifusion indicate rapid self-healing of the mica-supported bilayers in the presence of the SUVs reservoir. This work is a first step to provide insight concerning the lubrication, wear, and healing of the PC-based boundary layers, which must consist of multicomponent lipid mixtures, on the articular cartilage surface.
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Affiliation(s)
- Yifeng Cao
- Department of Materials and Interfaces , Weizmann Institute of Science , Rehovot 76100 , Israel
| | - Nir Kampf
- Department of Materials and Interfaces , Weizmann Institute of Science , Rehovot 76100 , Israel
| | - Jacob Klein
- Department of Materials and Interfaces , Weizmann Institute of Science , Rehovot 76100 , Israel
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Angayarkanni SA, Kampf N, Klein J. Surface Interactions between Boundary Layers of Poly(ethylene oxide)-Liposome Complexes: Lubrication, Bridging, and Selective Ligation †. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:15469-15480. [PMID: 31348857 DOI: 10.1021/acs.langmuir.9b01708] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Poly(ethylene oxide), PEO, is widely exploited in biomedical applications, while phosphatidylcholine (PC) lipids (in the form of bilayers or liposomes) have been identified as very efficient boundary lubricants in aqueous media. Here we examine, using a surface force balance (SFB), the interactions between surface-adsorbed layers of PEO complexed with small unilamellar vesicles (SUVs, i.e. liposomes) or with bilayers of PC lipids, both well below and a little above their main gel-to-liquid phase-transition temperatures TM. The morphology of PEO layers (adsorbed onto mica), to which liposomes were added, was examined using atomic force microscopy (AFM) and cryo-scanning electron microscopy (cryo-SEM). Our results reveal that the PC lipids could attach to the PEO either as vesicles or as bilayers, depending on whether they were above or below TM. Under water (no added salt), excellent lubrication, with friction coefficients down to 10-3-10-4, up to contact stresses of 6.5 MPa (comparable to those in the major joints) was observed between two surfaces bearing such PEO-PC complexes. At 0.1 M KNO3 salt concentration (comparable to physiological salt levels), the friction between such surfaces was considerably higher, attributed to bridging by the polymer chains. Remarkably, such bridging could be suppressed and the friction could be restored to its previous low value if the KNO3 was replaced with NaNO3, as a result of the different PEO-mica ligation properties of Na+ compared to those of K+. Our results provide insight into the properties of PEO-PC complexes in potential applications, and large interfacial effects that can result from the seemingly innocuous replacement of K+ by Na+ ions.
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Affiliation(s)
- S A Angayarkanni
- Department of Materials and Interfaces , Weizmann Institute of Science , Rehovot 76100 , Israel
| | - Nir Kampf
- Department of Materials and Interfaces , Weizmann Institute of Science , Rehovot 76100 , Israel
| | - Jacob Klein
- Department of Materials and Interfaces , Weizmann Institute of Science , Rehovot 76100 , Israel
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31
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Lin W, Klein J. Control of surface forces through hydrated boundary layers. Curr Opin Colloid Interface Sci 2019. [DOI: 10.1016/j.cocis.2019.10.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Biolubrication synergy: Hyaluronan - Phospholipid interactions at interfaces. Adv Colloid Interface Sci 2019; 274:102050. [PMID: 31669714 DOI: 10.1016/j.cis.2019.102050] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 10/15/2019] [Accepted: 10/16/2019] [Indexed: 11/24/2022]
Abstract
The manner in which nature has solved lubrication issues has fascinated scientists for centuries, in particular when considering that lubrication is achieved in aqueous media. The most outstanding system in this respect is likely the synovial joint, where close to frictionless motion is realized under different loads and shear rates. This review article focuses on two components present in the synovial area, hyaluronan and phospholipids. We recapitulate what has been learned about their interactions at interfaces from recent experiments, with focus on results obtained using reflectivity techniques at large scale facilities. In parallel, modelling experiments have been carried out and from these efforts new detailed knowledge about how hyaluronan and phospholipids interact has been gained. In this review we combine findings from modelling and experiments to gain deeper insight. Finally, we summarize what has been learned of the lubrication performance of mixtures of phospholipids and hyaluronan.
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Li J, Li J, Jiang L, Chen X, Luo J. Cationic Surfactant Micelles Lubricate Graphitic Surface in Water. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:11108-11113. [PMID: 31364855 DOI: 10.1021/acs.langmuir.9b01804] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
It is easy to achieve extremely low friction of graphene or graphite in dry conditions via the formation of an incommensurate interface but is difficult to achieve with water lubrication. Herein, we propose a new strategy to achieve extremely low friction on a graphitic surface in water by self-assembling cationic surfactant micelles in the contact zone. When uniform surfactant micelles are formed on silica and freshly cleaved graphene layers via self-assembly under low contact pressure, the friction coefficient between them can reduce to 0.0004. When the self-assembled micelles are ruptured in the contact zone by high pressure, the friction coefficient between them would increase to 0.005 (still in the superlubricity regime). The mechanism of the different friction behaviors was studied at the nanoscale, which was attributed to the formation of different shear planes that shifts from the interface of the micelle/micelle to surfactant molecules/graphene layers after micellar rupture. The results provide direct evidence that the cationic surfactant micelles can efficiently lubricate graphitic surface regardless of micellar rupture.
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Affiliation(s)
- Jinjin Li
- State Key Laboratory of Tribology , Tsinghua University , Beijing 100084 , China
| | - Jianfeng Li
- State Key Laboratory of Tribology , Tsinghua University , Beijing 100084 , China
| | - Liang Jiang
- Tribology Research Institute, State Key Laboratory of Traction Power , Southwest Jiaotong University , Chengdu 610031 , China
| | - Xinchun Chen
- State Key Laboratory of Tribology , Tsinghua University , Beijing 100084 , China
| | - Jianbin Luo
- State Key Laboratory of Tribology , Tsinghua University , Beijing 100084 , China
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Lin W, Kampf N, Goldberg R, Driver MJ, Klein J. Poly-phosphocholinated Liposomes Form Stable Superlubrication Vectors. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:6048-6054. [PMID: 30991806 DOI: 10.1021/acs.langmuir.9b00610] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
We have prepared phosphatidylcholine (PC) vesicles (liposomes) incorporating a novel lipid/poly-phosphocholine conjugate. This both stabilizes the liposomes against aggregation (for example, during storage or when being delivered) and allows them to act as very efficient lubricating elements readily attaining superlubric performance (defined as coefficient of friction μ < 10-2) via hydration lubrication at physiological salt concentrations and pressures. In contrast, vesicles sterically protected by poly(ethylene glycol) chains (PEGylation), which is the general method of choice, while being equally stable to aggregation are much poorer lubricants under these conditions, which is attributed to the relatively poor hydration of the PEG. Our approach enables the use of PC liposomes as stable superlubrication vectors in potential biomedical applications.
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Affiliation(s)
- Weifeng Lin
- Department of Materials and Interfaces , Weizmann Institute of Science , Rehovot 76100 , Israel
| | - Nir Kampf
- Department of Materials and Interfaces , Weizmann Institute of Science , Rehovot 76100 , Israel
| | - Ronit Goldberg
- Department of Materials and Interfaces , Weizmann Institute of Science , Rehovot 76100 , Israel
| | - Michael J Driver
- Vertellus Biomaterials , Vertellus Specialties UK Ltd. , Basingstoke , Hampshire RG25 2PH , United Kingdom
| | - Jacob Klein
- Department of Materials and Interfaces , Weizmann Institute of Science , Rehovot 76100 , Israel
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35
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Investigation of the lubrication properties and synergistic interaction of biocompatible liposome-polymer complexes applicable to artificial joints. Colloids Surf B Biointerfaces 2019; 178:469-478. [PMID: 30925370 DOI: 10.1016/j.colsurfb.2019.03.041] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Revised: 03/12/2019] [Accepted: 03/18/2019] [Indexed: 02/07/2023]
Abstract
Achievement of efficient biolubrication is essential for the design of artificial joints with long lifetimes. This study examines the frictional behaviors and adsorption structures of liposomes and liposome complexes with biocompatible polymers to reveal the underlying lubrication mechanisms between biomimetic bearing surfaces of polyetheretherketone (PEEK) and silicon nitride (Si3N4). The liposomes with increasing carbon chain lengths exhibit the remarkable lubrication capabilities that correlate strongly with the structural integrity of small unilamellar vesicles adsorbed on the Si3N4 surfaces, while the bilayer structures weaken the stability of vesicles against rupture and cause the increase of friction. The synergistic interaction of liposomes and biocompatible negative-charged polymer leads to the formation of a boundary-lubricating layer with high-density liposome-polymer complex structures that can efficiently improve the lubrication properties of liposomes. Our findings might have implications for future biolubrication investigations on biocompatible liposome-polymer complexes applicable to artificial joints at the specified macroscale conditions.
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Rosenhek-Goldian I, Kampf N, Klein J. Trapped Aqueous Films Lubricate Highly Hydrophobic Surfaces. ACS NANO 2018; 12:10075-10083. [PMID: 30252440 DOI: 10.1021/acsnano.8b04735] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Friction at hydrophobic surfaces in aqueous media is ubiquitous ( e.g., prosthetic implants, contact lenses, microfluidic devices, biological tissue) but is not well understood. Here, we measure directly, using a surface force balance, both normal stresses and sliding friction in an aqueous environment between a hydrophilic surface (single-crystal mica) and the stable, molecularly smooth, highly hydrophobic surface of a spin-cast fluoropolymer film. Normal force versus surface separation profiles indicate a high negative charge density at the water-immersed fluoropolymer surface, consistent with previous studies. Sliding of the compressed surfaces under water or in physiological-level salt solution (0.1 M NaCl) reveals strikingly low boundary friction (friction coefficient μ ≈ 0.003-0.009) up to contact pressures of at least 50 atm. This is attributed largely to hydrated counterions (protons and Na+ ions) trapped in thin interfacial films between the compressed, sliding surfaces. Our results reveal how frictional dissipation may occur at hydrophobic surfaces in water and how modification of such surfaces may suppress this dissipation.
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Affiliation(s)
- Irit Rosenhek-Goldian
- Department of Materials and Interfaces , Weizmann Institute of Science , Rehovot 76100 , Israel
| | - Nir Kampf
- Department of Materials and Interfaces , Weizmann Institute of Science , Rehovot 76100 , Israel
| | - Jacob Klein
- Department of Materials and Interfaces , Weizmann Institute of Science , Rehovot 76100 , Israel
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37
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Xu X, Billing M, Ruths M, Klok HA, Yu J. Structure and Functionality of Polyelectrolyte Brushes: A Surface Force Perspective. Chem Asian J 2018; 13:3411-3436. [PMID: 30080310 DOI: 10.1002/asia.201800920] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Indexed: 11/11/2022]
Abstract
The unique functionality of polyelectrolyte brushes depends on several types of specific interactions, including solvent structure effects, hydrophobic forces, electrostatic interactions, and specific ion interactions. Subtle variations in the solution environment can lead to conformational and surface structural changes of the polyelectrolyte brushes, which are mainly discussed from a surface-interaction perspective in this Focus Review. A brief overview is given of recent theoretical and experimental progress in the structure of polyelectrolyte brushes in various environments. Two important techniques for surface-force measurements are described, the surface forces apparatus (SFA) and atomic force microscopy (AFM), and some recent results on polyelectrolyte brushes are shown. Lastly, this Focus Review highlights the use of these surface-grafted polyelectrolyte brushes in the creation of functional surfaces for various applications, including nonfouling surfaces, boundary lubricants, and stimuli-responsive surfaces.
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Affiliation(s)
- Xin Xu
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore.,Department of Chemistry, University of Massachusetts Lowell, Lowell, MA, 01854, USA
| | - Mark Billing
- Institut des Matériaux et Institut des Sciences et Ingénierie Chimiques, Laboratoire des Polymères, École Polytechnique Fédérale de Lausanne (EPFL), Bâtiment MXD, Station 12, CH-1015, Lausanne, Switzerland
| | - Marina Ruths
- Department of Chemistry, University of Massachusetts Lowell, Lowell, MA, 01854, USA
| | - Harm-Anton Klok
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore.,Institut des Matériaux et Institut des Sciences et Ingénierie Chimiques, Laboratoire des Polymères, École Polytechnique Fédérale de Lausanne (EPFL), Bâtiment MXD, Station 12, CH-1015, Lausanne, Switzerland
| | - Jing Yu
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore
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Cooper BG, Catalina Bordeianu, Nazarian A, Snyder BD, Grinstaff MW. Active agents, biomaterials, and technologies to improve biolubrication and strengthen soft tissues. Biomaterials 2018; 181:210-226. [PMID: 30092370 PMCID: PMC6766080 DOI: 10.1016/j.biomaterials.2018.07.040] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Revised: 07/22/2018] [Accepted: 07/25/2018] [Indexed: 12/27/2022]
Abstract
Normal functioning of articulating tissues is required for many physiological processes occurring across length scales from the molecular to whole organism. Lubricating biopolymers are present natively on tissue surfaces at various sites of biological articulation, including eyelid, mouth, and synovial joints. The range of operating conditions at these disparate interfaces yields a variety of tribological mechanisms through which compressive and shear forces are dissipated to protect tissues from material wear and fatigue. This review focuses on recent advances in active agents and biomaterials for therapeutic augmentation of friction, lubrication, and wear in disease and injured states. Various small-molecule, biological, and gene delivery therapies are described, as are tribosupplementation with naturally-occurring and synthetic biolubricants and polymer reinforcements. While reintroduction of a diseased tissue's native lubricant received significant attention in the past, recent discoveries and pre-clinical research are capitalizing on concurrent advances in the molecular sciences and bioengineering fields, with an understanding of the underlying tissue structure and physiology, to afford a desired, and potentially patient-specific, tissue mechanical response for restoration of normal function. Small and large molecule drugs targeting recently elucidated pathways as well as synthetic and hybrid natural/synthetic biomaterials for restoring a desired tissue mechanical response are being investigated for treatment of, for example, keratoconjunctivitis sicca, xeroderma, and osteoarthritis.
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Affiliation(s)
- Benjamin G Cooper
- Department of Chemistry, Boston University, Boston, MA, United States; Center for Advanced Orthopaedic Studies, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States.
| | - Catalina Bordeianu
- Department of Chemistry, Boston University, Boston, MA, United States; Department of Biomedical Engineering, Boston University, Boston, MA, United States.
| | - Ara Nazarian
- Center for Advanced Orthopaedic Studies, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States.
| | - Brian D Snyder
- Center for Advanced Orthopaedic Studies, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States; Department of Biomedical Engineering, Boston University, Boston, MA, United States; Department of Orthopaedic Surgery, Boston Children's Hospital, Boston, MA, United States.
| | - Mark W Grinstaff
- Department of Chemistry, Boston University, Boston, MA, United States; Department of Biomedical Engineering, Boston University, Boston, MA, United States; Department of Medicine, Boston University, Boston, MA, United States.
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39
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Duan Y, Liu Y, Li J, Wang H, Wen S. Investigation on the Nanomechanics of Liposome Adsorption on Titanium Alloys: Temperature and Loading Effects. Polymers (Basel) 2018; 10:polym10040383. [PMID: 30966418 PMCID: PMC6415199 DOI: 10.3390/polym10040383] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 03/27/2018] [Accepted: 03/29/2018] [Indexed: 01/08/2023] Open
Abstract
The mechanical properties of liposomes, determined by the lipid phase state at ambient temperature, have a close relationship with their physiological activities. Here, atomic force microscopy (AFM) was used to produce images and perform force measurements on titanium alloys at two adsorbed temperatures. The mechanical properties were evaluated under repeated loading and unloading, suggesting a better reversibility and resistance of gel phase liposomes. The liquid phase liposomes were irreversibly damaged during the first approach while the gel phase liposomes could bear more iterations, resulting from water flow reversibly going across the membranes. The statistical data offered strong evidence that the lipid membranes in the gel phase are robust enough to resist the tip penetration, mainly due to their orderly organization and strong hydrophobic interactions between lipid molecules. This work regarding the mechanical properties of liposomes with different phases provides guidance for future clinical applications, such as artificial joints.
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Affiliation(s)
- Yiqin Duan
- State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China.
| | - Yuhong Liu
- State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China.
| | - Jinjin Li
- State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China.
| | - Hongdong Wang
- State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China.
| | - Shizhu Wen
- State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China.
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Abstract
Introduction Pre-clinical testing of hemiarthroplasty devices requires that the tribological conditions present in vivo with live cartilage be closely duplicated. A current limitation in the tribological testing of live cartilage involves the use of cell-culture media as lubricant. Study Aim to develop and test a new hyaluronan-phospholipid based medium (HA-phospholipid medium) that combines the rheological and frictional properties of synovial fluid with the nourishing properties of culture media to keep cells alive. Materials and Methods The HA-phospholipid medium consisted of culture medium with added phospholipid dipalmitoylphosphatidylcholine (0.3 mg/mL), and hyaluronic acid (2.42 mg/mL). A standard cell culture medium was used as the control. The rheology of each medium was determined using a flat plate configuration. Bovine calf cartilage was used to assess cell viability and friction in each medium. For friction measurements, a cobalt-chrome alloy ball was articulated against cartilage disks immersed in medium. Results Lipid vesicles 0.1 to 50 μm in diameter were identified in the HA-phospholipid medium. Cartilage cell viability was significantly higher in the HA-phospholipid medium (62% ± 8%, 95% CI) than in control medium (49.5% ± 5%) (p = 0.009). The HA-phospholipid medium exhibited strong shear-thinning behavior, similar to synovial fluid, with viscosities ~100-fold higher at 10 s-1 and 5-fold higher at 20,000 s-1 than the approximately Newtonian control medium. The HA-phospholipid medium also yielded 20% lower friction values than the control medium after one hour of testing. Conclusions The rheological and friction results indicate that the HA-phospholipid medium is superior to the control cell culture medium in emulating the shear thinning and lubricative properties of natural synovial fluid, making it more clinically relevant for in vitro wear and friction testing with live cartilage.
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Bartenstein JE, Liu X, Lange K, Claesson PM, Briscoe WH. Polymersomes at the solid-liquid interface: Dynamic morphological transformation and lubrication. J Colloid Interface Sci 2017; 512:260-271. [PMID: 29073467 DOI: 10.1016/j.jcis.2017.10.065] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 10/13/2017] [Accepted: 10/16/2017] [Indexed: 10/18/2022]
Abstract
Polymersomes are hollow spheres self-assembled from amphiphilic block copolymers of certain molecular architecture. Whilst they have been widely studied for biomedical applications, relatively few studies have reported their interfacial properties. In particular, lubrication by polymersomes has not been previously reported. Here, interfacial properties of polymersomes self-assembled from poly(butadiene)-poly(ethylene oxide) (PBD-PEO; molecular weight 10,400 g mol-1) have been studied at both hydrophilic and hydrophobic surfaces. Their morphology at silica and mica surfaces was imaged with quantitative nanomechanical property mapping atomic force microscopy (QNM AFM), and friction and surface forces they mediate under confinement between two surfaces were studied using colloidal probe AFM (CP-AFM). We find that the polymersomes remained intact but adopted flattened conformation once adsorbed to mica, with a relatively low coverage. However, on silica these polymersomes were unstable, rupturing to form donut shaped residues or patchy bilayers. On a silica surface hydrophobized with a 19 nm polystyrene (PS) film, the polymer vesicles formed a more stable layer with a higher surface coverage as compared to the hydrophilic surface, and the interfacial structure also evolved over time. Moreover, friction was greatly reduced on hydrophobized silica surfaces in the presence of polymersomes, suggesting their potential as effective aqueous lubricants.
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Affiliation(s)
- Julia E Bartenstein
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, UK
| | - Xiaoyan Liu
- Surface and Corrosion Science, Drottning Kristinas Väg 51, Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Kathrin Lange
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, UK
| | - Per M Claesson
- Surface and Corrosion Science, Drottning Kristinas Väg 51, Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Wuge H Briscoe
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, UK.
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Abstract
The major synovial joints such as hips and knees are uniquely efficient tribological systems, able to articulate over a wide range of shear rates with a friction coefficient between the sliding cartilage surfaces as low as 0.001 up to pressures of more than 100 atm. No human-made material can match this. The means by which such surfaces maintain their very low friction has been intensively studied for decades and has been attributed to fluid-film and boundary lubrication. Here, we focus especially on the latter: the reduction of friction by molecular layers at the sliding cartilage surfaces. In particular, we discuss such lubrication in the light of very recent advances in our understanding of boundary effects in aqueous media based on the paradigms of hydration lubrication and of the synergism between different molecular components of the synovial joints (namely hyaluronan, lubricin, and phospholipids) in enabling this lubrication.
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Affiliation(s)
- Sabrina Jahn
- Weizmann Institute of Science, Rehovot 76100, Israel;
| | - Jasmine Seror
- Weizmann Institute of Science, Rehovot 76100, Israel;
| | - Jacob Klein
- Weizmann Institute of Science, Rehovot 76100, Israel;
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43
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Ultra-low friction between boundary layers of hyaluronan-phosphatidylcholine complexes. Acta Biomater 2017; 59:283-292. [PMID: 28669720 DOI: 10.1016/j.actbio.2017.06.043] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 06/27/2017] [Accepted: 06/28/2017] [Indexed: 11/21/2022]
Abstract
The boundary layers coating articular cartilage in synovial joints constitute unique biomaterials, providing lubricity at levels unmatched by any human-made materials. The underlying molecular mechanism of this lubricity, essential to joint function, is not well understood. Here we study the interactions between surfaces bearing attached hyaluronan (hyaluronic acid, or HA) to which different phosphatidylcholine (PC) lipids had been added, in the form of small unilamellar vesicles (SUVs or liposomes), using a surface force balance, to shed light on possible cartilage boundary lubrication by such complexes. Surface-attached HA was complexed with different PC lipids (hydrogenated soy PC (HSPC), 1,2-dimyristoyl-sn-glycero-3-PC (DMPC) and 1-palmitoyl-2-oleoyl-sn-glycero-3-PC (POPC)), followed by rinsing. Atomic force microscopy (AFM) and cryo-scanning electron microscopy (Cryo-SEM) were used to image the HA-PC surface complexes following addition of the SUVs. HA-HSPC complexes provide very efficient lubrication, with friction coefficients as low as μ∼0.001 at physiological pressures P≈150atm, while HA-DMPC and HA-POPC complexes are efficient only at low P (up to 10-20atm). The friction reduction in all cases is attributed to hydration lubrication by highly-hydrated phosphocholine groups exposed by the PC-HA complexes. The greater robustness at high P of the HSPC (C16(15%),C18(85%)) complexes relative to the DMPC ((C14)2) or POPC (C16, C18:1) complexes is attributed to the stronger van der Waals attraction between the HSPC acyl tails, relative to the shorter or un-saturated tails of the other two lipids. Our results shed light on possible lubrication mechanisms at the articular cartilage surface in joints. STATEMENT OF SIGNIFICANCE Can designed biomaterials emulate the unique lubrication ability of articular cartilage, and thus provide potential alleviation to friction-related joint diseases? This is the motivation behind the present study. The principles of cartilage lubrication have attracted considerable attention for decades, and several models have been proposed to elucidate it, however, the mechanism of this ultralow friction is still not clear. In this paper we explore the recent suggestion that its efficient lubrication arises from boundary layers of hyaluronan-lipid complexes at its surface, in particular exploring a range of different phosphatidylcholines (PCs) mimicking the wide range of PCs in synovial joints. The present study suggests a synergistic lubricating behavior of the different lipids in living joints, and potential treatment directions using such biomaterial complexes for widespread cartilage-friction-related diseases such as osteoarthritis.
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Sorkin R, Kampf N, Klein J. Effect of Cholesterol on the Stability and Lubrication Efficiency of Phosphatidylcholine Surface Layers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:7459-7467. [PMID: 28666386 DOI: 10.1021/acs.langmuir.7b01521] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The lubrication properties of saturated PC lipid vesicles containing high cholesterol content under high loads were examined by detailed surface force balance measurements of normal and shear forces between two surface-attached lipid layers. Forces between two opposing mica surfaces bearing distearoylphosphatidylcholine (PC) (DSPC) small unilamellar vesicles (SUVs, or liposomes), or bilayers, with varying cholesterol content were measured across water, whereas dimyristoyl PC (DMPC), dipalmitoyl PC (DPPC), and DSPC SUVs containing 40% cholesterol were measured across liposome dispersions of SUVs of the same lipid composition as in the adsorbed layers. The results clearly demonstrate decreased stability and resistance to normal load with the increase in cholesterol content of DSPC SUVs. Friction coefficients between two 10% cholesterol PC-bilayers were in the same range as for 40% cholesterol bilayers (μ ≈ 10-3), indicating that cholesterol has a more substantial effect on the mechanical properties of a bilayer than on its lubrication performance. We further find that the lubrication efficiency of DMPC and DPPC with 40% cholesterol is superior to that of DSPC 40% cholesterol, most likely because of enhanced hydration-lubrication in these systems. We previously found that when experiments are performed in the presence of a lipid reservoir, layers can self-heal and therefore their robustness is less important under such conditions. We conclude that the effect of cholesterol in decreasing the stability is more pronounced than its effect on hydration, but the stability is, in turn, less important when a lipid reservoir is present. This study complements our previous work and sheds light on the effect of cholesterol, a prominent and important physiological lipid, on the mechanical and lubrication properties of gel-phase lipid layers.
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Affiliation(s)
- Raya Sorkin
- Materials and Interfaces Department, Weizmann Institute of Science , Rehovot 76100, Israel
| | - Nir Kampf
- Materials and Interfaces Department, Weizmann Institute of Science , Rehovot 76100, Israel
| | - Jacob Klein
- Materials and Interfaces Department, Weizmann Institute of Science , Rehovot 76100, Israel
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Raj A, Wang M, Liu C, Ali L, Karlsson NG, Claesson PM, Dėdinaitė A. Molecular synergy in biolubrication: The role of cartilage oligomeric matrix protein (COMP) in surface-structuring of lubricin. J Colloid Interface Sci 2017; 495:200-206. [DOI: 10.1016/j.jcis.2017.02.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 02/03/2017] [Accepted: 02/06/2017] [Indexed: 11/28/2022]
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Li J, Luo J. Nonlinear Frictional Energy Dissipation between Silica-Adsorbed Surfactant Micelles. J Phys Chem Lett 2017; 8:2258-2262. [PMID: 28468497 DOI: 10.1021/acs.jpclett.7b00744] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The origin of energy dissipation underlies all friction processes, which is crucial in the design of extremely low friction and wear systems. Amontons's friction law shows that the frictional energy dissipation should be linear with load because of the constant friction coefficient. However, in this Letter, we present the nonlinear behavior of frictional energy dissipation in boundary lubrication with silica-adsorbed surfactant micelles. There exist two completely different friction regimes: a near-zero friction regime with very little energy dissipation and a nonlinear friction regime with a great deal of extra energy dissipation. The additional energy dissipation presents a square (nonlinear) relation with applied load, originating from the elastic deformation of the adsorbed micelle layer on the two friction surfaces, which is tightly linked to the stiffness of the micelle layer and the diameter of the contact area.
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Affiliation(s)
- Jinjin Li
- State Key Laboratory of Tribology, Tsinghua University , Beijing 100084, China
| | - Jianbin Luo
- State Key Laboratory of Tribology, Tsinghua University , Beijing 100084, China
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Lin W, Nietzel S, Klapper M, Müllen K, Klein J. Normal and shear forces between surfaces bearing phosphocholinated polystyrene nanoparticles. POLYM ADVAN TECHNOL 2017. [DOI: 10.1002/pat.3859] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Weifeng Lin
- Department of Materials and Interfaces; Weizmann Institute of Science; Rehovot 76100 Israel
| | - Sven Nietzel
- Max Planck Institute for Polymer Research; Ackermannweg 10 D-55128 Mainz Germany
| | - Markus Klapper
- Max Planck Institute for Polymer Research; Ackermannweg 10 D-55128 Mainz Germany
| | - Klaus Müllen
- Max Planck Institute for Polymer Research; Ackermannweg 10 D-55128 Mainz Germany
| | - Jacob Klein
- Department of Materials and Interfaces; Weizmann Institute of Science; Rehovot 76100 Israel
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48
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Briscoe WH. Aqueous boundary lubrication: Molecular mechanisms, design strategy, and terra incognita. Curr Opin Colloid Interface Sci 2017. [DOI: 10.1016/j.cocis.2016.09.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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49
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Kampf N, Wu C, Wang Y, Klein J. A Trimeric Surfactant: Surface Micelles, Hydration-Lubrication, and Formation of a Stable, Charged Hydrophobic Monolayer. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:11754-11762. [PMID: 27760462 DOI: 10.1021/acs.langmuir.6b02657] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The surface structure of the trimeric surfactant tri(dodecyldimethylammonioacetoxy)diethyltriamine trichloride (DTAD) on mica and the interactions between two such DTAD-coated surfaces were determined using atomic force microscopy and a surface force balance. In an aqueous solution of 3 mM, 5 times the critical aggregation concentration (CAC), the surfaces are coated with wormlike micelles or hemimicelles and larger (∼80 nm) bilayer vesicles. Repulsive normal interactions between the surfaces indicate a net surface charge and a solution concentration of ions close to that expected from the CAC. Moreover, this surface coating is strongly lubricating up to some tens of atmospheres, attributed to the hydration-lubrication mechanism acting at the exposed, highly hydrated surfactant headgroups. Upon replacement of the DTAD solution with surfactant-free water, the surface structures have changed on the DTAD monolayers, which then jump into adhesive contact on approach, both in water and following addition of 0.1 M NaNO3. This trimeric surfactant monolayer, which is highly hydrophobic, is found to be positively charged, which is evident from the attraction between the DTAD monolayer and negatively charged bare mica across water. These monolayers are stable over days even under a salt solution. The stability is attributed to the several stabilization pathways available to DTAD on the mica surface.
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Affiliation(s)
- Nir Kampf
- Department of Materials and Interfaces, Weizmann Institute of Science , Rehovot 76100, Israel
| | - Chunxian Wu
- Key Laboratory of Colloid and Interface Science, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China
| | - Yilin Wang
- Key Laboratory of Colloid and Interface Science, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China
| | - Jacob Klein
- Department of Materials and Interfaces, Weizmann Institute of Science , Rehovot 76100, Israel
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50
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Duan Y, Liu Y, Zhang C, Chen Z, Wen S. Insight into the Tribological Behavior of Liposomes in Artificial Joints. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:10957-10966. [PMID: 27687876 DOI: 10.1021/acs.langmuir.6b02822] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Liposomes are widely used in drug delivery and gene therapy, and their new role as boundary lubricant in natural/artificial joints has been found in recent years. In this study, the tribological properties of liposomes on titanium alloy (Ti6Al4 V)/UHMWPE interface were studied by a ball-on-disc tribometer. The efficient reduction of friction coefficient and wear on both surfaces under various velocities and loads is found. A multilayer structure of physically adsorbed liposomes on Ti6Al4 V surface was also observed by atomic force microscope (AFM). Except for the hydration mechanism by phosphatidylcholine (PC) groups, the well-performed tribological properties by liposomes is also attributed to the existence of adsorbed liposome layers on both surfaces, which could reduce asperities contact and show great bearing capacity. This work enriches the research on liposomes for lubrication improvement on artificial surface and shows their value in clinical application.
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Affiliation(s)
- Yiqin Duan
- State Key Laboratory of Tribology, Tsinghua University , Beijing 100084, China
| | - Yuhong Liu
- State Key Laboratory of Tribology, Tsinghua University , Beijing 100084, China
| | - Caixia Zhang
- Beijing Key Laboratory of Advanced Manufacturing Technology, Beijing University of Technology , Beijing 100124, China
| | - Zhe Chen
- State Key Laboratory of Tribology, Tsinghua University , Beijing 100084, China
| | - Shizhu Wen
- State Key Laboratory of Tribology, Tsinghua University , Beijing 100084, China
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